Disturbances of Myelination in Neonatally Thyroidectomized Rat Brains
It is well known that thyroid deficiency in the neonatal period results in impaired development of the central nervous system. The effects’ in the rats of neonatal hypothyroidism have been the subject of extensive histological (Hamburgh 1969), behavioural (Eayrs and Levine 1963), electroencephalographic (Hatotani and Timiras 1967) and biochemical (Gell et al. 1967, Gómez and Ramirez de Guglielmone 1967, Balázs et al. 1968) studies. To date, however, little attention has been focussed on the cerebral lipids in the states of thyroid dysfunction. The recent works suggested that the lipid content and its fatty acid patterns in the myelin sheath were different from those in the whole brain, the gray matter and the white matter (O’Brien and Sampson 1965a, b). Despite a few studies (Cuarón et al. 1963, Walravens and Chase 1969), the data on the lipid analyses of isolated brain myelin from the hypothyroid animals are completely lacking. The present work was designed to examine in the rats the influences of neonatally induced hypothyroidism on the myelination in terms of changes in myelin lipid content and in normal fatty acid composition of the individual sphingolipid.
KeywordsMyelin Sheath Fatty Acid Pattern Myelin Lipid Nervonic Acid Hypothyroid Animal
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