Distribution of neurohypophysial hormones in the brain

The knowledge of the magnocellular neurohypophysial system has undergone a drastic change over the past decade. The system which was once considered to be involved solely in the release of oxytocin and vasopressin into the general circulation from the posterior pituitary is now correctly recognized as only part of a more elaborate and exceedingly complex system which not only modulates anterior pituitary function, but also intergrates a variety of other brain functions via long axonal projections from the hypothalamus to several extrahypothalamic sites. In addition, not only have vasopressin and oxytocin, and their carrier proteins been found in association with the magnocellular system, but a number of other peptide hormones have also been shown to exist within the same system. This paper attempts to bring together a growing body of anatomical (mainly immunocytochemical), biochemical and electrophysiological data and correlate them with the several physiological and behavioral effects that have been observed following the administration (both systemic and intracerebroventricular) of these nonapeptides.