A method for the estimation of glucose-1-phosphate and galactose-1-phosphate in the liver

Abstract

Glucose-1-phosphate and galactose-1-phosphate are detd. in trichloroacetic acid extracts of rats'' livers. After removal of interfering reducing substances, i.e., nitrogenous phosphoric esters, bile pigments, and glycogen, by means of mercuric acetate and HgS, the organic phosphates are separated from inorganic P as water-soluble Ba salts. The reducing power of the organic phosphate fraction gives an approx. measure of the amount of hexose-6-phosphates present. The quantity of glucose-1-phosphate and galactose-1-phosphate taken together is detd. by the increase in reducing power and the amt. of inorganic P liberated after hydrolysis in a mixture of 0.05 N HC1 and 3.2 N H2SO4 at 100[degree] for 3 min. Incubation with 0.25 N acid it 50[degree] for 30 min. hydrolyses 28.6% of glucose-1-phosphate and 77.5% of galactose-1-phosphate. In a mixture of the 2 esters, the ratio 50[degree] value/100" value is detd. by the elative concs. of the esters.