Dynorphin-A-(1-8) is contained within vasopressin neurosecretory vesicles in rat pituitary

Science  09 Dec 1983:
Vol. 222, Issue 4628, pp. 1137-1139
DOI: 10.1126/science.6648526


Dynorphin-A-(1-8), an opioid peptide widely distributed in the rat central nervous system, is present in vasopressin-containing neurosecretory cells terminating in the neural lobe of the pituitary. Electron microscopic immunocytochemistry reveals that dynorphin-A-(1-8) is contained within the same neurosecretory vesicles as vasopressin and vasopressin-associated neurophysin in the neural lobe of the rat. The results indicate that dynorphin may be released in the pituitary concomitantly with vasopressin during the antidiuretic response.