Physiological screening for target site insensitivity and localization of Na+/K+-ATPase in cardenolide-adapted Lepidoptera

► Arctiids storing high cardenolide amounts possess ouabain sensitive Na+/K+-ATPases. ► Na+/K+-ATPase in the species tested appears to be restricted to the nervous tissue. ► Arctiid larvae possess high cardenolide concentrations in the haemolymph.