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Testes

ENDOCRINE PHYSIOLOGY

Hypothalamus

GnRH

Leydig

celi

Androgen-binding

protein

|. Perkins

MS. MfA

^CWN

Figurę 8.26 Control of Testicular Funciion-

Ihe testes are under the control of luteinizing hormone <LH) and fol-licle stimulating hormone (FSH), and their secretion from the anterior pituitary is conlrollerl by gonadotropin-releasing hormone (GnRI I) from the hypothalamus. LH acts on the interstitial I eydig cells to stimulate their production of testostorono. FSH acts on the Sertoli cells to stimulate their production of androgen-binding protein.

which then concentrates testosterone in the seminiferous tubules and thereby supports and promotes spermatogcncsis. Testosterone provides negative feedback inhibition of LH release, whereas inhibin produced by the Sertoli cells provides negative feedback inhibition of FSH secrelion.

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