Temporal Patterns of Neural Activity and Their Relation to the Secretion of Posterior Pituitary Hormones1

Abstract

Present knowledge of the electrophysiological correlates of neurosecretion is much more extensive for the hypothalamic magnocellular system than for its parvicellular counterparts controlling the secretions of the anterior lobe of the pituitary gland. The magnocellular endocrine neurones of the hypothalamic supraoptic and paraventricular nuclei, which synthesize the two hormones oxytocin and vasopressin, are well characterized histologically and biochemically, and vatious dcctrophysiological techniques are used to record their spiking activity. Moreover, hormone secretion can be induced by natural or experimental stimuli, and biological methods are available to assay the released hormones within seconds in the living animal.