Intracerebroventricular LHRH may serve as a discriminative stimulus in male rats.
Male Wistar rats (N = 16) were trained to discriminate 5 micrograms/kg LHRH, injected intraperitoneally, from saline in a two-lever, food-reinforced drug discrimination procedure, with an injection-session interval of 45 min. Reliable discrimination of LHRH was acquired within 60 training sessions. Subsequent generalization tests in brain-cannulated animals showed dose-dependent and time-related partial substitution of intracerebroventricular LHRH for intraperitoneal LHRH (ventricle doses ranged from 25-400 ng, and the injection-session intervals ranged from 10-40 min). These results indicate that centrally administered LHRH may serve as a dose- and time-dependent discriminative stimulus in male rats.
de Beun
R
R
Netherlands Institute for Brian Research, Amsterdam.
Jansen
E
E
Heinsbroek
R P
RP
Slangen
J L
JL
van de Poll
N E
NE
D000818:Animals; D001921:Brain / Q000187:drug effects*; D003214:Conditioning, Classical / Q000187:drug effects*; D004193:Discrimination Learning / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005793:Generalization, Psychological / Q000187:drug effects; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D007987:Gonadotropin-Releasing Hormone