Neurohypophysial Hormones in the Adrenal Medulla*

Abstract

Immunoreactive oxytocin and arginine vasopressin (AVP) were measured in the adrenal medulla of both rat and man as well as in tissue from two pheochromocytomas using highly specific RIAs. In all instances, oxytocin predominated over AVP. The concentrations of oxytocin ranged from 19.9-162.7 pg/g tissue, whereas those for AVP were 9.8-102 pg/g. These values are far greater than those found in plasma. The oxytocin- and AVP-related neurophysins were also present in large quantities in human adrenal medulla and pheochromocytoma. Identity of the peptides was confirmed by demonstrating parallel immunoreactivity with standard compounds and by the high performance liquid chromatographic profiles. In experiments carried out in rats, the source of the adrenal medullary AVP and oxytocin did not appear to be the paraventricular nucleus. It is postulated that the neurohypophysial peptides may have a regulatory function in the secretion of catecholamines.

The natural history of the chromaffin cell. Twenty-five years on the beginning.

“…In addition to the ubiquitous neuropeptides associated with chromaffin cells and the peripheral autonomic nervous system such as enkephalins, vasoactive intestinal peptide, substance P, neuropeptide Y, calcitonin gene-related peptide, somatostatin and neurotensin, atrial natriuretic peptide- (DELEAN et al, 1985;PRUSS andZAMIR, 1987) oxytocin-andvasopressin-(ANG andJENKINS, 1984 ;HAWTHORNE et al, 1987) and corticotropin-releasing-like immunoreactivity (HASHIMOTO et al, 1984) have been reported in chromaffin cells in a variety of mammalian species.…”

On the mechanisms of k‐opioid‐induced diuresis

“…However, vasopressin has recently been identified in the rat adrenal medulla (Ang & Jenkins, 1984) and evidence is now presented to show that the diuretic response to the recently described K-agonists tifluadom (Romer et al, 1982a, b), U50488 (Von Voigtlander et al, 1983) and ethylketocyclazocine (EKC; Iwamoto & Martin, 1981) may involve a peripheral component, dependent upon an intact and functional adrenal medulla. A preliminary account of these results has been presented to the British Pharmacological Society (Blackburn et al, 1985).…”

Studies on the adrenomedullary dependence of κ‐opioid agonist‐induced diuresis in conscious rats

“…The adrenal medulla contains numerous endogenous transmitters and hormones (Ang & Jenkins, 1984;Lemaire et al, 1984), yet catecholamines comprise the major portion of the adrenomedullary contents (Kirshner, 1972). Thus, the effectiveness of adrenal demedullation was assessed by measuring plasma adrenaline and adrenal gland catecholamine content.…”

“…The identification of opioid receptors (Castanas et al, 1984) and immunoreactivity to vasopressin (Ang & Jenkins, 1984) in the adrenal medulla, raised the possibility that the diuretic response to K-opioid agonists might involve a peripheral component, dependent upon an intact and functional adrenal medulla (Blackburn et al, 1985;1986). Indeed, adrenal demedullation was found to abolish selectively the diuretic response to the K-opioid agonists, U50488H, ethylketocyclazocine (EKC) and tifluadom (Blackburn et al, 1986).…”