Abstract
1. Homopantothenic acid (HOPA) and Pantothenic acid (PaA), intraperitoneally injected in the rat, were taken up by the central nervous system. There was no marked difference in regional distribution of HOPA in the brain. The concentration of HOPA in the various regions of the brain was almost unchanged by treatment with 2-methyl-4-amino-5-hydroxymethylpyrimidine. 2. Studies on the uptake of HOPA and γ-aminobutyric acid (GABA) by rat brain slices revealed that GABA was actively transported, whereas HOPA was passively transported. 3. The major portion of HOPA orally administered in the rat was excreted in the urine within 24 hours. More than 95% of the excreted substance was HOPA and the remaining less than 5% remained unknown.
