Premium
TRYPTOPHAN 5‐HYDROXYLASE: APPROXIMATION OF HALF‐LIFE AND RATE OF AXONAL TRANSPORT
Author(s) -
Meek J. L.,
Neff N. H.
Publication year - 1972
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1972.tb05096.x
Subject(s) - tryptophan hydroxylase , colchicine , tryptophan , endocrinology , medicine , spinal cord , serotonin , axoplasmic transport , enzyme , enzyme assay , chemistry , biology , biochemistry , anatomy , serotonergic , neuroscience , amino acid , receptor
—The half‐life of tryptophan 5‐hydroxylase (EC 1.14.3) in rats was estimated from the return of enzyme activity after administration of p ‐chlorophenylalanine and from the decline of enzyme activity in spinal cord after transection or an intraspinal injection of colchicine. The half‐life was 2–3 days. Axonal transport of enzyme, estimated from the reappearance of activity in consecutive portions of spinal cord after treatment with p‐chlorophenylalanine, was of the order of 5–7 mm/day. This rate is characteristic of 'slow’axonal flow. Our results suggest that changes in the synthesis of new enzyme are probably not responsible for acute changes in the turnover of serotonin.