Use of SDS and saponin detergents for the demonstration and purification of (Na+K+)ATPase in sheep kidney]

Incubation of membrane fragments from sheep kidney outer medulla in detergents such as SDS or saponin revealed increased specific (NA+) ATPase activity. Measurement of enzyme phosphorylation from [gamma 32P] ATP showed irreversible alteration of EP to (Na+) ATPase activity ratio when SDS is used as unmasking agent. These results were found with unmasked and purified enzyme.