Effects of nerve growth factor (NGF) on blood vessels area and expression of the angiogenic factors VEGF and TGFbeta 1 in the rat ovary

Abstract

Background: Angiogenesis is a crucial process in follicular development and luteogenesis. The nerve growth factor (NGF) promotes angiogenesis in various tissues. An impaired production of this neurotrophin has been associated with delayed wound healing. A variety of ovarian functions are regulated by NGF, but its effects on ovarian angiogenesis remain unknown. The aim of this study was to elucidate if NGF modulates 1) the amount of follicular blood vessels and 2) ovarian expression of two angiogenic factors: vascular endothelial growth factor (VEGF) and transforming growth factor beta I (TGFbetaI), in the rat ovary. Results: In cultured neonatal rat ovaries, NGF increased VEGF mRNA and protein levels, whereas TGFbetaI expression did not change. Sectioning of the superior ovarian nerve, which increases ovarian NGF protein content, augmented VEGIF immunoreactivity and the area of capillary vessels in ovaries of prepubertal rats compared to control ovaries. Conclusion: Results indicate th