title: The in vivo and in vitro effects of L-carnitine supplementation on the erythrocyte membrane acetylcholinesterase, Na+, K+-ATPase and Mg2+-ATPase activities in basketball players.
abstract: BACKGROUND
  We investigated whether the activities of erythrocyte membrane acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase are modulated in basketball players pre- vs. post-forced training with or without L-carnitine (L-C) supplementation.
  
  
  METHODS
  Blood was obtained from 10 male players pre-game (group A) and post-game (group B) and after 1 month L-C supplementation (2 g/24 h orally) pre-training (group C) and post-training (group D). Lactate, pyruvate and total antioxidant status (TAS) were measured with commercial kits, catecholamines with HPLC and the enzyme activities spectrophotometrically.
  
  
  RESULTS
  Lactate, pyruvate, AChE, Na+, K+-ATPase and catecholamines were increased (p<0.001) and TAS was decreased (p<0.001) in group B. In contrast, TAS remained unaltered and the all enzyme activities were reduced (p<0.001) in group D at the same time of study. Mg2+-ATPase activity remained unchanged. In vitro incubation of the modulated AChE and Na+, K+-ATPase with L-C (25 microM) from group B and group D resulted in a non-significant reduction of the enzymes in group B and complete restoration of their activities in group D.
  
  
  CONCLUSIONS
  The increase of AChE and Na+, K+-ATPase activities may be due to the elevation of catecholamines in group B. Carnitine utilization by the muscles during training may result in a reduction of the enzyme activities (group D). The latter is supported by the recovery of the enzyme activities after incubation of the membranes from group D with L-C.
authors.affiliation: Department of Experimental Physiology, Medical School, University of Athens, and Institute of Child Health, Research Center, Aghia Sophia Children's Hospital, Athens, Greece.
authors.forename: Theodore
authors.initials: T
authors.lastname: Parthimos
authors.forename: Kleopatra H
authors.initials: KH
authors.lastname: Schulpis
authors.forename: Panagoula
authors.initials: P
authors.lastname: Angelogianni
authors.forename: Christi
authors.initials: C
authors.lastname: Tsopanakis
authors.forename: Nickolaos
authors.initials: N
authors.lastname: Parthimos
authors.forename: Stylianos
authors.initials: S
authors.lastname: Tsakiris
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood*; D000975:Antioxidants / Q000032:analysis / Q000378:metabolism; D001490:Basketball; D017301:Ca(2+) Mg(2+)-ATPase / Q000097:blood*; D002331:Carnitine / Q000494:pharmacology*; D002395:Catecholamines / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements; D004789:Enzyme Activation; D004910:Erythrocyte Membrane / Q000201:enzymology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009132:Muscles / Q000378:metabolism; D019289:Pyruvic Acid / Q000097:blood; D000254:Sodium-Potassium-Exchanging ATPase / Q000097:blood*; D013057:Spectrum Analysis; D013997:Time Factors
chemical_list: D000975:Antioxidants; D002395:Catecholamines; D019344:Lactic Acid; D019289:Pyruvic Acid; D000110:Acetylcholinesterase; D017301:Ca(2+) Mg(2+)-ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D002331:Carnitine