Masaru Saito

Effects of Lectins on the Hemolysis of Rabbit Erythrocytes by Staphylococcal Alpha Toxin

When concanavalin A (1 μg/ml) or wheat germ agglutinin (2 μg/ml) was preincubated with a suspension of 2% rabbit erythrocytes for 5 min at 20 C, the binding of [125I]‐labeled staphylococcal alpha toxin to these erythrocytes was greatly inhibited and the hemolytic action of alpha toxin was decreased. The inhibitory effect of concanavalin A on hemolysis by alpha toxin was completely reversed in the presence of 0.1 M α‐methyl‐D‐glucoside or α‐methyl‐D‐mannoside. Phytohemagglutinin‐P from Phaseolus vulgaris and soybean agglutinin inhibited hemolysis by the toxin at concentrations exceeding 20 μg/ml.

Studies on the synthesis of cholecystokinin A receptor antagonists. IV. Synthesis and cholecystokinin A receptor inhibitory activities of benzimidazole derivatives

A number of benzimidazole derivatives were synthesized and tested for cholecystokinin A (CCK-A) receptor inhibitory activity in order to study structure-activity relationships. Significant CCK-A receptor inhibitory activities were found in the compounds having carboxyl or tetrazolyl group. As the most preferred compound, 4-(5,6-dichlorobenzimidazol-2-yl)-N-(3-methoxypropyl)-N-pentylg lutaramic acid (4g) was selected.