Effects of some S-alkylthiouroniums and related compounds on the osmotic fragility and the membrane expansion of human erythrocytes.
1 Changes in the osmotic fragility and critical haemolytic volume of human erythrocytes produced by S-n-decylthiouronium (S-10) and related compounds have been studied. 2 S-10 had a biphasic action on osmotic fragility, protecting erythrocytes against lysis in low concentrations but producing lysis in a concentration of 1 mM or higher. 3 Some lower homologues of S-10 also protected erythrocytes against osmotic lysis, the degree of protection depending on the length of the alkyl chain. 4 Critical haemolytic volume was increased by antihaemolytic concentrations of procaine and chlorpromazine but not by antihaemolytic concentrations of S-10 and related amidines. 5 It is concluded that S-10 and its near homologues penetrate and stabilize erythrocyte membranes, potency increasing with the number of methylene groups in the side-chain up to about ten. The stabilization produced by S-10 apparently differs from that produced by many other lipid-soluble depressant drugs. It may be related to a drug-induced change in the ionic permeability of the membrane.
D002746:Chlorpromazine / Q000494:pharmacology; D004910:Erythrocyte Membrane / Q000187:drug effects*; D004912:Erythrocytes / Q000187:drug effects*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D009996:Osmotic Fragility / Q000187:drug effects*; D011343:Procaine / Q000494:pharmacology; D013890:Thiourea / Q000494:pharmacology*
D011343:Procaine; D013890:Thiourea; D002746:Chlorpromazine