Studies on neurosteroids XII. Determination of enzymatically formed catechol estrogens and guaiacol estrogens by rat brains using liquid chromatography-mass spectrometry-mass spectrometry.

Enzymic formations of catechol- and guaiacol-estrogens by rat brains have been investigated using classical- and catechol-estrogens as substrates, respectively. The incubation mixtures were pretreated with liquid-liquid and/or solid-phase extraction, and the products were identified by comparison with authentic samples using liquid chromatography-mass spectrometry (-mass spectrometry) [LC-MS (-MS)]. The enzymic activities were also determined by measuring the formed products with LC-MS.