Werner-Felmayer G, Prast H, Werner E R, Philippu A, Wachter H
Institut für Medizinische Chemie und Biochemie, Universität Innsbruck, Austria.
FEBS Lett. 1993 May 17;322(3):223-6. doi: 10.1016/0014-5793(93)81574-j.
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.
