Einfluß von Albumin und Substratmenge auf den Testosteronstoffwechsel in der isoliert perfundierten Meerschweinchenleber
Influence of Substrate Ratio and Albumin on Testosterone Metabolism in Isolated Perfusion of Guinea Pig Liver
Isolated guinea-pig-livers were perfused in single passage with large doses of 4–14C-Testo-sterone (7,2 mg; spez. act. 1,1 μc/mg) in Krebs-Ringer-Bicarbonate solution. The following metabolites were isolated from the perfusion medium: 6β -Hydroxytestosterone, 6β-Hydroxy-androstenedione, 7α-Hydroxytestosterone, 7α -Hydroxyandrostenedione, Androst-4-ene-3,17-dione, 5β-Androstane-3α,17β -diol and 5β -Androstane-3α -ol-17-one. These compounds have been characterized by their behaviour on a SE-30 and XE-60 column, as free steroids, steroid-acetates and steroid-trimethylsilylethers.
In other experiments the administration of 2,6 g of albumin to 100 ml perfusion medium produces a 20% rise in the amount of free metabolites of testosterone which could be extracted from the perfusing fluid. There is also a significant increase in production of Androstenedione. Other proteins like Haemacel or γ -Globulin don’t cause any significant change in the metabolism of large doses of testosterone. No 17-Hydroxysteroid-dehydrogenase-activity has been observed in the used albumin.
Liver perfusion studies, using small amounts of testosterone (30 μg) have shown a markedly increase of the production of steroidconjugates. In this fraction Hydroxymetabolites of testosterone and 5β -Androstane- α, 17β -diol could be found.