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Adenylyl cyclase activation by halide anions other than fluoride

1974; Elsevier BV; Volume: 61; Issue: 2 Linguagem: Inglês

10.1016/0006-291x(74)91025-0

1090-2104

Martin I. Kalish, Marco A. Piñeyro, Barry Cooper, Robert I. Gregerman,

Cancer, Hypoxia, and Metabolism

Adenylyl cyclase of rat liver and fat cells is activated by chloride, bromide, and iodide in addition to fluoride, previously believed to be uniquely effective among the halide anions. Liver homogenates are activated approximately 6 fold by fluoride while chloride and bromide increase cyclase by 3 fold and iodide about 2 fold. Optimal concentrations of chloride, bromide and iodide are about 100 times higher than those required for activation by fluoride. The cyclase of fat cell ghosts is activated some 9 fold by fluoride, but the other halide anions produced effects very similar in magnitude to those seen with liver, although for fat the optimally effective concentrations were lower. These observations appear to relate adenylate cyclase to a number of other anion activated enzymes, some of which have already been studied in pure form by a number of physico-chemical techniques, and which may serve as models for understanding the action of fluoride and other anions on adenylyl cyclase.