Effect of cetiedil on erythrocyte sickling: new type of antisickling agent that may affect erythrocyte membranes.

The antisickling effect of cetiedil, alpha-cyclohexyl-3-thiopheneacetic acid 2-(hexahydro-1H-azepin-1-yl)-ethyl ester, has been investigated. The concentration of cetiedil required for 50% inhibition of erythrocyte sickling was about 140 micro M. An antisickling effect was achieved regardless of whether cetiedil was added before or after deoxygenation. The minimal gelling concentration of deoxy Hb S was increased by less than 10% in the presence of 218 micro M cetiedil. The oxygen equilibrium curves of Hb S were not significantly affected by cetiedil. Erythrocytes treated with high concentrations of cetiedil were swollen and became spheroidal. The antisickling effects of cetiedil might be due to an effect on erythrocyte membranes.