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• 21. [Article] How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage

  The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden ...

  Citation × Citation Citation Abstract Copy Title: How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage Author: Brunkalla, Roberta Year: 2016 The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden changes in weather patterns can quickly impact lake thermal structure, which can rapidly influence the competition between buoyancy regulating cyanobacteria. By modeling competition, I hope to address how altered climate would shift the competitive advantage to toxin forming cyanobacteria. I plan on accomplishing this by coupling a one-dimensional hydrodynamic and algal competition model, with lake specific physiological parameters. A sensitivity test of the model could reveal dramatic shifts in algal competition under future climate change scenarios, which could have implications in how Upper Klamath Lake is managed and how restoration efforts are implemented. Title: How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage Author: Brunkalla, Roberta Year: 2016 The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden changes in weather patterns can quickly impact lake thermal structure, which can rapidly influence the competition between buoyancy regulating cyanobacteria. By modeling competition, I hope to address how altered climate would shift the competitive advantage to toxin forming cyanobacteria. I plan on accomplishing this by coupling a one-dimensional hydrodynamic and algal competition model, with lake specific physiological parameters. A sensitivity test of the model could reveal dramatic shifts in algal competition under future climate change scenarios, which could have implications in how Upper Klamath Lake is managed and how restoration efforts are implemented. Close

• 22. [Article] Effects of dehydration on hemoglobin oxygen affinity and blood cell volume in two anurans

  Two aspects of possible adaptation In cardiovascular performance caused by Increased plasma electrolytes were examined. Cells In anisotonic plasma may either act as osmometers or volume regulate. Blood ...

  Citation × Citation Citation Abstract Copy Title: Effects of dehydration on hemoglobin oxygen affinity and blood cell volume in two anurans Author: Zygmunt, Andrew Christopher Year: 1984 Two aspects of possible adaptation In cardiovascular performance caused by Increased plasma electrolytes were examined. Cells In anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate Is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which Increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell Is maintain constant volume during dehydration. Cells in vitro Initially lose water, but then sodium, potassium and water move Into the cell. Cell viscosity within the physiologic range of hematocrits was higher In salt loaded non-regulating cell Is of B. marinus than In regulating isotonic cells. Title: Effects of dehydration on hemoglobin oxygen affinity and blood cell volume in two anurans Author: Zygmunt, Andrew Christopher Year: 1984 Two aspects of possible adaptation In cardiovascular performance caused by Increased plasma electrolytes were examined. Cells In anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate Is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which Increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell Is maintain constant volume during dehydration. Cells in vitro Initially lose water, but then sodium, potassium and water move Into the cell. Cell viscosity within the physiologic range of hematocrits was higher In salt loaded non-regulating cell Is of B. marinus than In regulating isotonic cells. Close

• 23. [Article] Antioxidant Anthocyanidins and Calcium Transport Modulation of the Ryanodine Receptor of Skeletal Muscle (RyR1)

  Cardiovascular disease (CVD) claims more lives than any other disease in the world. Although numerous biological pathways share the blame, ventricular tachyarrhythmia (VT) is estimated to account for ~25% ...

  Citation × Citation Citation Abstract Copy Title: Antioxidant Anthocyanidins and Calcium Transport Modulation of the Ryanodine Receptor of Skeletal Muscle (RyR1) Author: Dornan, Thomas J. Year: 2011 Cardiovascular disease (CVD) claims more lives than any other disease in the world. Although numerous biological pathways share the blame, ventricular tachyarrhythmia (VT) is estimated to account for ~25% of all CVD deaths. A complete understanding of the molecular mechanisms underlying VT is unknown but recent studies have linked VT to improper calcium handling in the heart (canine). The principle calcium regulator in the muscle cell is the calcium ion release channel (aka RyR). Numerous endogenous and exogenous compounds can affect the way the RyR regulates calcium. In particular, abnormal levels of oxidants (reactive oxygen species) can oxidize critical thiol groups on the RyR and modulate its activity. Interestingly, high levels of oxidants are also associated with numerous bodily disease states including cancers, muscle fatigue/failure, and CVD. In this thesis, two important dietary antioxidant compounds, the anthocyanidins pelargonidin and delphinidin, are evaluated for their effects on regulating the transport of calcium through the calcium release channel (RyR1) of the sarcoplasmic reticulum of skeletal muscle. Pelargonidin and delphinidin are structurally similar with delphinidin only differing from pelargonidin by the addition of two hydroxyl groups. Both compounds undergo time dependent structural changes in aqueous solutions at physiological pH and a mixture of more than four structures of each compound can be present in solution simultaneously. Pelargonidin and delphinidin show distinct differences in their calcium flux regulating effect on the RyR1. Delphinidin stimulates calcium flux and RyR1 activity where as pelargonidin can cause both inhibition and stimulation of the RyR1. The strength of stimulation and inhibition of calcium transport through the RyR by delphinidin and pelargonidin may be attributed to the structural and chemical changes in those compounds that occur in solutions near physiological pH and the subsequent chemical characteristics of the diverse set of structures that are simultaneously present in solution. Title: Antioxidant Anthocyanidins and Calcium Transport Modulation of the Ryanodine Receptor of Skeletal Muscle (RyR1) Author: Dornan, Thomas J. Year: 2011 Cardiovascular disease (CVD) claims more lives than any other disease in the world. Although numerous biological pathways share the blame, ventricular tachyarrhythmia (VT) is estimated to account for ~25% of all CVD deaths. A complete understanding of the molecular mechanisms underlying VT is unknown but recent studies have linked VT to improper calcium handling in the heart (canine). The principle calcium regulator in the muscle cell is the calcium ion release channel (aka RyR). Numerous endogenous and exogenous compounds can affect the way the RyR regulates calcium. In particular, abnormal levels of oxidants (reactive oxygen species) can oxidize critical thiol groups on the RyR and modulate its activity. Interestingly, high levels of oxidants are also associated with numerous bodily disease states including cancers, muscle fatigue/failure, and CVD. In this thesis, two important dietary antioxidant compounds, the anthocyanidins pelargonidin and delphinidin, are evaluated for their effects on regulating the transport of calcium through the calcium release channel (RyR1) of the sarcoplasmic reticulum of skeletal muscle. Pelargonidin and delphinidin are structurally similar with delphinidin only differing from pelargonidin by the addition of two hydroxyl groups. Both compounds undergo time dependent structural changes in aqueous solutions at physiological pH and a mixture of more than four structures of each compound can be present in solution simultaneously. Pelargonidin and delphinidin show distinct differences in their calcium flux regulating effect on the RyR1. Delphinidin stimulates calcium flux and RyR1 activity where as pelargonidin can cause both inhibition and stimulation of the RyR1. The strength of stimulation and inhibition of calcium transport through the RyR by delphinidin and pelargonidin may be attributed to the structural and chemical changes in those compounds that occur in solutions near physiological pH and the subsequent chemical characteristics of the diverse set of structures that are simultaneously present in solution. Close

• 24. [Article] Investigating the Origin and Functions of a Novel Small RNA in <i>Escherichia coli</i>

  Non-coding small RNAs (sRNAs) regulate various cellular processes in bacteria. They bind to a chaperone protein Hfq for stability and regulate gene expression by base-pairing with target mRNAs. Although ...

  Citation × Citation Citation Abstract Copy Title: Investigating the Origin and Functions of a Novel Small RNA in <i>Escherichia coli</i> Author: Kacharia, Fenil Rashmin Year: 2016 Non-coding small RNAs (sRNAs) regulate various cellular processes in bacteria. They bind to a chaperone protein Hfq for stability and regulate gene expression by base-pairing with target mRNAs. Although the importance of sRNAs in bacteria has been well established, the mode of origination of novel sRNA genes is still elusive, mainly because the rapid rate of evolution of sRNAs obscures their original sources. To overcome this impediment, we identified a recently formed sRNA (EcsR2) in E. coli, and show that it evolved from a degraded bacteriophage gene. Our analyses also revealed that young sRNAs such as EcsR2 are expressed at low levels and evolve at a rapid rate in comparison to older sRNAs, thereby uncovering a novel process that potentially facilitates newly emerging (and probably mildly deleterious) sRNAs to persist in bacterial genomes. We also show that even though EcsR2 is slightly deleterious to E. coli, it could bind to Hfq and mRNAs to regulate the expression of several genes. Interestingly, while EcsR2 expression is induced by glucose, the expression of its putative targets are regulated by the transcription factor CRP in response to glucose, indicating that EcsR2 has been incorporated into the carbon regulatory network in E. coli. Collectively, this work provides evidence for the emergence, evolution and functions of a novel "young" sRNA in bacteria. Title: Investigating the Origin and Functions of a Novel Small RNA in <i>Escherichia coli</i> Author: Kacharia, Fenil Rashmin Year: 2016 Non-coding small RNAs (sRNAs) regulate various cellular processes in bacteria. They bind to a chaperone protein Hfq for stability and regulate gene expression by base-pairing with target mRNAs. Although the importance of sRNAs in bacteria has been well established, the mode of origination of novel sRNA genes is still elusive, mainly because the rapid rate of evolution of sRNAs obscures their original sources. To overcome this impediment, we identified a recently formed sRNA (EcsR2) in E. coli, and show that it evolved from a degraded bacteriophage gene. Our analyses also revealed that young sRNAs such as EcsR2 are expressed at low levels and evolve at a rapid rate in comparison to older sRNAs, thereby uncovering a novel process that potentially facilitates newly emerging (and probably mildly deleterious) sRNAs to persist in bacterial genomes. We also show that even though EcsR2 is slightly deleterious to E. coli, it could bind to Hfq and mRNAs to regulate the expression of several genes. Interestingly, while EcsR2 expression is induced by glucose, the expression of its putative targets are regulated by the transcription factor CRP in response to glucose, indicating that EcsR2 has been incorporated into the carbon regulatory network in E. coli. Collectively, this work provides evidence for the emergence, evolution and functions of a novel "young" sRNA in bacteria. Close

• 25. [Article] "So Far from Home ..." : a Translation of Jacques Sternberg's "Si loin du monde ..."

  This master's thesis comprises an English translation of Jacques Sternberg's "Si loin du monde ..." preceded by an introduction that addresses the translator's general theoretical approach to translation ...

  Citation × Citation Citation Abstract Copy Title: "So Far from Home ..." : a Translation of Jacques Sternberg's "Si loin du monde ..." Author: Mather, Brian Scott Year: 2016 This master's thesis comprises an English translation of Jacques Sternberg's "Si loin du monde ..." preceded by an introduction that addresses the translator's general theoretical approach to translation as well as an explanation and justification of specific choices made for this translation in particular. "Si loin du monde ..." is a short work of science fiction by Belgian author Jacques Sternberg that appeared in the collection Entre deux mondes incertains, published in 1957. It takes the form of a first-person narrative told from the perspective of an extra-terrestrial, who has been sent on a mission to study humanity and its environment and furtively make preparation for the arrival of his people on Earth. The section on theory sets out to find whether there exist absolute norms exterior to the subjectivity of the translator that regulate the act of translation. Three potential normative centers are proposed: text, author, and reader. The starting point when appraising text is the sourcier/cibliste dichotomy and the objection préjudicielle presented in Georges Mounin's Les belles infidèles. The objection préjudicielle is the claim that translation is theoretically impossible. The conclusion reached is that the text does not establish absolute norms of correspondence between the target text and the source text because there is no absolute meaning inherent in the text. When examining the author as a potential source of the norms of translation, Roland Barthe"s "La mort de l'auteur" is used to show that, since the meaning of a text is not ultimately determined by the author, neither can he be an absolute regulator of correspondence in translation. Finally, the reader is found to be a relative (not absolute) regulator of the norms of translation. This regulating role and the nature of its demands on the translator is explored through an application of the author/reader dialectic found in Sartre's Qu'est-ce que la littérature? It is concluded that there do not exist any absolute norms of translation exterior to the translator, and that the translator creates an aesthetic unity in the target text through adherence to norms that are ultimately founded in his own subjectivity. Title: "So Far from Home ..." : a Translation of Jacques Sternberg's "Si loin du monde ..." Author: Mather, Brian Scott Year: 2016 This master's thesis comprises an English translation of Jacques Sternberg's "Si loin du monde ..." preceded by an introduction that addresses the translator's general theoretical approach to translation as well as an explanation and justification of specific choices made for this translation in particular. "Si loin du monde ..." is a short work of science fiction by Belgian author Jacques Sternberg that appeared in the collection Entre deux mondes incertains, published in 1957. It takes the form of a first-person narrative told from the perspective of an extra-terrestrial, who has been sent on a mission to study humanity and its environment and furtively make preparation for the arrival of his people on Earth. The section on theory sets out to find whether there exist absolute norms exterior to the subjectivity of the translator that regulate the act of translation. Three potential normative centers are proposed: text, author, and reader. The starting point when appraising text is the sourcier/cibliste dichotomy and the objection préjudicielle presented in Georges Mounin's Les belles infidèles. The objection préjudicielle is the claim that translation is theoretically impossible. The conclusion reached is that the text does not establish absolute norms of correspondence between the target text and the source text because there is no absolute meaning inherent in the text. When examining the author as a potential source of the norms of translation, Roland Barthe"s "La mort de l'auteur" is used to show that, since the meaning of a text is not ultimately determined by the author, neither can he be an absolute regulator of correspondence in translation. Finally, the reader is found to be a relative (not absolute) regulator of the norms of translation. This regulating role and the nature of its demands on the translator is explored through an application of the author/reader dialectic found in Sartre's Qu'est-ce que la littérature? It is concluded that there do not exist any absolute norms of translation exterior to the translator, and that the translator creates an aesthetic unity in the target text through adherence to norms that are ultimately founded in his own subjectivity. Close

• 26. [Article] Behavioral Temperature Regulation in the Turtle Pseudemys Scripta Elegans

  A group of red-eared turtles (Pseudemys scripta elegans) was acclimated to 18-20˚C and artificial photo-period for 21 days. The animals were then individually placed in a thermal gradient and their selected ...

  Citation × Citation Citation Abstract Copy Title: Behavioral Temperature Regulation in the Turtle Pseudemys Scripta Elegans Author: Johnston, Michael H. Year: 1977 A group of red-eared turtles (Pseudemys scripta elegans) was acclimated to 18-20˚C and artificial photo-period for 21 days. The animals were then individually placed in a thermal gradient and their selected temperatures were continuously recorded for 24 hours. A second group of turtles was acclimatized to 7.5-11.0˚C and natural photoperiods for 28 days, and subsequently tested in the same manner as the first group. Lastly, the turtles in the first group, after being acclimated to 3.0˚C and the previous artificial photoperiod for 14 days, were retested in the gradient. Title: Behavioral Temperature Regulation in the Turtle Pseudemys Scripta Elegans Author: Johnston, Michael H. Year: 1977 A group of red-eared turtles (Pseudemys scripta elegans) was acclimated to 18-20˚C and artificial photo-period for 21 days. The animals were then individually placed in a thermal gradient and their selected temperatures were continuously recorded for 24 hours. A second group of turtles was acclimatized to 7.5-11.0˚C and natural photoperiods for 28 days, and subsequently tested in the same manner as the first group. Lastly, the turtles in the first group, after being acclimated to 3.0˚C and the previous artificial photoperiod for 14 days, were retested in the gradient. Close

• 27. [Article] The Body: Conceptualizing Abortion in Contemporary Ireland

  Currently abortion is illegal in Ireland. This thesis uses personal and political discussions about abortion I had during a study abroad in Ireland to engage larger concepts of the institutional (Church ...

  Citation × Citation Citation Abstract Copy Title: The Body: Conceptualizing Abortion in Contemporary Ireland Author: Ellis-Curry, Sofia Year: 2015 Currently abortion is illegal in Ireland. This thesis uses personal and political discussions about abortion I had during a study abroad in Ireland to engage larger concepts of the institutional (Church and State) and the symbolic (justice and morality). This work seeks to highlight how the Catholic Church and the nation-state benefit from the regulation of women's bodies. Through the continued regulation of women's bodies, specifically around access to abortion, the nation-state can better control projects of race, class, gender, sexuality and ability in order maintain strict notions of citizenship and preserve Irish identity reclamation projects. Title: The Body: Conceptualizing Abortion in Contemporary Ireland Author: Ellis-Curry, Sofia Year: 2015 Currently abortion is illegal in Ireland. This thesis uses personal and political discussions about abortion I had during a study abroad in Ireland to engage larger concepts of the institutional (Church and State) and the symbolic (justice and morality). This work seeks to highlight how the Catholic Church and the nation-state benefit from the regulation of women's bodies. Through the continued regulation of women's bodies, specifically around access to abortion, the nation-state can better control projects of race, class, gender, sexuality and ability in order maintain strict notions of citizenship and preserve Irish identity reclamation projects. Close

• 28. [Article] "Mind-Blowing": Fostering Self-Regulated Learning in Information Literacy Instruction

  The new ACRL Framework for Information Literacy for Higher Education brings a new emphasis into our instruction on student metacognition and dispositions. In this article I introduce self-regulated learning, ...

  Citation × Citation Citation Abstract Copy Title: "Mind-Blowing": Fostering Self-Regulated Learning in Information Literacy Instruction Author: Houtman, Eveline Year: 2015 The new ACRL Framework for Information Literacy for Higher Education brings a new emphasis into our instruction on student metacognition and dispositions. In this article I introduce self-regulated learning, a related concept from the field of education; it encompasses metacognition, emotions, motivations and behaviors. I discuss how this concept could be important and helpful in implementing the related elements in the ACRL Framework and draw on the concept to devise strategies and activities that promote students' self-awareness and learning skills. This focus promotes a more learner-centered approach to teaching. The article also adds to the conversation on developing a self-reflective pedagogical praxis in information literacy instruction. Title: "Mind-Blowing": Fostering Self-Regulated Learning in Information Literacy Instruction Author: Houtman, Eveline Year: 2015 The new ACRL Framework for Information Literacy for Higher Education brings a new emphasis into our instruction on student metacognition and dispositions. In this article I introduce self-regulated learning, a related concept from the field of education; it encompasses metacognition, emotions, motivations and behaviors. I discuss how this concept could be important and helpful in implementing the related elements in the ACRL Framework and draw on the concept to devise strategies and activities that promote students' self-awareness and learning skills. This focus promotes a more learner-centered approach to teaching. The article also adds to the conversation on developing a self-reflective pedagogical praxis in information literacy instruction. Close

• 29. [Article] Neurobiology of Seasonal Life-history Transitions

  Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such ...

  Citation × Citation Citation Abstract Copy Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Close

• 30. [Article] Thermoregulation in Mice under the Influence of Ethanol

  Thermoregulation after acute ethanol, during chronic exposure and during withdrawal from ethanol dependency was studied using genetically heterogeneous (HS) mice, and lines of mice selected in replicate ...

  Citation × Citation Citation Abstract Copy Title: Thermoregulation in Mice under the Influence of Ethanol Author: O'Connor, Candace Sharon Year: 1993 Thermoregulation after acute ethanol, during chronic exposure and during withdrawal from ethanol dependency was studied using genetically heterogeneous (HS) mice, and lines of mice selected in replicate for smaller (HOT1, HOT2) or greater (COLD1, COLD2) decline in rectal temperature (Tre ) after intraperitoneal ethanol. First, HS mice were injected with 20% ethanol in 0.9% NaCI, or NaCI alone during sessions of behavioral thermoregulation in individual temperature gradients (9-38°C). Internal temperature (Tj ) was monitored with implanted telemetry devices. An imaging system recorded selected temperature (Tsel ) within the gradient every 5 sec. Acute 2.25 and 2.60 g ethanol/kg produced significantly lower Tj than NaCI. 2.60 g/kg also produced significantly lower Tsel than 2.25 g/kg or NaCI. 2.75 g/kg and above incapacitated mice. Comparison of responses using a thermoregulatory index indicated 2.25 or 2.60 g/kg decreased the regulated temperature. Similar methodology was followed using the selected lines and 10% ethanol (2.0, 2.25, 2.65 g/kg to COLD mice; 2.65, 2.85 g/kg to HOT mice; 3.0 g/kg to HOT2 mice) or NaCI. All responded similarly to NaCl, with transient rise in Tj After an effective ethanol dose mice manifested a regulated decrease in Tj by lowering Tsel concomitant with falling Tj . In both replicate pairs COLD mice were more sensitive than HOT, indicating that a true difference in the CNS regulator of body temperature was selected for in these animals. Photoperiod effect was characterized by quantifying thermoregulatory behavior of COLD2 mice after acute 2.60 g 7.5% ethanol/kg or NaCl, at 0400 , 0800 , 1200, 1600 , 2000 and 2400 hours , using above methodology. Baseline T₁ was significantly lower during hours of light, than during darkness. Photoperiod had little effect on thermoregulatory response to ethanol, possibly because of arousal associated with experiments. Thermoregulatory tolerance to ethanol was investigated using HS mice implanted with telemetry devices and monitored in the gradient on days 1, 2, 4, 7 and 11 of 11 consecutive days of 10% ethanol (2.75 g/kg) or NaCl injections. Dispositional, rapid and chronic tolerance developed, indicating that functional tolerance is a regulated phenomenon in mice. In a separate experiment HS mice were implanted with telemetry devices and injected with ethanol for 11 consecutive days at constant temperature; dispositional but not functional tolerance developed. To characterize thermoregulation during withdrawal, HS mice were made dependent upon ethanol using a vapor chamber; T; Tsel and activity were monitored in the gradient until 26 hours post withdrawal. Withdrawing mice showed unaltered regulated temperature, but lower Tsel than controls. This suggested increased metabolic heat production. Thermoregulation during withdrawal was similarly studied using the selected mouse lines. COLD mice responded like HS mice. Withdrawing HOT1 mice were more active than controls; withdrawing HOT2 mice showed lowest Tsel of any genotype but maintained Ti above controls. These results suggest a more severe withdrawal reaction in HOT, than in COLD mice. To investigate a possible mechanism underlying ethanol hypothermia, responses of HOT and COLD mice to intracerebroventricular serotonin were characterized. Dose-dependent decreases in Tre were measured in mice equipped with indwelling brain cannulae and held at constant temperature after injection of 0.3, 0.8, 2.0, 5.0 or 11.0 μg serotonin into the lateral brain ventricle. COLD mice were significantly more sensitive than HOT mice. Subsequently HOT1 and COLD1 mice were equipped with brain cannulae and implanted telemetry devices; thermoregulatory behavior after 11.0 μg serotonin was monitored. Both genotypes lowered Tj significantly more in the gradient than did similar mice at constant ambient temperature, indicating that decline in Tj after serotonin was a regulated phenomenon. The serotonergic system was altered during selection for differential Tre response to ethanol, indicating a role for serotonin in mediating ethanol hypothermia. Title: Thermoregulation in Mice under the Influence of Ethanol Author: O'Connor, Candace Sharon Year: 1993 Thermoregulation after acute ethanol, during chronic exposure and during withdrawal from ethanol dependency was studied using genetically heterogeneous (HS) mice, and lines of mice selected in replicate for smaller (HOT1, HOT2) or greater (COLD1, COLD2) decline in rectal temperature (Tre ) after intraperitoneal ethanol. First, HS mice were injected with 20% ethanol in 0.9% NaCI, or NaCI alone during sessions of behavioral thermoregulation in individual temperature gradients (9-38°C). Internal temperature (Tj ) was monitored with implanted telemetry devices. An imaging system recorded selected temperature (Tsel ) within the gradient every 5 sec. Acute 2.25 and 2.60 g ethanol/kg produced significantly lower Tj than NaCI. 2.60 g/kg also produced significantly lower Tsel than 2.25 g/kg or NaCI. 2.75 g/kg and above incapacitated mice. Comparison of responses using a thermoregulatory index indicated 2.25 or 2.60 g/kg decreased the regulated temperature. Similar methodology was followed using the selected lines and 10% ethanol (2.0, 2.25, 2.65 g/kg to COLD mice; 2.65, 2.85 g/kg to HOT mice; 3.0 g/kg to HOT2 mice) or NaCI. All responded similarly to NaCl, with transient rise in Tj After an effective ethanol dose mice manifested a regulated decrease in Tj by lowering Tsel concomitant with falling Tj . In both replicate pairs COLD mice were more sensitive than HOT, indicating that a true difference in the CNS regulator of body temperature was selected for in these animals. Photoperiod effect was characterized by quantifying thermoregulatory behavior of COLD2 mice after acute 2.60 g 7.5% ethanol/kg or NaCl, at 0400 , 0800 , 1200, 1600 , 2000 and 2400 hours , using above methodology. Baseline T₁ was significantly lower during hours of light, than during darkness. Photoperiod had little effect on thermoregulatory response to ethanol, possibly because of arousal associated with experiments. Thermoregulatory tolerance to ethanol was investigated using HS mice implanted with telemetry devices and monitored in the gradient on days 1, 2, 4, 7 and 11 of 11 consecutive days of 10% ethanol (2.75 g/kg) or NaCl injections. Dispositional, rapid and chronic tolerance developed, indicating that functional tolerance is a regulated phenomenon in mice. In a separate experiment HS mice were implanted with telemetry devices and injected with ethanol for 11 consecutive days at constant temperature; dispositional but not functional tolerance developed. To characterize thermoregulation during withdrawal, HS mice were made dependent upon ethanol using a vapor chamber; T; Tsel and activity were monitored in the gradient until 26 hours post withdrawal. Withdrawing mice showed unaltered regulated temperature, but lower Tsel than controls. This suggested increased metabolic heat production. Thermoregulation during withdrawal was similarly studied using the selected mouse lines. COLD mice responded like HS mice. Withdrawing HOT1 mice were more active than controls; withdrawing HOT2 mice showed lowest Tsel of any genotype but maintained Ti above controls. These results suggest a more severe withdrawal reaction in HOT, than in COLD mice. To investigate a possible mechanism underlying ethanol hypothermia, responses of HOT and COLD mice to intracerebroventricular serotonin were characterized. Dose-dependent decreases in Tre were measured in mice equipped with indwelling brain cannulae and held at constant temperature after injection of 0.3, 0.8, 2.0, 5.0 or 11.0 μg serotonin into the lateral brain ventricle. COLD mice were significantly more sensitive than HOT mice. Subsequently HOT1 and COLD1 mice were equipped with brain cannulae and implanted telemetry devices; thermoregulatory behavior after 11.0 μg serotonin was monitored. Both genotypes lowered Tj significantly more in the gradient than did similar mice at constant ambient temperature, indicating that decline in Tj after serotonin was a regulated phenomenon. The serotonergic system was altered during selection for differential Tre response to ethanol, indicating a role for serotonin in mediating ethanol hypothermia. Close