The synthesis and secretion of Regulation of Sex hormone estrogens is stimulated by follicle- stimulating hormone (FSH)(卵泡 邀素)which is,in turn, controlled by the hypothalamic Hypothalamus gonadotropin releasing hormone GnRH (GnRH)(促性腺邀素释放邀素)， Hypothalamus(下丘脑) Pituitary →GnRH→Pituitary(垂体) →FSH→Follicle→Estrogens FSH LH Gonadal Gonad Hypothalamus→GnRH→ peptides Pituitary-luteinizing Sex Steroids hormone(LH)(黄体刺邀 E,P,T Gametogenesis 素)→Testes→Testosterone Secondary Sex Characteristics The level of testosterone is under Fig.1.The hypothalamic-pituitary-gonadal axis.GnRH,gonadotropin-releas- negative-feedback control:a rising ing hormone;FSH,follicle-stimulating hormone:LH,luteinizing hormone;E. estrogen:P.progesterone:T.testosterone. level of testosterone suppresses the release of GnRH from the Sex steroid effects at target tissues:mechanisms of action hypothalamus. Margaret E.Wierman Advan in Physiol Edu 31:26-33,2007.:Regulation of Sex hormone The synthesis and secretion of estrogens is stimulated by follicle‐ stimulating hormone (FSH)（卵泡 刺激素） , which is, in turn, controlled by the hypothalamic gonadotropin releasing hormone (GnRH)（促性腺激素释放激素）. Hypothalamus（下丘脑） → GnRH→ Pituitary（垂体） → FSH→Follicle→ Estrogens Hypothalamus→GnRH→ Pituitary→luteinizing hormone(LH)(黄体刺激 素 )→Testes→Testosterone The level of testosterone is under negative‐feedback control: a rising level of testosterone suppresses the release of GnRH from the hypothalamus