Triiodothyronine does not affect the average incorporation of L-[35S]methionine in rat brain structures.
The autoradiographic method with L-[35S]methionine was used to examine the effect of acute administration of L-triiodothyronine on local rates of brain protein synthesis in free-moving adult rats. Triiodothyronine was given intraperitoneally at doses of 12.5 or 25 micrograms kg-1. It did not modify the rate of plasma methionine incorporation in the 40 brain regions examined, despite a 4- to 8-fold increase of plasma free triiodothyronine levels. Biochemical analysis confirmed that triiodothyronine (25 micrograms kg-1) had no apparent effect on the overall rate of protein synthesis in the brain as a whole. These results suggest that changes in the circulating levels of thyroid hormones do not exert a general and direct metabolic effect in brain of intact adult rats.
Sermet
E
E
Laboratoire d'anatomie pathologique, UFR A. Carrel, Lyon, France.
Gay
N
N
Baubet
V
V
Giaume
M
M
Dalery
J
J
Bobillier
P
P
D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000502:physiology; D002540:Cerebral Cortex / Q000378:metabolism; D004027:Diencephalon / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D008715:Methionine / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013963:Thyroid Hormones / Q000097:blood / Q000502:physiology; D014284:Triiodothyronine / Q000097:blood* / Q000502:physiology
D011506:Proteins; D013963:Thyroid Hormones; D014284:Triiodothyronine; D008715:Methionine