Table 2-2. HORMONES OF REPRODUCTION
Hormone Chemical Nature Sites of Synthesis Target Primary Actions
NEUROHORMONES:
GnRH decapeptide hypothalamus anterior pituitary FSH and LH production
PRF TRH, serotonin hypothalamus anterior pituitary PRL production
PIF DA, GABA, GAP hypothalamus anterior pituitary inhibit PRL secretion
oxytocin nonapeptide hypothalamus uterus smooth muscle contraction (labor)
mammary gland milk let-down
melatonin indolamine pineal gland hypothalamus seasonal control of GnRH
GONADOTROPINS:
FSH, LH glycoprotein anterior pituitary gonad steroidogenesis, gametogenesis
PMSG glycoprotein placenta ovary follicular growth, accessory CL formation
hCG glycoprotein placenta ovary luteal maintenance during early pregnancy
prolactin protein anterior pituitary ovary luteotropin
mammary gland milk synthesis
hypothalamus maternal behavior
GONADAL PROTEINS:
inhibin glycoprotein gonad anterior pituitary inhibit FSH secretion
relaxin polypeptide ovary, placenta uterus, pelvis mechanism of parturition
MIH glycoprotein fetal testis Mullerian duct duct regression (XY embryo)
STEROID HORMONES:
P4, T, E2 sex steroids gonad, placenta brain feedback control of LH, sexual behavior
reproductive tract development, contractility
mammary gland development
other secondary sex characteristics
cortisol glucocorticoid adrenal cortex placenta induction of parturition