EFFECT OF DIHYDRALAZINE ON THE FLUIDITY OF ERYTHROCYTE-MEMBRANES

Dihydralazine, a drug used in the treatment of chronic hypertension wa s found to affect the mobility of fatty acid hydrocarbon chains follow ed by spin-labelling technique with the use of 5-, 12- and 16-doxylste arate. The effect of this drug on the membrane bilayer properties may result either from the reduction of the number of double bonds in fatt y acid hydrocarbon chains, as was shown by the changes of d(1)/d and o rder parameters in the region of C-(12) or from direct interactions of the drug with the polar head group region of the phospholipids as was shown by changes in the distance between nitroxyl groups without chan ges of the order parameter in the region of C-(5).