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Follicles - Anatomy & Physiology (view source)
Revision as of 18:40, 16 July 2008
, 18:40, 16 July 2008→function
==function==
==function==
*Follicular cells produce hormones important for the progression of the oestrus cycle. Theca cells produce Androstienedione which is converted to 17β-Oestrodiol (E2) by the Granulosa cell enzyme Aromatase. At low levels E2 acts to negatively feedback to the hypothalamus and pituitary gland, inhibiting production of Gonadotrophin releasing Hormone (GnRH) and LH + FSH respectively. When the E2 level increases above the level of threshold it acts to stimulate gonadotrophin release. This results in the LH surge responsible for Ovulation.
*The positive feedback action of E2 leading to a surge in LH only and not FSH is due to the selective action of Inhibin. Inhibin is a hormone produced by granulosa cells that selectively inhibits FSH production by the pituitary gland.