Brudel M, Kertscher U, Berger H, Mehlis B
Institute of Molecular Pharmacology, Berlin, Germany.
J Chromatogr A. 1994 Feb 11;661(1-2):55-60. doi: 10.1016/0021-9673(94)85177-8.
Gonadotropin-releasing hormone (GnRH) derivatives are used in cancer therapy, but relatively little is known about their metabolic fate in the organism. This paper describes the application of high-performance liquid chromatography combined with electrospray mass spectrometry to identify the degradation products resulting from the incubation of two GnRH analogues, D-Phe6-GnRH and DSer(OtBu)6-desGly10-GnRH-ethylamide (buserelin) with rat kidney membranes. Reversed-phase columns were applied with gradient elution using a flow-rate of ca. 2 microliters/min to the mass spectrometer. Post- and precolumn stream splitting were employed to adjust the flow-rates for columns of 2 and 0.32 mm I.D. The pattern of peptide degradation products obtained with this method indicates that a defined proteolytic membrane enzyme system is responsible for these catabolic processes.
