Oxytocin maintains as well as initiates female sexual behavior: effects of a highly selective oxytocin antagonist |
| |
Authors: | Pedersen Cort A Boccia Maria L |
| |
Institution: | Department of Psychiatry CB#7160, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. cpedersen@css.unc.edu |
| |
Abstract: | In previous studies, central administration of the oxytocin (OT) antagonist d(CH2)5Tyr(Me)2, Thr4, Tyr-NH(9)2]OVT (OTA1) blocked receptive and proceptive components of female sexual behavior (FSB) and increased male-directed agonistic behavior when given before progesterone (P) treatment in estradiol-primed female rats but not when given shortly before behavioral testing 4-6 h after P. Because the considerable V(1a) antagonist potency of OTA1 may have contributed to these results, we tested the effects of the far more selective OT antagonist desGly-NH2, d(CH2)5d-Tyr2, Thr4]OVT (OTA2). In ovariectomized, estradiol benzoate-primed (1 microg x 2 days sc) rats, icv infusion of OTA2 (1 microg) prior to P injection (250 microg sc) significantly suppressed lordosis and hops and darts and trended toward significantly increasing male-directed kicks during testing at 4 and 6 h. Infusion of OTA2 3 h and 40 min after P did not alter behavior at 4 and 6 h after P but significantly decreased lordosis as well as hops and darts and increased male-directed kicks 8-12 h after P. These results provide further evidence that central OT receptor activation shortly after P treatment contributes to the subsequent onset and early expression of FSB and demonstrate, for the first time, that OT receptor activation at later time points also contributes to maintaining FSB. The FSB-stimulating effect of central OT appears to persist for several hours. |
| |
Keywords: | oxytocin female sexual behavior lordosis proceptive behavior agonistic behavior antagonist progesterone estrogen estradiol |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|