Slow reacting substance (SRS) from ionophore A23187-stimulated peritoneal mast cells of the normal rat. I. Conditions of generation and initial characterization.

When rat peritoneal mast cells were exposed to the ionophore A23187, a principle was released that possessed the biologic properties of slow reacting substance (SRS) from various sources. The response was dose, time, and temperature dependent with no activity being demonstrated in unstimulated cells. Supporting evidence that the mast cell product was similar or identical to SRS obtained from other sources include: 1) appropriate differential bioassay profile, 2) resistance to lipolysis and proteolysis, 3) acid lability and base stability, 4) inactivation by limpet arylsulfatase, and 5) inhibition by low concentrations FPL 55712. These data demonstrate that the isolated rat peritoneal mast cell contains the biosynthetic capacity to produce a bioreactive substance with the properties of SRS.