acid-phosphatase and 4-bromophenacyl-bromide

The effect of phospholipase A2 (PLA2) inhibitor, quinacrine, on the activity of hydrolytic enzymes in Tetrahymena pyriformis homogenate, was investigated. The activity of all of the enzymes studied (acid phosphatase, N-acetyl-beta-glusosaminidase, glucosidase, galactosidase and esterase) was significantly reduced in the presence of quinacrine. Since there are no data on the inhibitory effect of PLA2 and PLA2 influenced metabolic pathways to the hydrolytic enzymes, the direct effect of quinacrine on the hydrolytic enzymes (of Tetrahymena) can be supposed. This is supported by the fact that the other PLA2 inhibitor, 4-bromophenacyl bromide, did not influence phosphatase activity.

Topics: Acetophenones; Acetylglucosaminidase; Acid Phosphatase; Animals; Antimalarials; Cell Fractionation; Enzyme Inhibitors; Esterases; Galactosidases; Glucosidases; Hydrolases; Quinacrine; Tetrahymena pyriformis

Two active site inhibitors of acid proteinases were tested for their effects on human neutrophil chemotaxis and lysosomal enzyme release. Both bromphenacyl bromide (BPAB) and epoxy-p-nitrophenoxypropane (EPNP) inhibited chemotaxis and chemotaxin-induced enzyme release elicited by pepstatin and formylmethionyl peptides, which share membrane receptors, and also by zymosan-activated serum, the major active component of which (C5a) occupies a different receptor. In contrast to the previously tested acid protease inhibitor diazoacetylnorleucine methyl ester, neither BPAB nor EPNP blocked binding of [3H]fMLP to neutrophils. Thus BPAB and EPNP inhibit chemotaxin-mediated neutrophil functions, but not by interaction with the chemotaxin receptor.

Topics: Acetophenones; Acid Phosphatase; Chemotaxis, Leukocyte; Dipeptides; Epoxy Compounds; Humans; Lysosomes; Muramidase; N-Formylmethionine; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils; Nitrophenols; Oligopeptides; Pepstatins; Protease Inhibitors