Arcuate Nucleus Of The Hypothalamus (Side View)

Description

Arcuate nucleus of the hypothalamus lies along the inferomedial wall and floor of the third ventricle, immediately superior to the median eminence in the region of the tuber cinereum. From a fixed lateral perspective, the nucleus sits anterior to the mammillary body and posterior to the optic chiasm, hugging the ventral surface of the diencephalon near the infundibular recess. Its position places it just dorsal to the pituitary stalk (infundibulum), where hypothalamic neurons interface with the hypophyseal portal system. Neuroendocrine and energy balance circuits converge here. Pro-opiomelanocortin (POMC) and neuropeptide Y/agouti-related peptide (NPY/AgRP) populations integrate leptin, insulin, and ghrelin signaling and project toward other hypothalamic targets, a relationship that frames clinical discussions of obesity, cachexia, and hypothalamic injury after suprasellar surgery or radiotherapy. The arcuate also contains kisspeptin-neurokinin B-dynorphin (KNDy) neurons that coordinate GnRH pulsatility, so its ventral adjacency to the third ventricle and median eminence is not just topography, it explains why functional disruption can present as hypogonadotropic hypogonadism or functional hypothalamic amenorrhea. Use this illustration in neuroanatomy and endocrine teaching blocks to orient learners to the arcuate nucleus relative to the third ventricle, median eminence, and infundibulum, or in clinical publications covering appetite regulation, bariatric neurobiology, or hypothalamic-pituitary axis disorders. It also fits neurosurgical and neuroradiology atlases when labeling ventral hypothalamic landmarks around the suprasellar cistern. Anatomical accuracy verified by SciePro's Medical Advisory Board.