title: Investigations on myelination in vitro. Regulation by thyroid hormone in cultures of dissociated brain cells from embryonic mice.
abstract: Cultures of dissociated brain cells from embryonic mice were used to study the influence of thyroid hormone on myelination in vitro. Synthesis of myelin-associated lipids such as cerebrosides and sulfatides was used as an index for myelination. An experimental design, in which the cells were grown on medium containing serum from a thyroidectomized calf, was employed to demonstrate the direct effect of L-3,5,3'-triiodothyronine (T3Y on the biosynthesis of myelin lipids. The cells grown in the presence of hypothyroid calf serum which contained very low levels of thyroid hormones (T4 (thyroxine), 1.2 microgram/ml; T3, less than 25 ng/100 ml) compared to normal serum (T4, 5.8 microgram/ml; T3, 110 ng/100 ml) showed a diminished synthesis of myelin-associated glycolipids. This reduced activity could be restored to normal by including T3 (13 ng/ml) in the medium.
mesh_terms: D000818:Animals; D001769:Blood; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D003470:Culture Media; D004622:Embryo, Mammalian; D005260:Female; D005690:Galactose / Q000378:metabolism; D006017:Glycolipids / Q000096:biosynthesis*; D051379:Mice; D009186:Myelin Sheath / Q000378:metabolism*; D011247:Pregnancy; D013431:Sulfates / Q000378:metabolism; D013965:Thyroidectomy; D013974:Thyroxine / Q000494:pharmacology; D014284:Triiodothyronine / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D006017:Glycolipids; D013431:Sulfates; D014284:Triiodothyronine; D013974:Thyroxine; D005690:Galactose