Follicular Vascular Endothelial Growth Factor AExpression Before and After the LH Surge

Granulosa cell expression of VEGFA isoforms in dominant bovine follicles was evaluated. Collection of granulosa cells via follicle aspiration revealed altered expression of the proangiogenic VEGFA_164 isoform but not the antiangiogenic VEGFA_164B isoform prior to and after the LH surge. Expression of VEGFA_164 declines as both the LH surge and ovulation approaches . In addition, VEGFA_164 and VEGFA_164B expression prior to the LH surge was positively correlated with FSHR and CYP19A1 expression, suggesting that VEGFA expression may be regulated by FSH. These data indicate differential expression of VEGFA isoforms may be an important feature of bovine dominant follicle development.