because na+ , k+-atpase activity is fluidity dependent and the physiochemical properties of the apical membrane reduces its fluidity , we investigated whether altering membrane fluidity might uncover cryptic na+ , k+-atpase in bile canalicular ( apical ) surface fractions free of detectable na+ , k+-atpase and glucagon-stimulated adenylate cyclase activities .
C0001473
apical
C0001479
na