Z Zakładu Biologii Medycznej Instytut Medycyny Wsi im. W. Chodźki w Lublinie
MONZ 2009;15(4):566–575
W artykule przedstawiono mechanizm działania szlaku kynureninowego, jak i rolę jaką odgrywa on w organizmie w procesach fizjologicznych i patologii. Omówiono także właściwości i funkcje jednego z głównych metabolitów tego szlaku, kwasu kynureninowego.

Kynurenic pathway is the main non-protein route of the conversion of tryptophan. For many years, an interest in this pathway was limited to the synthesis of the nicotinic acid, which is a substrate for the basic enzymatic reaction cofactor – NAD. However, indirect metabolites of the kynurenic pathway are also important, which exert an effect on such processesand phenomena as: proliferation of cells, regulation of anti- and pro-oxidants, excytotoxicity, neurodegradation or inflammatory processes. One of the metabolites of the kynurenic pathway is kynurenic acid. This acts as an antagonist towards all types of glutomineralgic receptors, and may also regulate peripheral cellular response by the activation of GPR35 receptors. Its role outside the nervous system remains unclear, despite the fact that its presence was observed in many body fluids. It was also detected in the lumen of the intestine, where intestinal bacterial flora seems to be its main producer. KYNA also occurs in many food products and may be absorbed from the alimentary tract into bloodstream.
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