Hypothalamus
A brain region that produces releasing and inhibiting hormones controlling pituitary function. The hypothalamus produces GHRH, somatostatin, GnRH, CRH, TRH, oxytocin, and vasopressin — many of which are templates for therapeutic peptide drugs or their direct targets.
Technical Context
The hypothalamus (approximately 4g, located below the thalamus) integrates neural and endocrine signals to regulate homeostasis. Key peptide-producing nuclei include: arcuate nucleus (GHRH, dopamine, kisspeptin, AgRP/NPY and POMC/CART neurons for appetite regulation), paraventricular nucleus (CRH, TRH, oxytocin, vasopressin), supraoptic nucleus (oxytocin, vasopressin), and preoptic area (GnRH). Hypothalamic peptides reach the anterior pituitary via the portal blood system and the posterior pituitary via direct axonal transport. The hypothalamus also contains GLP-1 receptors involved in appetite regulation — this is one mechanism by which GLP-1 RAs suppress appetite. Multiple peptide drug classes are derived from or target hypothalamic peptides.