Effects of some psychotropic drugs on the osmotic stability and membrane expansion of human erythrocyte membrane

The effect of some psychotropic drugs, CNS stimulants, central bioamines and amino acid neurotransmitters, and their precursors on osmotic stabilization of human rbc was studied by the methods of osmotic shock and hematocrit tube. 1. The tested psychotropic drugs showed high potency against hypotonic rupture of human rbc at 100 Nm-100 mciroM: CPX>PPZ>CZP>CPZ>HPD>PMZ>ATL>DP. The phenothiazines, incontrast to non-phenothiazines,accelerated hypotonic rupture of rbc at 100 microM. Antidepressants were classified into 3 types: 1) hemolysis protector-ALT and DP; 2)hemolysis promoter-CIPM; and 3) non effect on hemolysis-pargyline and lithium carbonate. The potencies were parallel to their psychomotor inhibiting or stimulating effect.The potencies of protection were correlated with the clinical sedative activity, SPR(clinically without sedative effect) was devoid of the protective effect against hemolysis. 2. All tested drugs (10 microM) induced approximately 3%-11% increase of the critical hemolysis relative cell volume(Vr), which was the highest value of the osmotic swelling curve. The concentrations of NaCl corresponding to Vr decreased 25-33 mg/100 mL in the presence of tested psychotropic drugs. The tested drugs did not affect the volume of rbc in 0.5%-0.9% NaCl. The potencies of inducing increased cell membrane expansion of intact rbs were consistent with those against hypotonic rupture. 3. All tested agonists, monoamines and amino acid neurotransmitters, in contrast to the anti-hemolytic effect of antipsychotics, showed promoting effect on hypotonic rupture of rbc with more sensitive response (10 nM- 1pM) and saturation. The potencies of promoting hemolysis by agonists had positive correlation with clinical efficacy of drug for treating minimal brain dysfunction (MBD) in following order: APM>MPD>PML>CF>DN. Among the bioamines and amino acid neurotransmitters only NA,Ala and Gly had strong effects of promoting hemolysis. DA, 5-HT, Glu and Asp had mild effects. The monoamine precursors(Phe,Tyr,L-dopa,Try,and 5-HTP) and other amino acids(GABA,alpha-B,His,Ser,Thr,Val) had no effect on osmotic stabilization of rbc.