title: Ca²⁺ ions regulate activity of Na⁺ ,Cl⁻(HCO₃ ⁻)-ATPase in the mucosa of rabbit small intestine.
abstract: We studied the effects of bivalent metal ions on activity of Na(+),Cl(-)(HCO3 (-))-ATPase was studied. In contrast to Ba(2+), Co(2+), Zn(2+), and Mn(2+) ions, Ca(2+) and Mg(2+) ions in a concentration of 0.25 mM completely inhibited this enzyme. Histamine in vivo significantly decreased the inhibiting effect of Ca(2+) on Na(+),Cl(-)(HCO3 (-))-ATPase. A possible mechanism of regulation of enzyme activity by Ca(2+) ions and its possible relation with CFTR protein providing permeability of enterocyte apical membrane for Cl(-) ions was proposed.
authors.affiliation: Laboratory of Molecular Mechanisms for Infections, Central Research Institute of Epidemiology, Moscow, Russia.
authors.forename: V A
authors.initials: VA
authors.lastname: Yurkiv
authors.forename: V I
authors.initials: VI
authors.lastname: Melikhov
authors.forename: V S
authors.initials: VS
authors.lastname: Shubin
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism*; D011817:Rabbits; D012964:Sodium / Q000378:metabolism*
chemical_list: D002712:Chlorides; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D012964:Sodium; D000251:Adenosine Triphosphatases; D002118:Calcium