Renate Klöcking, Carola Kleiner, Ralf Junek, Roland Schubert, André-Michael Beer, Julian Lukanov, Plamen Sagorchev, Hans-Peter Klöcking, and Jürgen I. Schoenherr
Proceedings of the 14th International Peat Congress
bimodal-effect, blood-coagulation, lps-stimulated-tnf-%ce%b1-release, natural-and-synthetic-humic-substances, spontaneous-contractile-activity-of-smooth-muscles
Theme IV. Chemical, physical and biological characteristics of peat
With the aim of developing humic preparations for medical use we investigated two naturally occurring and three synthetic humic substances (HS) for their effects on inflammation, spontaneous contractile activity of smooth muscles, and the reaction time of blood coagulation. The results indicate that low concentrations (1-10 μg/ml) of HS enhance the spontaneous contractile activity of smooth muscle strips from guinea pigs by stimulating alpha(2)-adrenoceptors and dopamine D2 receptors, intermediate HS concentrations (10-250 μg/ml) reduce the release of tumor necrosis factor alpha (TNF-α), an inflammation biomarker, and high HS concentrations (250-1000 μg/ml) act as anticoagulants. Interestingly, a few humic samples were found to exhibit bimodal dose-response curves the reason of which still needs to be clarified.