The diverse actions of dimethyl sulphoxide: an indicator of membrane transport activity.

Many membrane-based phenomena depend upon the membrane's ability to regulate the transport of specific cations, principally Na, Ca and Mg. These cations are responsible for a substantial portion of cellular nutrient uptake and the generation/propagation of an action potential. Surfactants, such as carcinogens and some anaesthetics, can disrupt the transport of these cations. Certain highly polar solvents, such as DMSO, can, at times, decrease the effects of carcinogens or some anaesthetics by 'cleansing' the membrane. Yet, on the other hand, they can interact directly with the membrane, producing effects similar to these surfactants. This paper explores membrane transport properties by examining the action of DMSO on normal, malignant and anaesthetized cells. The Brewer membrane model is used as a basis of analysis. It emphasizes the importance of the phospholipid P = O in regulating cation transport through a ground state-excited state cycle. A cleansing-then contaminating surfactant model is proposed to explain the diverse actions of DMSO.