A possible role for angiotensin II in the regulation of male sexual behavior in rats.
To investigate the possibility that angiotensin II (AII) is involved in the regulation of male sexual behavior, AII was injected intraventricularly into sexually experienced male rats immediately prior to mating tests. Third ventricular administration of 0.48 nmol AII resulted in an increased latency to the initiation of copulatory behavior (625% of control values), and administration of 4.8 nmol had a similar effect on initiation latencies (650% of control values) and, additionally, significantly increased the number of intromissions preceding ejaculation (the ejaculatory threshold, to 130% of control values) and the interval to reinitiate copulatory behavior after ejaculation (the postejaculatory interval, to 125% of control values). Water intake was affected only by the higher dose of AII, with no animals drinking in the 15 minutes following saline or 0.48 nmol AII and 69% of the rats treated with 4.8 nmol AII drinking (mean intake 1.5 +/- 0.26 ml for those rats drinking). These data demonstrate that AII can suppress male sexual behavior, and that this suppression is not due simply to a stimulation of drinking.
Clark
J T
JT
Department of Physiology, Meharry Medical College, Nashville, TN 37208.
D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D001143:Arousal / Q000502:physiology; D001921:Brain / Q000502:physiology; D003307:Copulation / Q000502:physiology; D004326:Drinking; D004542:Ejaculation; D008297:Male; D051381:Rats; D011930:Reaction Time / Q000502:physiology; D011945:Receptors, Angiotensin / Q000502:physiology; D012726:Sexual Behavior, Animal / Q000502:physiology*
D011945:Receptors, Angiotensin; D000804:Angiotensin II