[Comparative characteristics of the distribution and various properties of Na,K-ATPase from human and rat gastric mucosa].
Subcellular fractions were isolated from homogenates of human and rat gastric mucosal membranes by means of differential centrifugation; the highest Na+, K(+)-ATPase activity was detected in microsomal fraction. The enzymatic activity was higher in human gastric mucosal membrane as compared with the rat tissue. Na+, K(+)-ATPase activity was inhibited by 0.1% SDS added into the homogenization mixture. Ouabain 1.5 x 10(-3) M did not affect the enzymatic activity. The enzyme had a pH optimum in both these tissues at pH 7.2 = 7.4 in 30 mM imidazol-HCl buffer and at pH 7.1-7.2 in 40 mM Tris-HCl buffer. K+ exhibited maximal activating effect at 20 mM concentration in human gastric mucosal membrane and at 5 mM concentration in rat tissue. The ratio ATP/Mg2+ as 1:1 proved to be optimal at 2 mM concentration.
Kengsepp
A T
AT
Tiakhepyld
L Ia
LIa
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D005753:Gastric Mucosa / Q000201:enzymology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013045:Species Specificity; D013347:Subcellular Fractions / Q000201:enzymology
D010042:Ouabain; D000255:Adenosine Triphosphate; D000254:Sodium-Potassium-Exchanging ATPase; D008274:Magnesium; D011188:Potassium
Sravnitel'naia kharakteristika raspredeleniia i nekotorykh svoĭstv Na,K-ATPazy slizistoĭ obolochki zheludka cheloveka i krysy.