Abstract
The microsomal Na+-K+-ATPase of rat brain was inhibited by mercury chloride and methyl mercury. The IC50 was 6.5 .times. 10-7 M for mercury chloride and 3.5 .times. 10-6 M for methyl mercury. The inhibition was of a non-competetive type with respect to ATP. The non-ionic detergent Lubrol potentiated the inhibitory effect of both mercurials. It is concluded that Lubrol removes the bulk lipids present outside the catalytic center of the enzyme. Consequently, the enzyme will become more sensitive to the inhibition by both mercurials.