Gepirone and 1-(2-pyrimidinyl)-piperazine-induced reduction of aversively evoked ultrasonic vocalisation in the rat.
Ultrasonic (22 kHz) vocalisation in response to a mildly aversive foot shock was measured in the dark compartment of a light-dark box both immediately and 24 h after the shock. Gepirone (1 and 5 mg/kg, IP) produced a reduction in the duration of vocalisation at both times. Although a metabolic inhibitor, proadifen (40 mg/kg) did not reduce this effect of gepirone, the gepirone hepatic metabolite, 1-(2-pyrimidinyl)-piperazine (1-PP, 1 mg/kg), was also active in the test. Performance of a 24 h step-through passive avoidance task was impaired by gepirone only at a dose, 5 mg/kg, which also reduced spontaneous locomotor and rearing activity in the apparatus. It would appear that mild foot shock-evoked ultrasonic vocalisation may provide a more sensitive indicator of the effect of gepirone and related drugs on the affective response of rats to aversive stimulation.
Cullen
W K
WK
Department of Pharmacology and Therapeutics, Trinity College, Dublin, Ireland.
Rowan
M J
MJ
D000818:Animals; D014151:Anti-Anxiety Agents / Q000493:pharmacokinetics / Q000494:pharmacology*; D001362:Avoidance Learning / Q000187:drug effects; D002065:Buspirone / Q000031:analogs & derivatives* / Q000494:pharmacology; D003624:Darkness; D004597:Electroshock; D008027:Light; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D011335:Proadifen / Q000494:pharmacology; D011743:Pyrimidines / Q000493:pharmacokinetics / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014465:Ultrasonics; D014828:Vocalization, Animal / Q000187:drug effects*
D014151:Anti-Anxiety Agents; D011743:Pyrimidines; D011335:Proadifen; C037921:1-(2-pyrimidinyl)piperazine; C039979:gepirone; D002065:Buspirone