Hormone Structure Primary Action on Anterior Pituitary Thyrotropin-releasing hormone (TRH) Peptide of 3 amino acids Stimulates secretion of
TSH by thyrotropes
Gonadotropin-releasing hormone (GnRH) Single chain of 10 amino acids Stimulates
secretion of FSH and LH by
Gonadotropes Corticotropin-releasing hormone (CRH) Single chain of 41 amino acids
Stimulates secretion of ACTH by
Corticotropes Growth hormone-releasing hormone (GHRH) Single chain of 44 amino
acids Stimulates secretion of growth hormone by Somatotropes Growth hormone inhibitory
hormone (somatostatin) Single chain of 14 amino acids Inhibits secretion of growth hormone
by somatotropes Prolactin-inhibiting hormone (PIH) Dopamine (a catecholamine) Inhibits
synthesis and secretion of prolactin by lactotropes Table 75-2 Hypothalamic Releasing and
Inhibitory Hormones That Control Secretion of the Anterior Pituitary Gland
ACTH, adrenocorticotropic hormone; FSH, follicle-stimulating hormone;