Theca of follicle

Theca cells are responsible for synthesizing androgens, providing signal transduction between granulosa cells and oocytes during development by the establishment of a vascular system, providing nutrients, and providing structure and support to the follicle as it matures. FSH induces the granulosa cells to synthesize aromatase, an enzyme that converts the androgens made by the theca interna into estradiol. Disorders Hyperactivity of theca cells causes hyperandrogenism, and hypoactivity leads to a lack of estrogen. Thecomas are benign proliferations of theca cells that may present with hormonal dysfunction. Theca cells (along with granulosa cells) form the corpus luteum during oocyte maturation. Theca cells are only correlated with developing ovarian follicles. They are the leading cause of endocrine-based infertility, as either hyperactivity or hypoactivity of the theca cells can lead to fertility problems. == Folliculogenesis ==

In human adult females, the primordial follicle is composed of a single oocyte surrounded by a layer of closely associated granulosa cells. In early stages of the ovarian cycle, the developing follicle acquires a layer of connective tissue and associated blood vessels. This covering is called the theca. As development of the secondary follicle progresses, granulosa cells proliferate to form the multilayered membrana granulosum. Over a period of months, the granulosa cells and thecal cells secrete antral fluid (a mixture of hormones, enzymes, and anticoagulants) to nourish the maturing ovum. In tertiary follicles, the single-layered theca differentiates into a theca interna and theca externa. The theca interna contains glandular cells and many small blood vessels, while the theca externa is composed of dense connective tissue and larger blood vessels. ==See also==