Phorbol esters cause preferential secretion of norepinephrine from bovine chromaffin cells.
Differential secretion of norepinephrine and epinephrine was studied in cultured bovine chromaffin cells. Nicotinic agonists and 55 mM K+ evoked a slightly greater release of norepinephrine than of epinephrine: The percentage of norepinephrine secreted was 1.5 to two times greater than the percentage of epinephrine secreted. In contrast, when the cells were treated with phorbol 12,13-dibutyrate, the percentage of norepinephrine released was six to eight times greater than that of epinephrine released. Similar results were obtained in experiments with cultures highly enriched in either norepinephrine-containing cells or epinephrine-containing cells. In response to 55 mM K+, catecholamine release from norepinephrine-containing cells was two times greater than that from epinephrine-containing cells. In response to phorbol 12,13-dibutyrate, secretion from norepinephrine-containing cells was 13 times greater than that from epinephrine-containing cells. These results suggest that protein kinase C plays a specific role in the regulation of catecholamine secretion from norepinephrine-containing cells.
Cahill
A L
AL
Department of Pediatrics, University of Chicago, Illinois 60637.
Perlman
R L
RL
D000818:Animals; D002118:Calcium / Q000493:pharmacokinetics; D002417:Cattle; D002838:Chromaffin System / Q000166:cytology / Q000378:metabolism*; D004246:Dimethylphenylpiperazinium Iodide / Q000494:pharmacology; D004837:Epinephrine / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism*; D009994:Osmolar Concentration; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010703:Phorbol Esters / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology
D010703:Phorbol Esters; D015240:Phorbol 12,13-Dibutyrate; D004246:Dimethylphenylpiperazinium Iodide; D011188:Potassium; D002118:Calcium; D009638:Norepinephrine; D004837:Epinephrine