Detection of endogenous salsolinol in neonatal rat tissue by a radioenzymatic--thin-layer chromatographic assay

A sensitive radioenzymaticc--thin-layer chromatographic assay for the quantitative analysis of the tetrahydroisoquinoline alkaloid, salsolinol, in plasma and neonatal rat tissue is described. The assay involves the enzymatic O-methylation of salsolinol by catechol-O-methyltransferase in presence of [3H]S-adenosylmethionine, and subsequent separation by thin-layer chromatography of the resultant [3H]O-methyl-salsolinol from the O-methylated derivatives of dopamine, epinephrine and norepinephrine. The method allows the detection of as little as 100 pg salsolinol per g tissue, and the accurate quantitation of as little as 100 pg/ml plasma and 500 pg/g tissue. This assay permitted the detection of trace amounts of endogenous salsolinol in neonatal rat tissue (less than 500 pg/g tissue).