Ganglionic effect of prolactin on the luteal regression on day 4 pospartum in non-lactating rats

VALLCANERAS S, ; CASAIS M; ANZULOVICH AC; RASTRILLA AM

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

GANGLIONIC EFFECT OF PROLACTIN ON THE LUTEAL REGRESSION ON DAY 4 POSTPARTUM IN NON-LACTATING RATS Vallcaneras S, Casais M, Motta A, Rastrilla AM   Lab Biol Reprod (LABIR) - FQByF-UNSL - San Luis, Chacabuco 917. (ssvallca@unsl.edu.ar)   The luteotrophic/luteolytic effect of prolactin (PRL) is dependent of the nature of the corpus luteum (CL) and the hormonal environment to which it is exposed. The aim of this study was to investigate the effect of PRL in the coeliac ganglion (GC), through superior ovarian nerve (NOS) on luteal regression on day 4 pospartum of non-lactating rats. The system GC-NOS-ovary was used, which was incubated in Krebs Ringer buffer at 37 °C, keeping the GC and the ovary connected by NOS, in separate compartments. PRL was added (10-7M) into the ganglion compartment [(PRL)g]. Controls were not stimulated. Periodic extractions of the ovary incubation liquid were taken at different times along 240 min to measure of progesterone (P) and PGF2alpha by RIA and nitrites by the Griess method. At 240 min, the luteal mRNA expression of 3beta-HSD, 20alpha-HSD, PGF2alpha receptor, iNOS, bcl-2 and bax were analysed by RT-PCR. ANOVA I followed by Tuckey test with a statistical significance of p <0.05 was used. [(PRL)g] increased the release of P and modified the expression of 3beta-HSD and 20lpha-HSD; increased the release of nitrites without modify the expression of iNOS and increased the release of PGF2alpha and decreased the expression of its receptor respect to the control. PRL, neural pathway, would promote the luteal regression through the ovarian luteolytic factors: ON and PGF2alpha in the presence of high levels of ovarian P.