Smith R M, Patel A J, Kingsbury A E, Hunt A, Balázs R
Brain Res. 1980 Oct 6;198(2):375-87. doi: 10.1016/0006-8993(80)90751-9.
The effect of thyroid status on beta-adrenergic receptor binding and 5'-nucleotidase activity was studied in the forebrain and the cerebellum of the rat during the first 5 postnatal weeks. The developmental increase in beta-adrenergic receptor binding was significantly depressed in thyroid deficiency in both the forebrain and the cerebellum. The effect was more pronounced in the cerebellum, where at day 35 the concentration and the total number of beta-adrenergic receptor sites were reduced by 35% and 50% respectively. In contrast, hyperthyroidism had no significant effect on the development of beta-adrenergic receptors in the brain. On the other hand, hyperthyroidism led to a sustained increase in the forebrain in the activity of 5'-nucleotidase, an enzyme which is also associated with plasma membranes and has been proposed to play some role in neurotransmission. In thyroid deficiency the enzyme activity was markedly depressed. The effect was significant from day 12 in the cerebellum and from day 21 in the forebrain, the maximal depression, at day 21, being 55% and 45% respectively. In comparison with these plasma membrane markers, the accretion of membranous proteins was less affected: although this was retarded in hypothyroidism and advanced in hyperthyroidism there was no residual effect at 35 days except those attributable to changes in organ size. The results indicated, therefore, that the biochemical specialization of cells, as reflected in certain plasma membrane constituents, are chatacteristically influenced in the developing brain by thyroid disorders.
研究了出生后前5周内甲状腺状态对大鼠前脑和小脑中β-肾上腺素能受体结合及5'-核苷酸酶活性的影响。甲状腺功能减退时，前脑和小脑中β-肾上腺素能受体结合的发育性增加均显著受到抑制。这种影响在小脑中更为明显，在出生后第35天，小脑β-肾上腺素能受体位点的浓度和总数分别降低了35%和50%。相反，甲状腺功能亢进对脑中β-肾上腺素能受体的发育没有显著影响。另一方面，甲状腺功能亢进导致前脑中5'-核苷酸酶的活性持续增加，5'-核苷酸酶是一种也与质膜相关的酶，有人提出它在神经传递中起一定作用。甲状腺功能减退时，该酶活性明显降低。在小脑，从出生后第12天开始有显著影响，在前脑从出生后第21天开始有显著影响，在出生后第21天最大抑制率分别为55%和45%。与这些质膜标记物相比，膜蛋白的增加受影响较小：虽然在甲状腺功能减退时膜蛋白增加受阻，在甲状腺功能亢进时膜蛋白增加提前，但在出生后第35天除了因器官大小变化引起的影响外没有残留影响。因此，结果表明，某些质膜成分所反映的细胞生化特化在发育中的大脑中受到甲状腺疾病的特征性影响。
