Heterogeneous expression of sulphotransferases in periportal and perivenous hepatocytes prepared from male and female rat liver.

Sulphotransferase (ST) is a family of enzymes responsible for metabolism and detoxication of endobiotics and xenobiotics. We investigated the hepatic acinar distribution of three sulphotransferases: phenol sulphotransferase (PST), oestrogen sulphotransferase (EST), and hydroxysteroid sulphotransferase (HST) in male and female rat livers by measurement of enzyme activities in isolated periportal and perivenous hepatocytes. The distribution was confirmed by immunohistochemistry. EST activity was located predominantly in the perivenous hepatocytes in male rats but not in female rats, where residual activity is catalysed by another ST. HST activity was not significantly different in periportal and perivenous hepatocytes in either male or female rats. For PST, a more widespread distribution was observed, with slight predominance in the periportal regions. The results indicate heterogeneous distribution of ST isoenzymes in the periportal and perivenous hepatocytes isolated from male and female rat livers.