Figure 1.

Gonadotropin-dependent expression of NRG1 and the ErbB family of receptors in GCs. Immature rats (23 days old) were treated with or without PMSG for different lengths of time. (a) Representative WB analysis of protein levels of NRG1 and ErbB receptors in GCs isolated from two ovaries per rat per sample. Equal amounts of protein were applied to each lane. α-Tubulin was used as an internal control. Bar diagrams represent the densitometric analyses of protein in WBs. MCF-7 cell line protein extract was used as a positive control; BSA was used as negative control. *P ≤ 0.05 relative to control group. (b, c) Immunocolocalization of endogenous NRG1 with Alexa Fluor 594-labeled (red) secondary antibody in gonadotropin-treated rat ovary at (b) 24 and (c) 48 hours (n = 3 rats per time point). Representative photomicrographs of whole ovary at 24 and 48 hours are depicted separately. The nucleus was counterstained with 4′,6-diamidino-2-phenylindole (blue). Bar diagrams represent the mean fluorescence intensity of Alexa Fluor 594 in GCs and theca cells in preantral, small antral, and large antral follicles at (b) 24 and (c) 48 hours. *P ≤ 0.05 relative to NRG1 expression between GCs and theca cells in preantral and small and large antral follicles. All the data and numerical values (presented as mean ± standard error of the mean) are represented from three independent experiments performed for each individual group. a, antrum; BSA, bovine serum albumin; o, oocyte; TIC, theca-interstitial cell.