Altered expression of angiogenic factors in dominant preovulatory follicles of dairy cattle treated with ACTH.

Studies in cows have reported that ovulation, steroidogenesis and angiogenesis are affected by stress and consequently fertility decreases. The purpose of this study was to evaluate the effects of ACTH administration during the preovulatory period on the expression of growth factors (CD-31, PDGF-A, PDGF-B, VEGFA-164, VEGFA-164b, VEGF-R1 and VEGF-R2) associated with the angiogenic process by immunohistochemistry in cows (n = 14). Results evidenced the expression of these growth factors in theca and granulosa cells from antral, atretic and dominant preovulatory follicles of ACTH-treated cows, suggesting that, under stress conditions, their expression continues to be required.

Developmental Programming: Does Prenatal Steroid Excess Disrupt the Ovarian VEGF System in Sheep?

Prenatal testosterone (T), but not dihydrotestosterone (DHT), excess disrupts ovarian cyclicity and increases follicular recruitment and persistence. We hypothesized that the disruption in the vascular endothelial growth factor (VEGF) system contributes to the enhancement of follicular recruitment and persistence in prenatal T-treated sheep. The impact of T/DHT treatments from Days 30 to 90 of gestation on VEGFA, VEGFB, and their receptor (VEGFR-1 [FLT1], VEGFR-2 [KDR], and VEGFR-3 [FLT4]) protein expression was examined by immunohistochemistry on Fetal Days 90 and 140, 22 wk, 10 mo (postpubertal), and 21 mo (adult) of age.