Release of Slow Reacting Substance (SRS) from Rat Basophilic Leukemia (RBL-1) Cells

摘要: When rat basophilic leukemia (RBL-1) cells were exposed to the ionophore A23187, a substance was released that produced prolonged contraction of guinea pig ileum resembling seen with slow reacting substances (SRSs) from various sources. The response temperature, dose, and time dependent no activity being demonstrated in unstimulated cells. Several lines evidence indicated RBL-1 product markedly similar or identical SRSs obtained non-neoplastic tissues: 1) appropriate behavior seven different chromatographic systems, 2) an profile on smooth muscle preparations, 3) ability low concentrations selective SRS inhibitor FPL 55712 block ileal response, 4) failure chymotrypsin destroy activity, 5) loss after incubation arylsulfatase, 6) release preincubated indomethacin. Since can be grown considerable quantity under optimal conditions average 1500 units/10 7 obtained, these should useful as biosynthetic source further attempts purify characterize molecule.