Differential hypothalamic Beta Catenin expression in rats with deficient lactation.

NEIRA FJ; PENNACCHIO GE; MACKERN-OBERTI JP; SOAJE M; FANELLI MA; JAHN GA; VALDEZ SR

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

Sociedad de Biología de Cuyo

Cadherinsand catenins and their activation by Wnt proteins participate in reproductiveprocesses and interact with PRL signaling. We examined whether changes in theexpression of Wnt/catenin proteins are involved in lactation deficiency of OFAhr/hr rats by focusing on the regulation of PRL secretion at the hypothalamiclevel. Our first objective was to characterize the pattern of expression of β-cateninduring the transition between gestation and early lactation in OFA ratscompared with Sprague Dawley (SD, their strain of origin). OFA and SD rats weredecapitated at 12.00 h on days 19 and 21 of gestation (G19, G21) or day 2 oflactation (L2). Serum PRL levels were measured by RIA, and β-cateninexpression in the medial basal hypothalamus 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 decreasedprotein expression only at L2 (p < 0.05). Comparison ofβ-catenin expression on the same reproductive dayrevealed that SD rats had significantly lower values than OFA rats at G21 (p <0.05) and higher values at L2 (p <0.05). Inconclusion, SD rats diminished β-catenin proteinexpression at G21 while OFA reached the lowest expressionat L2. These results suggest that OFA rats show altered β-cateninexpression linked with an increased dopaminergic tone and impaired PRL releaseduring lactation