Rates of local cerebral protein synthesis in fetal and neonatal
sheep.
Abrams, R. M., D. J. Burchfield, Y. Sun, and C. Beebe Smith.
Department of Obstetrics and Gynecology and Department of
Pediatrics, University of Florida Medical Center, Gainesville,
Florida, U.S.A. and Laboratory of Cerebral Metabolism, National
Institute of Mental Health, U.S. Public Health Service, Department of
Health and Human Services, Bethesda, Maryland, U.S.A.
APStracts 3:0408R, 1996.
During gestation there is likely to be a constantly changing rate of
protein synthesis in brain which may exhibit regional specificity.
With the use of the quantitative autoradiographic L-[1-14C]leucine
method for the determination of local rates of leucine incorporation
into cerebral protein (lCPSleu) we have sought to characterize this
important process. LCPSleu was measured in nine fetal sheep (118-139
days gestation) and five newborn lambs (1-5 days of age). In other
experiments the fraction of leucine in the precursor pool for protein
synthesis in the brain derived from the arterial plasma was
determined to be 0.57 +/- 0.04 (mean +/- SEM) in one fetus and two
lambs. This value was used in the calculation of lCPSleu in 35
regions of the central nervous system, pineal and whole brain.
Regardless of age, lCPSleu was highest in the pineal, brain stem and
hypothalamic nuclei and lowest in white matter. In sensorimotor
cortex, corona radiata, pyramidal tracts and whole brain, lCPSleu was
positively correlated with prenatal age (P 0.05). These increases in
lCPSleu probably reflect myelination in the cerebrum which is known
to occur in the latter part of gestation.
Received 9 July 1996; accepted in final form 30 October 1996.
APS Manuscript Number R389-6.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996