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The hypothalamus influences the pituitary through releasing and inhibiting hormones, while the pituitary relays signals through distinct anterior and posterior divisions. The anterior pituitary is regulated through the portal system and secretes TSH, ACTH, LH, FSH, GH, and prolactin. The posterior pituitary is connected to the hypothalamus by neurons and releases ADH and oxytocin synthesized there. Hormone output is shaped by feedback: negative feedback is most common, while positive feedback temporarily amplifies responses. Pulsatile release, particularly of GnRH and GH, supports receptor sensitivity and physiological function. Clinical examples include anterior pituitary failure after postpartum hemorrhage in Sheehan syndrome and prolactinoma, which may cause galactorrhea and amenorrhea.