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The neurohypophysis (pars posterior) is the posterior lobe of the pituitary gland, located at the base of the brain. The embryological origin of this structure is the neuroectodermal infundibulum. The neurohypophysis comprises 2 primary regions, the pars nervosa and the infundibular stalk. The pars intermedia and median eminence are sometimes included. The neurohypophysis secretes the 2 peptide hormones, oxytocin and vasopressin. Oxytocin stimulates uterine contractions and milk ejection. Vasopressin, also known as antidiuretic hormone (ADH), prevents diuresis.[1] These hormones are synthesized by magnocellular neurosecretory cells of the hypothalamus, specifically within the paraventricular and supraoptic nuclei. Axons from these neurons project to the neurohypophysis, transporting the hormones for storage and subsequent release into the neurohypophyseal capillaries, which deliver these neuropeptides to systemic circulation.[2] Dysfunction of the posterior pituitary disrupts hormonal homeostasis, causing arginine vasopressin deficiency (AVP-D) and the syndrome of inappropriate antidiuresis (SIAD). Disorders resulting from oxytocin deficiency are rare and primarily associated with pregnancy, lactation difficulties, osteopenia, and hyperphagia.[3] The posterior pituitary contains pituicytes. In the pars nervosa, these cells function as glial cells, providing structural support and modulating hormone release.