Biliary excretion of [C]succinylsulphathiazole in the rat and rabbit

A study on the fate of curcumin in the rat

The uptake, distribution and excretion of curcumin in Sprague-Dawley rats has been studied. When administered orally in a dose of 1 g/kg, curcumin was excreted in the faeces to about 75%, while negligible amounts of curcumin appeared in the urine. Measurements of blood plasma levels and biliary excretion showed that curcumin was poorly absorbed from the gut. No apparent toxic effects were seen after doses of up to 5 g/kg. When intravenously injected or when added to the perfusate of the isolated liver, curcumin was actively transported into bile, against concentration gradients of several hundred times. The major part of the drug was however metabolized. In suspensions of isolated hepatocytes or liver microsomes 90% of the added curcumin was metabolized within 30 min. In view of the poor absorption, rapid metabolism and excretion of curcumin, it is unlikely that substantial concentrations of curcumin occur in the body after ingestion.

Effect of nafenopin (SU-13,437) on liver function: influence on the hepatic transport of organic anions

Rats treated with hypolipidemic agent, nafenopin (SU-13, 437) exhibit a higher plasma retention and a markedly reduced biliary excretion of organic anions, such as sulfobromophthalein (BSP) and its dibromo analog (DPSP), indocyaninegreen (ICG), succinylsulfathiazole (SST) and polar metabolites of bilirubin and the carcinogens 7, 12-dimethylbenzanthracene (DMBA) and 3,4 benzpyrene (BP), despite an increase in liver mass and a profound choleresis. However, taurocholate is not affected in this manner, which supports the idea of a transport mechanism for taurocholate that differs from that of other organic anions. A pharmacokinetic study was made for DBSP in vivo. After nafenopin treatment, primary hepatic uptake (k12) and transport from liver into bile (k23) are reduced in vivo. Infusion studies indicate that biliary transport maximum (Tm) for DBSP is also decreased although the calculated hepatic storage (S) is only moderately affected. In the isolated perfused liver, hepatic clearance and biliary excretion of BSP are reduced by two-thirds. The time course of anion transport inhibition and the hepato-biliary disposition of 14C-nafenopin suggest a direct effect of the drug. The extra liver mass induced by nafenopin appears to be hypo- or nonfunctional with respect to hepatic transport of organic anions.

Steroid metabolism in the cat. Biliary and urinary excretion of metabolites of [4-14C]cortisone

1. [4-(14)C]Cortisone was administered to anaesthetized male cats as a single injection or as a 45-60min. infusion. 2. After the single dose a total of 69.6-89.6% of the radioactivity was excreted in bile, and 0.5-7.1% in urine. After infusion total recovery in bile was 73.4-92.1%, and 1.2-1.7% in urine. 3. When bile and urine samples were hydrolysed successively by beta-glucuronidase, cold acid and hot acid, most of the radioactivity was converted into substances not extractable from neutral aqueous solution by ethyl acetate-ether. 4. In bile, metabolites hydrolysable by beta-glucuronidase were found in only small proportions (3-4%) of the dose.