Modulation of Cx43 and Gap Junctional Intercellular Communication by Androstenedione in Rat Polycystic Ovary and Granulosa Cells in vitro

Background: Gap-junctional intercellular communication (GJIC) is implicated in physicological processes and it is vitally important for granulosa cell (GC) differenti-ation and oocyte growth. We investigated the expression of connexin 43 (Cx43), a gap junctional protein, in normal and androstenedione-induced polycystic ovary (PCO), the effects of androstenedione on Cx43 expression, GJIC and progesterone production in granulosa cells in vitro. Methods: Isolated GCs from rat ovary were supplemented with FSH and dripped with EHS-matrix (EHS-drip) in culture media, were treated with physiological (10-7 M) or pathological (10-5 M) androstenedione concentrations to induce differentiation. Cx43 protein levels were assessed by Western blotting. Immunohistochemistry was also used to determine the localization of Cx43 in GCs and corpus luteum (CL) of controls and PCOs. Differentiation of GCs was determined by progesterone assay and Lucifer yellow dye transfer for GJIC status. The degree of significance of vari-ations between the results was analyzed by ANOVA using SPSS (version 11.5