| Abstrakt: |
A method is described for the separation, identification and quantitation of endogenous hydrogenated metabolities of corticosterone in rat liver Corticosterone, 5a- and 5ß-dihydrocorticosterone, 3a,11ß,21-trihydroxy-5a-pregnane-3,20-dione, 3ß,11ß,21-trihydroxy-5a-pregnane-3,20-dione, 3a,11ß,21-trihydroxy-5ß-pregnane-3,20-dione, 3ß,11ß,21-trihydroxy-5a-pregnane-3,20-dione, 5a-pregnane-3a,11ß,20a,21-tetrol, 5a-pregnane-3a,11ß,20ß,21-tetrol and 5a-pregnane-3ß,11ß,20ß,21-tetrol are specifically quantitated in one analysis by mass fragmentography all as their O-methyloxime pertrimethylsilyl derivatives. A pronounced difference in the amounts of these nine metabolites between male and female adult rats was found, while in newborn rats only the two tetrahydro-compounds bearing a 5a-hydrogen were detected in both sexes. On the other hand 3a,11ß,1 5a,21-tetrahydroxy-5a-pregnan-20-one was detected only in the adult female as its second prominent metabolite of corticosterone. Corticosterone metabolites being biochemical markers of the sex-linked differentiation of the hepatocytes, their mass fragmentographic assay is proposed as a tool for the quantitative analysis of this type of gene expression. |
