Keimei Hosokawa

Tissue Plasminogen Activator in the Pathogenesis of Protein-Losing Gastroenteropathy

Tissue fibrinolytic activity, mainly due to activator of tissue plasminogen was increased in the biopsied gastric mucosa of patients with protein-losing gastropathy. Antiplasmin therapy with trans-AMCHA (trans-4-aminomethyl cyclohexane carboxylic acid) was dramatically effective, except in the case of a patient with intestinal lymphangiectasia. These findings suggest that increased fibrinolysis in the gastrointestinal mucosa may play an important role in enhancing mucosal permeability to plasma proteins.

Lipid peroxidation and lysosomal enzymes in D-galactosamine hepatitis and its protection by vitamin E

SummaryRole of Iipid peroxidation on lysosomal instability in liver tissue was investigated in an experimental model of D-galactosamine hepatitis in rats fed on vitamin E (V.E) deficient diet.Administration of D-galactisamine to V.E deficient rats resulted in a sudden increase of serum glutamic oxaloacetic transaminase (sGOT), glutamic pyruvic transaminase (sGPT), lipid peroxide value, as well asβ glucuronidase and acid phosphatase activity examined as markers of lysosomal enzymes, when compared with control rats fed on V.E supplemented diet.Lipid peroxide in the liver tissue also showed significant increase in V.E deficient rats. In contrast, \- glucuronidase and acid phosphatase in the liver tissue were found to decrease in V.E deficient rats by the administration of D-galactosamine, indicating that the enzymes in the lysosome were entirely released outside the liver cells as a result of cell destruction.It is concluded that the increase of lipid peroxide causes the instability of lysosomal membranes and releases various kinds of hydrolytic enzymes to lead further cell damage. V.E might act on inhibiting lipid peroxidation to stabilize lysosomal membranes.

Induction of Heinz Body Formation by Sodium Dithionite

Incubation of normal erythrocytes with sodium dithionite resulted in the formation of Heinz bodies, but incubation with sodium metabisulfite did not. Addition f superoxide dismutase to the incubation medium increased the formation of Heinz bodies by sodium dithionite. Addition of catalase to suspensions of erythrocytes in the presence and absence of superoxide dismutase inhibited the formation of Heinz bodies. These findings indicate that hydrogen peroxide, not superoxide, is the active oxidant in Heinz body formation.