Science, Vol 219, Issue 4580, 75-77
Copyright © 1983 by American Association for the Advancement of Science
Effects of tyrosine administration on serum biopterin in normal controls and patients with Parkinson's disease
T Yamaguchi,
T Nagatsu,
T Sugimoto,
S Matsuura,
T Kondo,
R Iizuka,
and
H Narabayashi
After administration of tyrosine, total concentration of biopterin, the cofactor for tyrosine hydroxylase, was increased in the striatum, adrenal glands, and serum of rats, and in the serum of humans. Serum biopterin is lower in patients with Parkinson's disease than in normal controls. After oral administration of tyrosine, the increase in serum biopterin concentration was smaller in patients with Parkinson's disease (less than twofold) than in healthy controls (three-to sevenfold). These results suggest that tyrosine may have a regulatory role in biopterin biosynthesis and that patients with Parkinson's disease may have some abnormality in the regulation of biopterin biosynthesis.