Effect of acetyl-L-carnitine on conditioned reflex learning rate and retention in laboratory animals.

The aim of the study was to evaluate the effects of acetyl-L-carnitine on learning and/or memory processes in laboratory animals. In the water maze test, acetyl-L-carnitine, given intraperitoneally at doses ranging from 0.3 to 100 mg/kg, improved performances in both mice and rats. In the latter the drug also proved active when administered orally in the 3-100 mg/kg dosage range. In the pole climbing test in the rat, acetyl-L-carnitine at doses ranging from 0.03 to 10 mg/kg i.p. increased the conditioned reflex learning rate. In the passive avoidance test in the rat, significant increases in retention were observed after treatment with acetyl-L-carnitine at doses ranging from 1 to 30 mg/kg i.p. In the passive avoidance plus electroconvulsive shock test in the mouse, acetyl-L-carnitine antagonized amnesia at doses ranging from 0.1 to 3 mg/kg i.p.