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Storage of biogenic amines in guinea-pig brain synaptosomes: influence of proton gradient and membrane potential.
- Source :
-
British journal of pharmacology [Br J Pharmacol] 1983 Jan; Vol. 78 (1), pp. 111-6. - Publication Year :
- 1983
-
Abstract
- 1 The effects of K(+), NaCN and the ionophores monensin, nonactin and carbonyl-cyanide-p-trifluoro-methoxyphenylhydrazone (FCCP) on the contents of [(3)H]-5-hydroxytryptamine ([(3)H]-5-HT), [(3)H]-dopamine and [(3)H]-noradrenaline ([(3)H]-NA) in guinea-pig synaptosomes preloaded with these amines were measured.2 In the presence of Ca(2+), K(+) markedly reduced the amine content of the synaptosomes, indicating an acceleration of spontaneous amine release. In the absence of Ca(2+), K(+) had much less effect.3 Monensin, nonactin and FCCP caused a release of all the three labelled amines. This release was considerably faster and more marked than that induced by K(+) and showed no dependence on Ca(2+). The ionophores did not release lactate-dehydrogenase from synaptosomes.4 NaCN, a blocker of oxidative energy production, did not enhance the spontaneous release of [(3)H]-5-HT nor did it influence the monensin-induced release of [(3)H]-5-HT.5 It is concluded that (a) the intragranular storage of 5-HT, dopamine and NA is dependent on the maintenance of a pH-gradient across the granular membrane as well as on the granular membrane potential; (b) the ionophores cause a non-exocytotic release of granular amines, and (c) blood platelets are partial models for aminergic brain neurones as far as intragranular amine storage is concerned.
- Subjects :
- Animals
Anti-Bacterial Agents pharmacology
Calcium physiology
Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone pharmacology
Guinea Pigs
Hydrogen-Ion Concentration
In Vitro Techniques
L-Lactate Dehydrogenase metabolism
Macrolides
Membrane Potentials
Monensin pharmacology
Potassium pharmacology
Protons
Biogenic Amines metabolism
Brain metabolism
Synaptosomes metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0007-1188
- Volume :
- 78
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- British journal of pharmacology
- Publication Type :
- Academic Journal
- Accession number :
- 6297644
- Full Text :
- https://doi.org/10.1111/j.1476-5381.1983.tb09369.x