Publications by authors named "W Stammel"

1. We report for the first time on the production and characterization of antibodies against a naturally occurring tetrahydroisoquinoline, namely salsolidine (6,7-dimethoxy-1-methyl-1,2,3,4-tetrahydroisoquinoline). 2.

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Possible effects of various tetrahydroisoquinolines (TIQs) on rat testicular endocrine function were tested in vitro in order to prove whether these compounds, some of which have been claimed to accumulate in alcoholics, may be mediators of the development of Leydig cell insufficiency, a well-known side-effect of ethanol ingestion. TIQ effects on different levels of regulation of testis function were compared in vitro with estrogen effects, since both classes of compounds have structural similarities. Gonadotropin-stimulated testosterone production by testicular Leydig cells was inhibited by tetrahydropapaveroline and isosalsoline, the IC50 values (30 microM) being comparable to those of estradiol (3 microM), 2-hydroxyestradiol (10 microM), and the phytoestrogens, coumestrol (15 microM) and genistein (7 microM); salsolinol (85 microM) and salsoline (240 microM) were less effective, and salsolidine was ineffective.

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The catecholamine metabolites 4-hydroxy-3-methoxy- and 3-hydroxy-4-methoxymandelic acid can be completely separated by reversed-phase high performance liquid chromatography with chemically bonded octadecylsilane as stationary phase and a citrate/ammonium phosphate buffer (pH 4.5) containing 8% methanol as mobile phase. The two isomers can be electrochemically detected and produce different hydrodynamic voltammograms.

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