EFFECTS OF BIOGENIC-AMINES AND GLUCAGON ON THE ADENYLATE-CYCLASE SYSTEM IN MOLLUSCAN, HOLOTHURIAN AND ASCIDIAN MUSCLE MEMBRANES

The in vitro effects of biogenic amines and glucagon on the adenylate cyclase activity of muscle membranes of molluscs (Tonicella marmorea, Mytilus edulis, Mizuhopecten yessoensis, Spisula sachalinesis, Littori na littorea, Lymnaea stagnalis, Planorbarius corneus), holothurian (Cu cumaria japonica) and ascidian (Halocyntia aurantium) were studied, Gl ucagon, beta-adrenergic agonists and serotonin have a stimulating effe ct on the sarcolemmal adenylate cyclase activity potentiated by guanin e nucleotides. The serotonin antagonist, cyproheptadine, and beta-anta gonists blocked the effect of hormones, Serotonin receptor (5-HTR) and beta-adrenoreceptor (beta-AR) in the sarcolemma of Anodonta cygnea, M izuhopecten yessoensis, Spisula sachalinesis, Cacumaria japonica and H alocyntia aurantium were identified, A negative regulation of 5-HTR an d beta-AR affinity by guanine nucleotides was revealed, which provides evidence of the functional coupling of the receptors with GTP-binding protein, The results of the comparative study of the hormone-sensitiv e adenylate cyclase system suggest a certain similarity in the structu ral and functional organization of the system in invertebrates and ver tebrates.