title: [The distribution and properties of the Mg2(+)-ATPase in the membranes of functionally different muscles in the hen].
abstract: From striated (m. pectoralis and myocardium) and smooth (myometrium) muscle tissues of hen, by means of differential centrifugation with Ca-oxalate loading, membrane preparations were obtained with high activity of Mg(2+)-ATPase, i.e. a marker enzyme of tubular membranes of T-system of skeletal muscles. Some properties (pH and temperature optima) of this enzyme were investigated and compared to those of Ca(2+)-ATPase from membranes of the sarcoplasmic reticulum. It was shown that in all the investigated muscles, Mg(2+)-ATPase is associated with membrane fraction which in its density corresponds to tubular membranes of T-system. Activation of this enzyme is characterized by similar optimal levels of pH (7.2) and temperature (25 degrees C). The activity of Ca(2+)-ATPase in the membranes of the sarcoplasmic reticulum, in contrast to that of Mg(2+)-ATPase, is observed in more narrow bands of pH and temperature, exhibiting tissue specificity. The data obtained, indicating a possibility of chromatographic separation of these enzymes, confirm their biochemical individuality.
authors.forename: M V
authors.initials: MV
authors.lastname: Mikhaĭlova
authors.forename: N B
authors.initials: NB
authors.lastname: Gontareva
authors.forename: V P
authors.initials: VP
authors.lastname: Nesterov
mesh_terms: D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000032:analysis / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000032:analysis / Q000378:metabolism; D002645:Chickens / Q000378:metabolism*; D005260:Female; D006863:Hydrogen-Ion Concentration; D007425:Intracellular Membranes / Q000737:chemistry / Q000201:enzymology*; D008861:Microsomes / Q000737:chemistry / Q000201:enzymology; D009130:Muscle, Smooth / Q000737:chemistry / Q000201:enzymology; D009132:Muscles / Q000737:chemistry / Q000201:enzymology*; D009206:Myocardium / Q000737:chemistry / Q000201:enzymology; D013696:Temperature
chemical_list: D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases
vernacular_title: Raspredelenie i svoĭstva Mg2(+)-ATFazy v membranakh funktsional'no razlichnykh myshts kury.