ABSTRACT
To further studies of the metabolism of 26-hydroxycholesterol in fetal and neonatal life, a deuterated compound was prepared from kryptogenin by Clemmensen reduction. The spectra of the deuterated 26-hydroxycholesterol showed that five to nine deuterium atoms were incorporated per 26-hydroxycholesterol molecule, with the maximum incorporation of eight deuterium atoms. The deuterated compound was recovered unchanged from the feces of a child following oral administration. Comparison of the ratio of deuterated to protium compound indicated the presence of an endogenous pool of 26-hydroxycholesterol. Parenteral administration of the compound to a hamster indicated metabolism to deuterated chenodeoxycholic acid. The compound is useful as an isotope tracer for studies of the endogenous metabolism of 26-hydroxycholesterol.