Age- and sex-related changes in amine sulphoconjugations in Sprague-Dawley strain rats. Comparison with phenol and alcohol sulphoconjugations

Abstract

1. Age- and sex-related changes in sulphoconjugation were investigated in hepatic 105 000g supernatants of three-week-old (young), seven-week-old (young adult), one-year-old (middle-aged) and two-year-old (old) Sprague-Dawley rats in the presence of biologically active sulphate. 2. The supernatants of seven-week-old, one-year-old and two-year-old female rats catalysed the sulphoconjugations of alcohol (tiaramide as substrate), and alicyclic amine, alkylamine and arylamine more rapidly than those of the respective males, but the supernatants of three-week-old rats did not exhibit significant sex-related differences. The sulphoconjugations by the supernatants of female rats were substantially constant during ageing. 3. On the other hand, the supernatants of seven-week-old male rats catalysed phenol (β-naphthol as substrate) sulphoconjugation more rapidly than those of seven-week-old females, but the supernatants of two-year-old rats did not exhibit this sex-related difference. 4. These results indicate that the substrates for sulphoconjugation could be divided into at least two groups: an alcohol and amine type, and a phenol type.