Related Experiment Videos
Induction of GTP cyclohydrolase I by bacterial lipopolysaccharide in the rat
G Werner-Felmayer1, H Prast, E R Werner
1Institut für Medizinische Chemie und Biochemie, Universität Innsbruck, Austria.
Abstract:
A 2- to 3-fold increase of GTP cyclohydrolase I (E.C. 3.5.4.16), the key enzyme of tetrahydrobiopterin biosynthesis from GTP, was observed in cerebellum, remaining brain, liver, spleen, and adrenal gland of rats treated with a single dose of lipopolysaccharide (LPS). This led to increased biopterin levels in tissues but not in plasma. Parallel induction of nitric oxide (NO) synthase was indicated by a 10- to 100-fold increase of plasma nitrate levels 6 and 12 hours after injection of LPS. Furthermore, systolic blood pressure was reduced significantly by 23%. Our results demonstrate induction of tetrahydrobiopterin biosynthesis after LPS treatment in vivo.