title: The differential release of basal ATPase, Ca2+-dependent ATPase, 5'-nucleotidase and cholesterol during homogenization of skeletal muscle.
abstract: The influence of homogenization times on the presence of constituents in the microsomal fraction of skeletal muscle was investigated. Membranes having Ca2+-activated ATPase activity have a fragmentation pattern distinct from that of membranes displaying Ca2+-independent or basal ATPase activity. These latter membranes were found in highest specific concentration in the microsomal fraction prepared from homogenates subjected to short periods of homogenization. 5'-Nucleotidase (EC 3.1.3.5) activity paralleled that of basal ATPase on short periods of homogenization, as also did the specific concentration of cholesterol. Longer periods of homogenization led to a decrease in the specific activity of basal atpase, which reached its lowest value at 120s of homogenization, whereas the specific activity of 5'-nucleotidase and the specific concentration of cholesterol decreased initially in a similar manner to basal ATPase, but both increased substantially after the longest period of homogenization.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D002458:Cell Fractionation; D002784:Cholesterol / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D008861:Microsomes / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D009708:Nucleotidases / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D013997:Time Factors
chemical_list: D009124:Muscle Proteins; D010743:Phospholipids; D002784:Cholesterol; D009708:Nucleotidases; D000251:Adenosine Triphosphatases