Sulfatide content and (Na++K+)-ATPase activity of skin and gill during larval development of the chilean frog,Calyptocephalella caudiverbera

Abstract

The sulfatide content, phospholipid concentration, and (Na⁺+K⁺)-ATPase activity from skin and gills of different stages of larval development ofCalyptocephalella caudiverbera (a Chilean frog) were analyzed. Additionally, the short-circuit current in skin was studied. When skin and gills, depending on the stage of larval development, present (Na⁺+K⁺)-ATPase activity, they have a high ratio of sulfatide to amount of membrane and the phosphatidylserine concentration remains unchanged. Sulfatide content and (Na⁺+K⁺)-ATPase activity in skin are in direct relationship with the level of sodium flux present during development. The specific enzymatic hydrolysis of sulfatide with partially purified arylsulfatase of pig kidney inhibits 100% of the ouabain-sensitive (Na⁺+K⁺)-ATPase. The ouabain-insensitive ATPase remains virtually unchanged with the treatment, even with a high concentration of arylsulfatase or with ouabain present in the medium. These experiments strongly suggest a role of sulfatides in the (Na⁺+K⁺)-ATPase activity and, as a consequence, in sodium ion transport.