Vascular endothelial growth factor-A₁₆₅ (VEGF-A₁₆₅) stimulates the in vitro development and oocyte competence of goat preantral follicles

摘要

The aim of this study was to evaluate the effect of vascular endothelial growth factor-A₁₆₅ (VEGF-A₁₆₅) on the in vitro development of goat secondary preantral follicles. Preantral follicles (≥150 μm in diameter) were isolated from the ovaries of adult mixed-breed goats and individually cultured for 18 days in αMEM in the absence (control) or presence of VEGF-A₁₆₅ at concentrations of 10 ng/ml (VEGF10) and 100 ng/ml (VEGF100). Analyses of follicular survival, diameter, antrum formation and rate of daily growth were performed every 6 days. At the end of the culture period, morphologically normal oocytes (≥110 μm in diameter) were taken for in vitro maturation (IVM). The results demonstrated that all follicles presented oocytes and granulosa cells that were morphologically normal and after labeling with calcein-AM, high rates of oocyte viability were observed in all treatments. The follicular diameter and the growth rate achieved in the presence of VEGF10 were higher than those of the control. Both treatments with VEGF-A₁₆₅ showed higher rates of oocyte recovery for IVM when compared with the control. Moreover, only the addition of VEGF-A₁₆₅ permitted oocytes grown in vitro to reach metaphase II. Thus, the addition of VEGF-A₁₆₅ to the culture medium improves the development of goat preantral follicles cultured in vitro, allowing the production of mature oocytes.