ORGANOPHOSPHORUS INHIBITION OF LYSOSOMAL ENZYME-SECRETION FROM POLYMORPHONUCLEAR LEUKOCYTES - EVIDENCE OF A LACK OF A REQUIREMENT FOR ESTERASE ACTIVATION

Abstract

DFP inhibits the release of lysosomal enzymes induced by chemotactic factors. The inhibition may be due to the phosphorylation of cell bound serine esterase activated by the chemotactic factor. Diisopropyl methyl phosphate, a nonphosphorylating analogue of DFP, inhibits as well as DFP the release of lysozyme and .beta.-glucuronidase from rabbit polymorphonuclear leukocytes [PMN] induced by chemotactic factor in the presence of cytochalasin B. The poorly phosphorylating phenyl ethyl pentylphosphonate and phenyl ethyl phenylpropylphosphonate inhibit enzyme release, induced under the same conditions at least as well as the corresponding good phosphorylators, p-nitrophenyl ehtyl pentylphosphonate and p-nitrophenyl ehtyl phenylpropylphosphonate. Phenyl ethyl pentylphosphonate inhibits at least as well as p-nitrophenyl ethyl pentyl phosphonate the chemotactic factor-induced release of lysozyme from PMN spread on Millipore filters in the absence of cytochalasin B. There is no evidence that the release of lysosomal enzymes from rabbit peritoneal PMN induced by chemotactic factor involves the activation of an esterase.