Influences of gonadotropin-releasing hormone and nitric oxide on luteal regression through the peripheral neural pathway

FILIPPA, VERONICA P; MORALES, LAURA; VALLCANERA, SANDRA; AGUILERA MERLO, CLAUDIA I; CASAIS, MARILINA

San Luis

Congreso; XXXVII Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2020

Sociedad de Biología de Cuyo

Using the Coeliac Ganglion-Superior Ovarian Nerve-Ovary system (CG-SON-Ov) of late pregnant rat, we have physiologically demonstrated the presence of GnRH/GnRH-receptor system in CG and the influence of NO on the ganglionic GnRH favoring its release. In addition, taking into account that the peripheral neural system can act as a modulator of corpus luteum of pregnancy (CL), the objective of this work was to investigate the effect of cetrorelix (CTX) and L-NAME from CG, through the SON, on functional and structural luteal regression markers.The CG-SON-Ov system, extracted from rats with 21 days of pregnancy, was incubated in Krebs Ringer at 37ºC, keeping CG and Ov connected by the SON, in separate compartments, during 180 min. The experimental groups (n=6 in each experimental group) consisted in the addition in the ganglionic compartment of: a) CTX, GnRH receptor antagonist (10-6 M), b) L-NAME (NG-nitro-l-arginine methyl ester), an inhibitor of nitric oxide synthase (100 μM), c) L-NAME (100 μM) + CTX (10-6 M). Control group consisted of CG-SON-Ov systems that were untreated. Progesterone (P), the main steroid secreted by the CL, was determined by RIA in the ovarian compartment and the luteal mRNA expression of P synthesis and degradation enzymes, 3 beta-hydroxysteroid dehydrogenase (3β-HSD) and 20 alfa-hydroxysteroid dehydrogenase (20α-HSD) respectively, were assessed by RT-PCR. Apoptotic cells were detected by TUNEL in ovarian tissue sections. The data were statistically analyzed using one-way ANOVA and post-hoc Tukey test (p