METABOLISM OF C-14-LABELED SUCROSE ESTERS OF STEARIC-ACID IN RATS

Rats were dosed by oral gavage (250 mg/kg) with compounds containing s ucrose esterified in four, six or eight positions with stearic acid. F or each compound, rats excreted greater than 95% of the dose in the fa eces. The extent of absorption and metabolism of radioactivity was inv ersely related to the degree of esterification. For rats dosed with su crose esters labelled in the fatty acid moieties, the degree of absorp tion of radioactivity was highest for the tetraesterified compound (5. 9% of the dose). At 120 hr after dosing with this derivative, the high est concentrations of radioactivity, aside from tissues of the gastroi ntestinal tract, were found in fat (183 mu g-equivalents/g tissue), ly mph nodes (117 mu g-equivalents/g tissue) and the liver (88 mu g-equiv alents/g tissue); appreciable radioactivity appeared in the blood (3.9 mu g-equivalents/g tissue) and collected lymph (5.0-7.6% of the dose) . For rats dosed with esters labelled in the sucrose moiety, the amoun ts of radioactivity absorbed were lower than after dosing with the cor responding sucrose derivatives labelled in the fatty acid moieties; th e absorbed radioactivity was greatest following administration of the tetraesterified compound (3.0%). Relatively little radioactivity was f ound in tissue samples collected from these rats. These results are co nsistent with limited hydrolysis of the sucrose esters, presumably to sucrose and fatty acids, prior to intestinal absorption. (C) 1997 Else vier Science Ltd.