General Physiology and Biophysics Vol.32, No.1, p.23–32, 2013

Dimethyl sulfoxide (DMSO), a by-product of the pulping industry, is widely used in biological research, cryobiology and medicine.

On cellular level DMSO was shown to suppress NMDA-AMPA channels activation, blocks Na+ channel activation and attenuates Ca2+ influx (Lu and Mattson 2001).

In the present study we explored the whole-cell patch-clamp to examine the acute effect of high concentrations of DMSO (0.1–2 mol/l) on cation channels activity in human erythrocytes.

Acute application of DMSO (0.1–2 mol/l) dissolved in Cl–-containing saline buffer solution significantly inhibited cation conductance in human erythrocytes.

Inhibition was concentration-dependent and had an exponential decay profile.

DMSO (2 mol/l) induced cation inhibition in Cl–- containing saline solutions of: 40.3 ± 3.9% for K+, 35.4 ± 3.1% for Ca2+ and 47.4 ± 1.9% for NMDG+.

Substitution of Cl– with gluconate– increased the inhibitory effect of DMSO on the Na+ current. Inhibitory effect of DMSO was neither due to high permeability of erythrocytes to DMSO nor to an increased tonicity of the bath media since no effect was observed in 2 mol/l glycerol solution. In conclusion, we have shown that high concentrations of DMSO inhibit the non-selective cation channels in human erythrocytes and thus protect the cells against Na+ and Ca2+ overload. Possible mechanisms of DMSO effect on cation conductance are discussed.