CATECHOLAMINE UPTAKE BY ISOLATED CORONARY ARTERIES AND ATRIA OF THE KITTEN

摘要: Kitten coronary arteries and atria incubated with [3H]-(-)-noradrenaline or [3H]-(+/-)-isoprenaline showed concentration- temperature-dependent accumulation of amines (unchanged and/or as metabolites). In addition, temperature-insensitive amine due to binding connective tissue fibres. 2 With low concentrations (20 ng/ml) radioactivity in both tissues was neuronal since it reduced by desipramine, metaraminol cocaine but not the extraneuronal inhibitor, cortisol. 3 (5 microgram/ml) for 1 10 min, uptake inhibited cortisol, 17beta-oestradiol phenoxybenzamine. 4 Atria (+/-)-isoprenaline 1000 non-neuronal, biphasic amine. There a high capacity, affinity initial process (apparent Km 136 micron) which resistant steroidal inhibitors could be abolished A slower occurred after min sensitive other inhibitors. 5 Inhibition processes did alter sensitivity dilator effects catecholamines. However, experiments were limited relaxant cortisol themselves. 6 inhibition desipramine led supersensitivity (-)-noradrenaline (-)-adrenaline (+/-)-isoprenaline. Chronotropic responses increased five fold inotropic three fold.