Timid Singly‐housed Mice: Their Value in Prediction of Psychotropic Activity of Drugs

Abstract

I About 45% of singly-housed male mice showed timidity (alert postures, running away, defensive postures) instead of aggression on interactions in pairs with group-housed male mice, though their partners did not show any aggression. The isolation-induced timidity was stable in repeated interactions. Timid mice also showed locomotion (walking across cage and rearing) and a small amount of sociable activity (sniffing, following partners and climbing over them). 2 Diazepam (5 mg/kg), chlordiazepoxide (20 mg/kg), chlorpromazine (7.5 mg/kg) and barbitone (60 mg/kg) given orally inhibited the isolation-induced timidity without reducing other motor activities in the timid mice. Imipramine lessened timidity only in a dose (80 mg/kg) which also decreased other components of behaviour in the timid isolates. (+)-Amphetamine and lysergic acid diethylamide (LSD) increased the timid response. 3 Comparison of the inhibition of timid activities with changes in other behaviour occurring at the same time seems a better measure of selective timidity-reducing effects of drugs than the rota-rod test. 4 Diazepam (5 mg/kg) increased sociable and locomotor activities. Barbitone (20 and 60 mg/kg) increased sociable activities; however, the higher dose also evoked some aggression in timid mice. 5 Behaviour of timid singly-housed male mice seems to be a good measure for prediction of activity of drugs in relieving anxiety as well sociability-increasing effects of drugs.as for detection of aggression-evoking and

Brain indoleamine 2,3-dioxygenase contributes to the comorbidity of pain and depression

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Stress-Induced Anhedonia in Mice is Associated with Deficits in Forced Swimming and Exploration

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Aggression Escalated by Social Instigation or by Discontinuation of Reinforcement (“Frustration”) in Mice Inhibition by Anpirtoline: A 5-HT1B Receptor Agonist

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