Effect of L-carnitine administration on the modulated rat brain protein concentration, acetylcholinesterase, Na+K+-ATPase and Mg2+-ATPase activities induced by forced swimming.
BACKGROUND
Forced exercise produces free radicals and L-carnitine (L-C) administration reduces oxidative stress.


OBJECTIVE
To investigate whether short (2 hours) or prolonged (3 hours) forced swimming could modulate total antioxidant status (TAS), protein concentration and activities of acetylcholinesterase (AChE), Na(+)K(+)-ATPase and Mg(2+)-ATPase in rat brain following intraperitonal administration of L-C (300 mg/kg).


METHODS
TAS, protein and enzyme activities were measured spectrophotometrically.


RESULTS
TAS, protein concentration and AChE activity were reduced, whereas Na(+)K(+)-ATPase and Mg(2+)-ATPase were significantly increased after either 2 or 3 hours of training. L-C administration resulted in a profound restoration of TAS and protein concentration whereas AChE and Na(+)K(+)-ATPase were increased before exercise, followed by AChE restoration and Na(+)K(+)-ATPase reduction after exercise. Mg(2+)-ATPase remained unchanged. An in vitro study using L-C incubation of brain homogenates previously treated with L-C resulted in complete restoration of the modulated enzymes, whereas the enzyme activities from untreated animals remained unaltered.


CONCLUSIONS
Short or prolonged swimming in rats may result in a reduction of brain TAS, protein concentration and AChE activity, and an activation of Na(+)K(+)-ATPase and Mg(2+)-ATPase. L-C administration may prevent reduction in TAS and protein concentration, and a decrease in AChE and Na(+)K(+)-ATPase activity; the latter reached pre-exercise values after L-C incubation.
Tsakiris
T
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Department of Experimental Physiology, Medical School, Athens University, PO Box 65257, GR-15401 Athens, Greece. stsakir@cc.uoa.gr
Angelogianni
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Tesseromatis
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Tsakiris
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Schulpis
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D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism*; D002331:Carnitine / Q000494:pharmacology*; D005609:Free Radicals / Q000378:metabolism; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013550:Swimming / Q000502:physiology*
D005609:Free Radicals; D000110:Acetylcholinesterase; D017301:Ca(2+) Mg(2+)-ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D002331:Carnitine