Supraoptic Neurosecretory Cells: Autonomic Modulation

Neurosecretory cells in the supraoptic nuclei of anesthetized cats were antidromically identified by electrical stimulation of the posterior pituitary. The responses of these units to afferent volleys from vagal and carotid sinus nerves were examined with a computer of average transients. Synaptic excitation of neurosecretory cells by stimulation of these pathways demonstrates the existence of excitatory inputs from vagal and carotid sinus nerve afferents. Since these pathways are involved in the release of antidiuretic hormone, the results support the hypothesis that its release is related to an increase in discharge frequency of supraoptic neurosecretory cells.