alpha-chymotrypsin and phenylhydrazine

Phenylhydrazine was shown to reduce the content of erythroblast islands (EI) within 24 hrs in the rat bone marrow, the effect depending on the dose. Simultaneous strengthening of phagocytic activity, acidifying of lysosomes central macrophages EI and lowering of electrophoretic mobility, were observed. The proteinase inhibitor contrycal (50 and 500 i. u.) prevented the effect in the EI and intensified the regeneration of erythron. In vitro, trypsin and chymotrypsin decreased the EI content in the marrow cell suspension. Changing of functional condition of the central macrophages EI and, probably, products of its secretion, seems to affect the cell complementing in EI.

Topics: Animals; Aprotinin; Bone Marrow; Bone Marrow Cells; Chymotrypsin; Dose-Response Relationship, Drug; Electrophoresis; Erythroblasts; Erythropoiesis; Hydrogen-Ion Concentration; Lysosomes; Male; Phenylhydrazines; Rats; Time Factors; Trypsin

Membrane phospholipid and protein organization was studied in intact human erythrocytes exposed to phenylhydrazine, an oxidative agent inducer. The evaluation of the membrane phospholipid and protein organization was carried out in terms of asymmetric distribution across the membrane bilayer for the phospholipids, and in terms of accessibility of cleavable sites present on the outer membrane surface for the proteins. Treatment of phenylhydrazine-exposed erythrocytes either with bee venom phospholipase A2 or with trinitrobenzenesulfonic acid indicated that phosphatidylserine (PS), which is the only phospholipid not formally present on the outer leaflet of the membrane, was translocated to the outer surface of the cell membrane. The extent of this phenomenon was directly proportional to the concentration of the oxidant having a peak value at 0.1 mM. Phosphatidylcholine and phosphatidylethanolamine conserved their original distribution across the erythrocyte membrane throughout the study. The oxidant, at a dose which did not induce any modification of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis cytoskeleton membrane protein pattern, did not provoke any alteration of the membrane protein surface architecture, although the translocation of PS to the membrane outer leaflet in intact erythrocytes was present.

Topics: Analysis of Variance; Blood Proteins; Chymotrypsin; Dose-Response Relationship, Drug; Electrophoresis, Polyacrylamide Gel; Erythrocyte Membrane; Humans; Lipid Bilayers; Membrane Lipids; Membrane Proteins; Oxidation-Reduction; Phenylhydrazines; Phosphatidylserines; Phospholipases A; Phospholipases A2; Phospholipids; Spectrin