Fig. 4

Relative gene expression of STAR, HSD3B2, CYP19A1 and GDF9 in equine granulosa cells in vitro. Equine granulosa cells collected by OPU were treated for 24 h either with 100 ng/ml IGF1 or with 20 µM H89 (PKA blocker) in the absence or presence of cortisol in the following dosages: 50 ng/ml, 100 ng/ml and 150 ng/ml, respectively. Experiments (n = 4 biological replicates) were conducted using pooled granulosa cells obtained from the ovaries of four to six mares for each experiment. A multivariate GLM was applied to test for the effects of IGF1, cortisol, as well as their interaction. In case of significant effects, pairwise comparisons after Bonferroni correction were performed. Relative gene expression is presented as determined by semi-quantitative real time (TaqMan) PCR (Xg ± SD). Significant differences and the respective P values are presented in each graph. Different superscripts indicate significant differences (P < 0.05) within each cortisol concentration, whereas bars indicate significant differences among different cortisol concentrations. *P < 0.05, ***P < 0.001