PARTICIPATION OF THE CENTRAL NORADRENERGIC SYSTEM IN THE REESTABLISHMENT OF COPULATORY-BEHAVIOR OF SEXUALLY EXHAUSTED RATS BY YOHIMBINE, NALOXONE, AND 8-OH-DPAT
G. Rodriguezmanzo et A. Fernandezguasti, PARTICIPATION OF THE CENTRAL NORADRENERGIC SYSTEM IN THE REESTABLISHMENT OF COPULATORY-BEHAVIOR OF SEXUALLY EXHAUSTED RATS BY YOHIMBINE, NALOXONE, AND 8-OH-DPAT, Brain research bulletin, 38(4), 1995, pp. 399-404
This study analyzes the impact of a neurotoxic lesion of the central n
oradrenergic system on the pharmacological reversal of the sexual inhi
bition present at sexual exhaustion, by IP treatment with yohimbine (2
mg/kg), 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) (0.25 mg/k
g), and naloxone (3 mg/kg), All drugs, at the doses tested, were able
to increase the percentage of sexually exhausted intact rats showing c
opulatory behavior 24 h after a sexual satiation session. In N-(a-chlo
roethyl)-N-ethyl-2-2-bromobenzylamine (DSP4)-lesioned, sexually exhaus
ted animals, naloxone and 8-OH-DPAT lost their stimulatory effect on s
exual behavior; yohimbine treatment was still able to markedly increas
e the percentage of satiated rats mounting, intromitting, and exhibiti
ng the ejaculatory motor pattern, but inhibited seminal emission, The
data strongly suggest that the integrity of the central noradrenergic
system is essential for the pharmacological reestablishment of copulat
ory behavior in sexually exhausted rats, Results are in line with prev
ious data showing that the sexual behavioral variables more directly a
ddressing motivational components are severly affected by sexual satia
tion.