QPCR analysis of SERPINA5, SERPINB6, SERPINE1, SERPINE2, SERPINF2 and SERPING1 in healthy and atretic follicles. Total RNA from the follicular wall (i.e., granulosa plus theca interna) was extracted from three healthy follicles and three atretic follicles. The expression of mRNA was normalized to the expression of GAPDH measured in the same RNA preparation. The black and white bars indicate healthy and atretic follicles, respectively. Data are shown as the mean ± SEM. Different superscript letters denote significant differences (P < 0.05).