EFFECT OF GLYCINE LOADING ON DELTA-AMINOLEVULINIC ACID (ALA) AND PORPHOBILINOGEN (PBG) EXCRETION DURING STARVATION

Studies in 18 nonporphyric subjects demonstrate that starvation from two to 15 days may induce an increase in hepatic ALA synthetase activity, resulting in increasing quantities of urinary ALA excretion which, however, remain within the normal range. The ingestion of glycine during starvation causes a rise above the upper limits of normal in urinary ALA excretion. Starvation does not affect urinary PBG output nor does the ingestion of glycine produce a response. Measurements of ALA dehydrase activity in red blood cells during starvation showed no consistent decrease. Refeeding with a regular diet caused a prompt reduction of urinary ALA excretion and abolished the positive response to glycine. © 1969.