BUTYROBETAINE IS EQUAL TO L-CARNITINE IN ELEVATING L-CARNITINE LEVELS IN RATS

This work shows that butyrobetaine administered to rats in a single dose can be highly effective in elevating L-carnitine levels in all tissues. This ability of butyrobetaine was compared to that of L-carnitine. In an experiment with tracer dose of the compounds, 12 h following administration of [H-3]butyrobetaine plasma and tissues contained radioactivity exclusively in L-carnitine and in similar amounts as in the other group of animals receiving L-[H-3]carnitine. This was observed both after intraperitoneal and oral administration of the compounds. In the loading experiments 100-mu-mol [H-3]butyrobetaine was administered orally to one group and 100-mu-mol L-[H-3]carnitine to the other group of animals and 12 h later it was found that butyrobetaine caused the same increments in L-carnitine as L-carnitine administration. The increments in the organs of the butyrobetaine-treated group (in decreasing order) were as follows: kidney, 1227 nmol/g vs. 652 nmol/g; liver, 469 nmol/g vs. 258 nmol/g; muscle, 1043 nmol/g vs. 881 nmol/g; plasma, 79.4 nmol/ml vs. 39.3 nmol/ml. Butyrobetaine (100-mu-mol) caused similar increments when it was administered intraperitoneally. Based on these results butyrobetaine can be considered as a potential agent for L-carnitine supplementation therapy.