SELECTIVE TROPHIC EFFECT OF L-CARNITINE IN TYPE-I AND IIA SKELETAL-MUSCLE FIBERS

Biopsies were taken from the vastus lateralis muscle of 26 chronic ure mic patients before and after a 24-week treatment with L-carnitine giv en at the dose of 2 g i.v. at the end of hemodialysis, or in dialysis solution, or per os twice daily. The aim of the study was to evaluate bath the muscle morphology in dialyzed subjects and the modification p rovoked by the therapy. All patients manifested a significant, even if variable, degree of muscular atrophy which involved all types of musc le fibers. After the treatment there was an increase of about 7% in th e diameter of type I and type IIa fibers, which can utilize carnitine for fatty acid oxidation to produce energy, and a reduction in the atr ophic fibers. No noteworthy changes were documented in type IIb, fiber s, which depend on glycolysis for energy production.