Differential secretion of adrenaline and noradrenaline in response to various secretagogues from bovine chromaffin cells.
1. Differential secretion of adrenaline (Adr) and noradrenaline (NA) in response to various secretagogues was studied in bovine adrenal chromaffin cells. 2. Acetylcholine (ACh; 3-300 mumol/L), 1,1-dimethyl-4-phenyl-piperazinum (DMPP; 1-100 mumol/L), high K+ (20-60 mmol/L), calcimycin (1-100 mumol/L), histamine (0.3-30 mumol/L) and angiotensin (Ang)II (0.3-30 mumol/L) induced the secretion of a 1.3-2-fold greater percentage of NA stores than Adr stores in intact cells. 3. In beta-escin-permeabilized cells, Ca2+ (0.1-30 mumol/L) induced a greater secretion of Adr and NA in the presence of MgATP (2 mmol/L) than in the absence of MgATP. The percentage of NA secreted was 1.4- and 1.5-fold greater than that of Adr in the presence and absence of MgATP, respectively. 4. The ATP-independent phase of the Ca(2+)-dependent exocytosis is thought to be associated with the final step that ultimately leads to fusion, while the ATP-dependent phase is thought to be associated with the vesicle priming reaction. Therefore, the preferential secretion of NA in response to ACh, DMPP, high K+, calcimycin, histamine and AngII may be due, at least in part, to the greater effectiveness of Ca2+ in producing exocytosis in NA-containing cells.
Kuwashima
H
H
Department of Dental Pharmacology, Nippon Dental University School of Dentistry at Niigata, Japan. kuwajima@ngt.ndu.ac.jp
Matsumura
C
C
Kimura
T
T
D000109:Acetylcholine / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000502:physiology; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002417:Cattle; D002463:Cell Membrane Permeability / Q000187:drug effects; D019439:Chromaffin Cells / Q000187:drug effects* / Q000378:metabolism*; D004246:Dimethylphenylpiperazinium Iodide / Q000494:pharmacology; D004837:Epinephrine / Q000378:metabolism*; D004928:Escin / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D009638:Norepinephrine / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology
D000804:Angiotensin II; D000001:Calcimycin; D004246:Dimethylphenylpiperazinium Iodide; D004928:Escin; D006632:Histamine; D000255:Adenosine Triphosphate; D000109:Acetylcholine; D011188:Potassium; D001920:Bradykinin; D002118:Calcium; D009638:Norepinephrine; D004837:Epinephrine