Evaluation of bromosulphtalein clearance in experimental porphyria by isolated and perfused rat liver technique

Porphyria experimentally induced in the rat by oral administration of hexachlorobenzene (HCB porphyria) is characterised by a complex derangement of biliary function, with dysfunction of lipid excretion, that appears unrelated to the extent of porphyrin accumulation in the liver. In this study BSP clearance in rats affected by HCB-porphyria was evaluated by in vitro perfusion of the isolated liver. BSP clearance by medium was normal in the first 20 minutes of perfusion and subsequently was slowed; bile recovery was delayed, and reduced by 60% with respect to control; hepatic BSP storage (calculated as the difference between the BSP dose injected and BSP recovered in bile plus BSP remaining in the medium at the end of each experiment) was approximately double that of control animals. The absence of morphological and biochemical signs of significant liver damage by HCB suggests a competition between porphyrins and BSP at the biliary pole of the hepatocyte.