ATP-ase activity of mitochondria isolated from needle-biopsy liver samples of diabetic subjects.
ATP-ase activity in mitochondria isolated from liver needle-biopsy samples was measured in 5 diabetics, aged 30-63 years and in 4 control subjects of similar age. The mitochondrial fraction was isolated by differential centrifugation of the homogenate and the ATP-ase activity was determined in the optimal conditions previously described for human liver mitochondria. The basal and Mg-stimulated ATP-ase activities were higher, while the DNP-stimulated ATP-ase activity was lower in diabetics compared to controls. The ratio of DNP-ATP-ase/Mg2+-ATP-ase was between 1-2 in diabetics and above 5 in controls. This pattern of ATP-ase activity in diabetics is indicative of mitochondrial damage. No quantitative changes in the amount of mitochondria isolated from liver (expressed in micrograms mitochondrial protein/mg wet tissue) could be noticed in diabetics compared to controls. Consequently, the alterations of ATP-ase activity is probably reflective of impairments of functional integrity of liver mitochondria in diabetics.
Duţu
A
A
Borza
V
V
Mosora
N
N
Motocu
M
M
Benga
G
G
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000328:Adult; D001707:Biopsy, Needle; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D003920:Diabetes Mellitus / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008930:Mitochondria, Liver / Q000201:enzymology*
D000251:Adenosine Triphosphatases; D017301:Ca(2+) Mg(2+)-ATPase