Effects of Opioid Peptides Containing the Sequence of Met5-Enkephalin or Leu5-Enkephalin on Nicotine-Induced Secretion from Bovine Adrenal Chromaffin Cells
Article first published online: 12 DEC 2006
Journal of Neurochemistry
Volume 46, Issue 1, pages 1–11, January 1986
How to Cite
Marley, P. D., Mitchelhill, K. I. and Livett, B. G. (1986), Effects of Opioid Peptides Containing the Sequence of Met5-Enkephalin or Leu5-Enkephalin on Nicotine-Induced Secretion from Bovine Adrenal Chromaffin Cells. Journal of Neurochemistry, 46: 1–11. doi: 10.1111/j.1471-4159.1986.tb12918.x
- Issue published online: 12 DEC 2006
- Article first published online: 12 DEC 2006
- Received February 13, 1985; accepted May 21, 1985.
- Opioid peptides;
- Adrenal medulla;
- Chromaffin cells;
Abstract: Eighteen endogenous opioid peptides, all containing the séquence of either Met5- or Leu5-enkephalin, were tested for their ability to modify nicotine-induced secretion from bovine adrenal chromaffin cells. ATP released from suspensions of freshly isolated cells was measured with the luciferin-luciferase bioluminescence method as an index of secretion. None of the peptides affected 5 μM nicotine-induced ATP release at 10 nM. Three peptides inhibited secretion at 5 μM dynorphin,1-13, dynorphin1-9, and rimorphin inhibited by 65%, 37%, and 29% respectively. Use of peptidase inhibitors (bestatin, thiorphan, bacitracin, or 1,10-phenanthroline) did not result in any of the other peptides showing potent actions on the nicotinic response, although bestatin and thiorphan did enhance the inhibitory actions of dynorphin1-3 and dynorphin1-9 by 20–30%. Nicotine-induced secretion of endogenous catecholamincs from bovine chromaffin cells cultured for 3 days was also studied to assess any selective actions of the peptides on adrenaline or noradrenaline cell types. Dynorphin1-13 was 1,000-fold more potent than Leu5-enkephalin at inhibiting endogenous catecholamine secretion. Dynorphin1-13 was slightly more potent at inhibiting noradrenaline release than adrenaline release whereas Leu5-enkephalin showed the opposite selectivity. The structure-activity relationships of opioid peptide actions on the chromaffin cell nicotinic response are discussed in relation to the properties of the adrenal opioid binding sites.