title: Ouabain-insensitive, Na(+)-stimulated ATPase activity in rabbit cardiac sarcolemma.
abstract: The rabbit cardiac sarcolemma shows an ouabain, Na,K-stimulated ATPase activity and an ouabain-insensitive, Na-stimulated ATPase activity. The Na-ATPase has the following characteristics: (i) It is also stimulated by other monovalent cations. (ii) It is inhibited by 2 mM Furosemide and by 2 mM ethacrynic acid. (iii) It reaches maximal values (Vmax) at around 20 mM Na+. (iv) The apparent Km is around 5 mM. Except for the monovalent cation stimulation, the main characteristics of this ATPase are very similar to those of the ouabain-insensitive, Na-stimulated ATPase of mammalian kidneys.
authors.affiliation: Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas.
authors.forename: J L
authors.initials: JL
authors.lastname: Camejo
authors.forename: T
authors.initials: T
authors.lastname: Proverbio
authors.forename: F
authors.initials: F
authors.lastname: Proverbio
mesh_terms: D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000818:Animals; D027682:Cation Transport Proteins; D002412:Cations / Q000494:pharmacology; D004976:Ethacrynic Acid / Q000494:pharmacology; D005665:Furosemide / Q000494:pharmacology; D007700:Kinetics; D009206:Myocardium / Q000201:enzymology*; D010042:Ouabain / Q000494:pharmacology*; D011817:Rabbits / Q000378:metabolism*; D012508:Sarcolemma / Q000201:enzymology*; D012964:Sodium / Q000494:pharmacology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors; D013268:Stimulation, Chemical
chemical_list: D027682:Cation Transport Proteins; D002412:Cations; D010042:Ouabain; D005665:Furosemide; D012964:Sodium; D000251:Adenosine Triphosphatases; C021838:sodium-translocating ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D004976:Ethacrynic Acid