Inhibitory effects of the 5-HT1A agonists, 5-hydroxy- and 5-methoxy-(3-di-n-propylamino)chroman, on female lordosis behavior.
Sexually receptive, intact, proestrous rats were infused bilaterally into the ventromedial nucleus of the hypothalamus with one of several serotonin (5-HT) agonists and with the endogenous ligand, 5-HT. Serotonin (2000 ng) and the 5-HT1A agonists, 8-hydroxy-2-(di-n-propylamino)tetralin [8-OH-DPAT (200 ng)], 5-methoxy-3-(di-n-propylamino)chroman [5-MEO-DPAC (200-2000 ng)] and 5-hydroxy-3-(N-di-n-propylamino)chroman [5-OH-DPAC (200-2000 ng)] inhibited female lordosis behavior within 10 min of the infusion. The rank order of the effectiveness of these compounds was 8-OH-DPAT > 5-OH-DPAC > or = 5-MEO-DPAC > 5-HT. The nonselective 5-HT agonist, 1-(m-trifluoromethyl) piperazine [TFMPP (2000 ng)], did not reduce lordosis behavior. In addition to their reduction of lordosis behavior, the 5-HT1A agonists elicited resistive behavior toward the male's attempts to mount. There were minimal effects of the 5-HT1A agonists on either quality of the lordosis reflex or on proceptivity. However, rats pretreated with TFMPP and infused with 8-OH-DPAT 1 hr later, did show a transient suppression of lordosis quality. These results provide further evidence that the ventromedial nucleus of the hypothalamus contains 5-HT1A sites, the activation of which reduces lordosis behavior in regularly cycling, proestrous rats.
Uphouse
L
L
Department of Biology, Texas Women's University, Denton 76204.
Caldarola-Pastuszka
M
M
Moore
N
N
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D002839:Chromans / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D007267:Injections; D008297:Male; D010879:Piperazines / Q000494:pharmacology; D011187:Posture; D011359:Proestrus / Q000502:physiology; D051381:Rats; D011916:Rats, Inbred F344; D012701:Serotonin / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D014697:Ventromedial Hypothalamic Nucleus / Q000033:anatomy & histology
D002839:Chromans; D010879:Piperazines; D017366:Serotonin Receptor Agonists; C071048:3-propylamino-5-hydroxychroman; C054083:5-methoxy-3-(di-n-propylamino)chroman; C018406:1-(3-trifluoromethylphenyl)piperazine; D012701:Serotonin; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin