Effects of collagenase on the release of [3H]-noradrenaline from bovine cultured adrenal chromaffin cells

摘要: Bovine isolated adrenal chromaffin cells maintained in culture at 37 degrees C for 1-7 days become polygonal and bipolar, with typical varicosity-like extensions. Catecholamine levels dopamine beta-hydroxylase activity decreased after 24-48 h of culture, but recovered to normal 3-7 later. Incubation day-old the presence increasing concentrations [3H]-noradrenaline (3.91 125 nM) resulted retention by amounts radioactivity directly proportional amine present media. One took up retained only one third found 2-7 cells. The addition collagenase cultured caused a decrease uptake tritium. However, enzyme treatment did not affect taken cell before treatment. Release tritium from evoked nicotine, acetylcholine (ACh) or 59 mM K+ was very poor 24 h-old cells; secretory response ACh dramatically increased culture. Bethanecol cause any response. When treated collagenase, which had fully their response, lost again ability release nicotine. responses high K+, veratridine ionophore X537A were affected. nicotinic two data suggest that use disperse adrenomedullary tissue during isolation procedure might be responsible young Since specifically impairs cholinoceptor-mediated catecholamine release, it seems likely is exerting its action on receptor complex. It unlikely either voltage-sensitive Na+ Ca2+ channels are affected as induced unaffected this enzyme.