RT Journal Article
SR Electronic
T1 Opiate-Like Materials in the Adrenal Medulla: Evidence for Storage and Secretion with Catecholamines
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 1101
OP 1108
VO 16
IS 3
A1 O. HUMBERTO VIVEROS
A1 EMANUEL J. DILIBERTO, JR.
A1 ELI HAZUM
A1 KWEN-JEN CHANG
YR 1979
UL http://molpharm.aspetjournals.org/content/16/3/1101.abstract
AB Opiate-like materials, as measured by the radioreceptor assay, were found in the adrenal gland of 7 mammalian species including man. The opiate-like materials are confined to the adrenal medulla, and followed a pattern identical to catecholamines on differential and isopycnic centrifugation. In the isolated perfused dog adrenal gland, acetylcholine stimulates a Ca2+-dependent secretion of opiate-like materials and catecholamines in the same molar ratio as they are stored within the chromaffin cell. Ba2+ also stimulates the secretion of both products from the adrenal gland. Separation of the opiate-like materials by Sephadex G-50 and reverse phase high pressure liquid chromatography indicates the presence of four peaks of opiate-like materials of molecular weights below 2,000. Two of these peaks comigrate in these systems with authentic met- and leu-enkephalins and react with the corresponding antibodies. These results indicate that enkephalins and other low molecular weight opiate-like materials are stored in and secreted from the chromaffin vesicles with catecholamines in the adrenal glands. These findings support a role for enkephalins as neurotransmitters and/or neurohormones. Also, they suggest that enkephalins and other opiate-like materials may exert important neuroendocrine functions outside the central nervous system. ACKNOWLEDGMENTS The technical assistance of Mrs. Martha Abou-Donia, Ms. Pamela Allen and Mr. Mark Collins is gratefully acknowledged. We are grateful to Drs. Pedro Cuatrecasas and Charles A. Nichol for reviewing the manuscript, helpful discussions and constant encouragement. Human adrenal glands were obtained through the collaboration of Dr. Philip C. Pratt and his staff at the Veterans Administration Hospital, Durham, N. C.