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  • Deletion of the testosterone-sensitive TRPM8 Ca++ channel disrupts measures of anxiety and depression in mice: Implications for dopamine
Title: Deletion of the testosterone-sensitive TRPM8 Ca++ channel disrupts measures of anxiety and depression in mice: Implications for dopamine
Testosterone exerts high affinity for the Transient Receptor Potential Melastatin 8 (TRPM8) Ca2+ channel. TRPM8 -/- male mice exhibit disrupted sexual behavior (e.g., indiscriminate approach, delayed satiety), possibly due to decreased ventral tegmental area dopamine neuron activity. It is hypothesized that TRPM8 null mutant mice (Jackson Laboratories) will exhibit disruptions across a range of motivationally-relevant behaviors, including spontaneous locomotor activation, detection of novel stimuli, sucrose preference, and sensitivity to the psychomotor stimulant amphetamine. Initial findings indicate that male TRPM8 mutant mice (n=6) exhibit decreased nocturnal locomotor activity (F(1,12)=23.41, p<0.001), increased behavioral anxiety in the light/dark task (t(10)=2.44, p<0.05; d=1.4), and behavioral despair in the forced swim task (t(10)=3.70, p<0.005; d=2.1). In contrast, these mice tended to prefer a low concentration (0.1%) of sucrose compared to wildtype males (n=6; t(10)=1.35, p=0.09; d=0.83). Tests for sensitivity to amphetamine are in progress. These data suggest a pivotal role for TRPM8 in motivated behavior.  more » « less
Award ID(s):
1922428
PAR ID:
10563725
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Bradley University
Date Published:
Format(s):
Medium: X
Location:
Bradley University, Peoria, Illinois
Sponsoring Org:
National Science Foundation
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