In- Vitro Hepatotoxicity of Three Dichlorobenzene Isomers in Human Liver Slices

Abstract

1 The cytotoxicity of dichlorobenzenes in cultured rat liver slices has previously been shown to be strain specific and biotransformation related.

2 In order to extrapolate animal models to humans, the dichlorobenzenes were incubated with human liver slices to try to clarify their hepatotoxic potential in man.

3 The degree of hepatotoxicity observed with the dichlorobenzenes depended on whether Waymouth's or Krebs-Henseleit was used as the incubation medium.

4 All three dichlorobenzenes (1 mM) produced no significant differences from control when incubated in Waymouth's medium. However, in the Krebs-Henseleit buffer there was a substantial increase in cytotoxicity.

5 In both incubation mediums the dichlorobenzene isomers exhibited the following rank order 1,3-DCB > 1,2-DCB > 1,4-DCB.

6 1,2-dichlorobenzene hepatotoxicity was blocked by metyrapone, 1,3-dichlorobenzene toxicity was blocked by SKF 525-A and neither one of these inhibitors could block the 1,4-dichlorobenzene cytotoxicity.

7 The use of human liver tissues to evaluate potential toxicants merits consideration since the hepatotoxicity of xenobiotics and drugs in man is the ultimate question.