Vasopressin is secreted by

Supraoptic nucleus (nucleus supraopticus) one just above the lateral pa of the optic chiasm; many of its cells are neurosecretory in function and project to the neurohypophysis, where they secrete antidiuretic hormone (ADH) and, to a lesser extent, oxytocin; other cells are osmoreceptors that stimulate ADH release in response to increased osmotic pressure.Ref: Ganong&;s review of medical physiology; 24th edition;