Catecholamine release from fractionated chromaffin cells.
Bovine chromaffin cells were separated by density gradient centrifugation into subfractions. After centrifugation on a self-generating Percoll gradient (42.75% isotonic Percoll, 30,000 x g for 22 min at 20 degrees C), the chromaffin cells were found in two clearly distinguishable peaks. The peak with the lower density contained most of the noradrenaline-producing cells (approximately 80%), whereas the adrenaline-producing cells were equally distributed between the two peaks. After collection of suitable fractions from the gradient, cell cultures were obtained, which were enriched with either > 90% adrenaline- or approximately 65% noradrenaline-producing cells. When stimulated by nicotine or carbachol, the dose-response curves of both cell fractions yielded similar EC50s for the release of adrenaline and noradrenaline. On the other hand, the cells of the less dense fraction released 30% more catecholamines (adrenaline as well as noradrenaline) than the cells of the more dense fraction. It is suggested that there are subpopulations among the adrenaline- and noradrenaline-producing cells with differences in receptor-effector coupling.
Krause
W
W
Research Institute of Molecular Pharmacology, Berlin, Germany.
Michael
N
N
Lübke
C
C
Livett
B G
BG
Oehme
P
P
D000322:Adrenergic Agonists / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000818:Animals; D002217:Carbachol / Q000037:antagonists & inhibitors / Q000494:pharmacology; D002417:Cattle; D002469:Cell Separation; D019439:Chromaffin Cells / Q000166:cytology / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000378:metabolism*; D018738:Hexamethonium / Q000494:pharmacology; D006801:Humans; D016210:Methacholine Chloride / Q000494:pharmacology; D018721:Muscarinic Agonists / Q000494:pharmacology; D009538:Nicotine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D018722:Nicotinic Agonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology; D009638:Norepinephrine / Q000378:metabolism* / Q000494:pharmacology
D000322:Adrenergic Agonists; D000316:Adrenergic alpha-Agonists; D018721:Muscarinic Agonists; D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D016210:Methacholine Chloride; D018738:Hexamethonium; D009538:Nicotine; D002217:Carbachol; D009638:Norepinephrine; D004837:Epinephrine