caa a22 4500 46912136X CHVBK 20180323133140.0 cr unu---uuuuu 170328e19920301xx s 000 0 eng 10.1007/BF02245424 doi (NATIONALLICENCE)springer-10.1007/BF02245424 Bilateral injections of a selective μ -receptor agonist (morphiceptin) into the medial preoptic nucleus produces a marked delay in the initiation of sexual behavior in the male rat [Elektronische Daten] [Leslie Matuszewich, Wayne Dornan] We examined the putative functional role of the medial preoptic nucleusμ-receptor population in the expression of male copulatory behavior in sexually vigorous Long-Evans rats. In the first experiment, three doses of morphiceptin (10, 500, and 1000 ng) a selectiveμ-receptor agonist injected bilaterally into the medial preoptic nucleus, produced a marked delay in the initiation of male copulatory behavior compared to saline injected controls. These injections significantly lengthened intromission and mount latencies while having no appreciable effect on any other parameter of male copulatory behavior. In a separate experiment, the transient inhibition of the expression of male copulatory behavior was completely abolished following pretreatment of naloxone 20 minutes prior to bilateral injections of morphiceptin (1000 ng) into the medial preoptic nucleus. Collectively, these results suggest that the delay in the initiation of copulation that is commonly observed following peripheral or central injections of opioids is mediated at least in part byμ receptors located within the medial preoptic nucleus. Springer-Verlag, 1992 Masculine sexual behavior nationallicence Medial preoptic nucleus nationallicence Opioid peptides nationallicence Morphiceptin nationallicence μ -receptors nationallicence Matuszewich Leslie Department of Psychology, Illinois Wesleyan University, 61701, Bloomington, IL, USA aut Dornan Wayne Department of Psychology, Illinois Wesleyan University, 61701, Bloomington, IL, USA aut Psychopharmacology Springer-Verlag 106/3(1992-03-01), 391-396 0033-3158 106:3<391 1992 106 213 https://doi.org/10.1007/BF02245424 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02245424 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Matuszewich Leslie Department of Psychology, Illinois Wesleyan University, 61701, Bloomington, IL, USA aut NATIONALLICENCE 700 1- Dornan Wayne Department of Psychology, Illinois Wesleyan University, 61701, Bloomington, IL, USA aut NATIONALLICENCE 773 0- Psychopharmacology Springer-Verlag 106/3(1992-03-01), 391-396 0033-3158 106:3<391 1992 106 213 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer