Immunological activation and enhancement of betaA4 amyloid protein synthesis after injury into the rat brain

The effect of T3 (triiodothyronine) on the induction of tubulin in hypothyroid developing rat brain has been examined using organ cultures of brains from late fetal, neonatal and postnatalrats. The neonatal brain displayed maximum sensitivity to T3. Hypothyroidism resulted in a 26% decline in the level of tubulin in the neonatal brain as opposed to a 5–15% decline in the fetal or postnatal brain. Exposure of the hypothyroi d neonatal brain to T3 for 2 h in culture led to a 61% rise in the level of tubulin in contrast to a 41% increase seen in the case of normal brain. Total protein synthesis was not significantly affected. The preferential decline of tubulin in the neonatal hypothyroid brain, its enhanced sensitivity to T3 compared to normal brain, and the coincidence of the period of sensitivity to that of brain maturation indicate that the regulation of the level of tubulin by T3 in the developing brain is a natural ontogenic phenomenon.

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Protein synthesis in rat brain during sleep

Neuropharmacology ◽

10.1016/0028-3908(81)90177-5 ◽

1981 ◽

Vol 20 (5) ◽

pp. 457-460 ◽

Cited By ~ 30

Author(s):

C. Shapiro ◽

P. Girdwood

Keyword(s):

Protein Synthesis ◽

Rat Brain

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Quantitative Measurements of Regional Glucose Utilization and Rate of Valine Incorporation into Proteins by Double-Tracer Autoradiography in the Rat Brain Tumor Model

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1989.12 ◽

1989 ◽

Vol 9 (1) ◽

pp. 87-95 ◽

Cited By ~ 22

Author(s):

Michihiro Kirikae ◽

Mirko Diksic ◽

Y. Lucas Yamamoto

Keyword(s):

Protein Synthesis ◽

Brain Tumor ◽

Rat Brain ◽

Brain Tissue ◽

Glucose Utilization ◽

Tumor Model ◽

Normal Brain ◽

Normal Brain Tissue ◽

Rat Brain Tumor ◽

Brain Tumor Model

We examined the rate of glucose utilization and the rate of valine incorporation into proteins using 2-[18F]fluoro-2-deoxyglucose and L-[1-14C]-valine in a rat brain tumor model by quantitative double-tracer autoradiography. We found that in the implanted tumor the rate of valine incorporation into proteins was about 22 times and the rate of glucose utilization was about 1.5 times that in the contralateral cortex. (In the ipsilateral cortex, the tumor had a profound effect on glucose utilization but no effect on the rate of valine incorporation into proteins.) Our findings suggest that it is more useful to measure protein synthesis than glucose utilization to assess the effectiveness of antitumor agents and their toxicity to normal brain tissue. We compared two methods to estimate the rate of valine incorporation: “kinetic” (quantitation done using an operational equation and the average brain rate coefficients) and “washed slices” (unbound labeled valine removed by washing brain slices in 10% thrichloroacetic acid). The results were the same using either method. It would seem that the kinetic method can thus be used for quantitative measurement of protein synthesis in brain tumors and normal brain tissue using [11C]-valine with positron emission tomography.

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