Methionine-enkephalin and leucine-enkephalin in human sympathoadrenal system and pheochromocytoma.
Open Access
- 1 March 1982
- journal article
- research article
- Published by American Society for Clinical Investigation in JCI Insight
- Vol. 69 (3), 643-650
- https://doi.org/10.1172/jci110491
Abstract
To elucidate the physiological and pathophysiological significance of methionine- and leucine-enkephalin (Met-and Leu-enkephalin, respectively) in human sympathoadrenal system, the contents of these peptides in normal human sympathetic nervous system, adrenal medulla, and pheochromocytomas were determined by specific radioimmunoassays combined with reverse-phase high-performance liquid chromatography. Met-enkephalin-LI and Leu-enkephalin-LI, respectively) were detected by radioimmunoassay in adrenal glands, adrenal medulla, stellate ganglia, sympathetic trunks, and celiac ganglia, and their contents in adrenal medulla were highest. Existence of authentic Met- and Leu-enkephalin was confirmed by reverse-phase high-performance liquid chromatography. Met-enkephalin was approximately 74% of Met-enkephalin-LI, whereas Leu-enkephalin was approximately 30% of Leu-enkephalin-LI in human adrenal medulla. The ratio of Met- to Leu-enkephalin was 2.6 in human adrenal medulla, whereas it was higher in sympathetic ganglia or trunks. In four cases of pheochromocytoma marked difference in Met- and Leu-enkephalin contents was found between medullary and extramedullary tumors. The contents were about three orders higher and the Met- to Leu-enkephalin ratio was lower in medullary than in extramedullary pheochromocytomas, reflecting the tissues where the tumors arose. These results suggest the physiological roles of Met- and Leu-enkephalin in sympathetic nervous system and adrenal glands and their pathophysiological significances in pheochromocytomas.This publication has 20 references indexed in Scilit:
- Biochemical characterization of enkephalin-like immunoreactive peptides of adrenal glandsLife Sciences, 1980
- Isolation of human met-enkephalin and two groups of putative precursors (2K-pro-met-enkephalin) from an adrenal medullary tumourBiochemical and Biophysical Research Communications, 1980
- Enkephalin in bovine adrenal gland: Multiple molecular forms of [met5]-enkephalin immunoreactive peptidesNeuropharmacology, 1980
- Met-enkephalin circulates in human plasmaNature, 1980
- Decreased content of immunoreactive enkephalin-like peptide in peripheral tissues of spontaneously hypertensive ratsNature, 1979
- RADIOIMMUNOASSAY OF METHIONINE‐AND LEUCINE‐ENKEPHALINS IN REGIONS OF RAT BRAIN AND COMPARISON WITH ENDORPHINS ESTIMATED BY A RADIORECEPTOR ASSAYJournal of Neurochemistry, 1978
- ENKEPHALIN IN PERIPHERAL NEUROENDOCRINE TUMOURSThe Lancet, 1978
- Enkephalin pentapeptides — A review of current evidence for a physiological role in vertebrate neurotransmissionLife Sciences, 1977
- Identification of two related pentapeptides from the brain with potent opiate agonist activityNature, 1975
- Preparation of Iodine-131 Labelled Human Growth Hormone of High Specific ActivityNature, 1962