Activation of rat peritoneal mast cells by substance P and mastoparan.

摘要: Incubation of rat peritoneal mast cells with substance P resulted in the transient stimulation phosphoinositol breakdown and histamine secretion through an exocytotic process. These effects were inhibited markedly by a prior 2-hr exposure to pertussis toxin. Pertussis toxin also exocytosis induced P, mastoparan compound 48/80, but did not modify secretory effect ionophore A23187. The transfer from balanced salt solution calcium-free buffer led similar time-dependent decrease their response mastoparan. concomitant absence potassium enabled retain response. data demonstrate identical dependency for calcium monovalent ions process elicited 48/80. Pretreatment neuraminidase decreased secretagogic 48/80 without modifying efficiency Thus, sialic acid residues might be involved initial binding peptides cells, which activate toxin-sensitive G-protein allows increase phospholipase C activity induce exocytosis. This sequence events characterize physiological pathway cell activation peptides, necessarily requiring selective membrane receptors.