DIFFERENTIAL HYPOTHALAMUS BETA CATENIN EXPRESSION IN RATS WITH DEFICIENT LACTATION

NEIRA FLAVIA J; PENNACCHIO GISELA E; MACKERN OBERTI, JUAN PABLO; SOAJE MARTA; FANELLI MARIEL A.; JAHN GRACIELA A; VALDEZ SUSANA R

Mendoza

Congreso; XXXIV Reunión Anual de la Sociedad de Biología de Cuyo; 2016

Sociedad de Biología de Cuyo

Cadherins and catenins and their activation by Wnt proteinsparticipate in reproductive processes and interact with PRL signaling. Weexamined whether changes in the expression of Wnt/catenin proteins are involvedin lactation deficiency of OFA hr/hr rats by focusing on the regulationof PRL secretion at the hypothalamic level. Our first objective was tocharacterize the pattern of expression of β-catenin during the transitionbetween gestation and early lactation in OFA rats compared with Sprague Dawley (SD,their strain of origin). OFA and SD rats were decapitated at 12.00 h on days 19and 21 of gestation (G19, G21) or day 2 of lactation (L2). Serum PRL levelswere measured by RIA, and β-catenin expression in the medial basalhypothalamus was determined by Western blot. Comparison of β- cateninexpression through days under study, revealed that SD rats decreased β-cateninlevels at G21 and reestablished their values at L2, while OFA rats decreased proteinexpression only at L2 (p < 0.05). Comparison of β- catenin expression on thesame reproductive day revealed that SD rats had significantly lower values thanOFA rats at G21 (p< 0.05) and higher values at L2 (p < 0.05). Inconclusion, SD rats diminished β-catenin protein expresión at G21 while OFA reached the lowest expression at L2. These results suggest that OFA rats showaltered β-catenin expression linked with an increased dopaminergic tone andimpaired PRL release during lactation.