Changes in phospholipid constituents in mitochondrial membranes after long lasting exercise in rat heart.
Phosphatidylethanolamine, phosphatidylcholine and cholesterol were found to be significantly decreased to 44, 56 and 54% of the control values (p less than 0.001, 0.05 and 0.05, respectively), in cardiac mitochondria from rats which were made to swim bearing a weight representing 3% of body weight for 3 or more hours in water at 35 degrees C. The ratio of cholesterol to phospholipid did not change. Membrane viscosity tended to decrease very slightly. Steady-state anisotropy at infinite time, fluorescence life time and wobbling angle of phospholipids showed no significant change. Electron-microscopy showed no clear morphological damage, swelling or hypertrophy of cardiac mitochondria after long lasting exercise. The number of mitochondria was found to be increased by 19% in the long lasting exercise group compared with the control group. It was noteworthy that the dynamic microstructure and electron-microscopic structure of the cardiac mitochondria remained unaltered despite the remarkable changes in the phospholipid constituents.
Keatisuwan
W
W
Section of Physiology, Hokkaido University, Sapporo, Japan.
Kinjo
M
M
Koyama
T
T
D000818:Animals; D002784:Cholesterol / Q000378:metabolism*; D005454:Fluorescence Polarization; D007425:Intracellular Membranes / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D008929:Mitochondria, Heart / Q000378:metabolism* / Q000648:ultrastructure; D010713:Phosphatidylcholines / Q000378:metabolism*; D010714:Phosphatidylethanolamines / Q000378:metabolism*; D005082:Physical Exertion; D051381:Rats; D011919:Rats, Inbred Strains; D014783:Viscosity
D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D002784:Cholesterol