Expression and Localization of the Vascular Endothelial Growth Factor and Changes of Microvessel Density During Hair Follicle Development of Liaoning Cashmere Goats

This study investigated the expression and localization of vascular endothelial growth factor (VEGF) and changes in microvessel density (MVD) during hair follicle development in Liaoning cashmere goats. Using immunohistochemical examinations over a year, it was found that VEGF was expressed in various parts of the hair follicle and skin, with abundant expression in the follicular basement membrane and eccrine sweat glands. VEGF expression in primary and secondary hair follicles exhibited a bimodal pattern, peaking in March-May and August, and was synchronized with hair development. In later hair cycle phases, VEGF expression was higher in secondary follicles. MVD also showed a bimodal pattern, correlating strongly with VEGF expression, indicating their close relationship in hair cycle regulation.