Time course of dolichol and dolichyl phosphate in regenerating rat liver

By using novel high performance liquid chromatographic methods, the time course of dolichol and dolichyl phosphate in regenerating rat liver was investigated and compared with that for cholesterol. The cholesterol level in the liver increased more rapidly than the level of dolichyl phosphate (Dol-P). HMG-CoA reductase activity correlated well with cholesterol concentration. The level of Dol-P at day 1 was lower than that in normal liver, but was increased at three to five days after hepatectomy, which correlates well with mannosyl transferase activity. Dolichol decreased for three days, and thereafter increased until 11 days after hepatectomy. The compositions of dolichol and Dol-P homologues did not change during the experimental period. The results indicate that the cholesterol content in regenerating rat liver increased first, followed by Dol-P, and finally dolichol.