Ghosh R K, Medda A K
Endokrinologie. 1982 Jul;79(3):355-61.
Effects of three consecutive days injections of thyroxine (T4) of different doses (1, 2 and 4 micrograms/g of body weight) on different parts of the brain of Singi fish were studied. T4 enhanced the cranio-somatic index and the weight of different substructures of brain, viz., cerebrum, cerebellum midbrain and medulla oblongata, of Singi fish at 25 degrees C. Compared to the control, the protein content of cerebrum increased with all doses of T4 (1, 2 and 4 micrograms/g) and the RNA content of this region increased only with higher doses (2 and 4 micrograms/g). Cerebellum appeared to be relatively less responsive than cerebrum; T4 at the dose of 4 micrograms/g was only effective in increasing the protein content of the cerebellum, although the RNA content of this region was enhanced with both 2 and 4 micrograms of T4 per g. In midbrain and medulla oblongata, the protein content was elevated only with higher doses (2 and 4 micrograms/g) and RNA content was enhanced with all doses of T4 used. T4 injections did not cause any alteration of the DNA content of cerebrum and cerebellum, but in midbrain this cellular constituent increased in amount with all doses of T4 and in medulla oblongata it was increased with the dose of 2 or 4 micrograms of T4 per g body weight.
研究了连续三天注射不同剂量（1、2和4微克/克体重）甲状腺素（T4）对单须鱼大脑不同部位的影响。在25摄氏度时，T4提高了单须鱼的颅体指数和大脑不同亚结构（即大脑、小脑、中脑和延髓）的重量。与对照组相比，所有剂量的T4（1、2和4微克/克）均使大脑的蛋白质含量增加，且仅较高剂量（2和4微克/克）使该区域的RNA含量增加。小脑似乎比大脑的反应相对较小；4微克/克剂量的T4仅能有效增加小脑的蛋白质含量，尽管每克2和4微克的T4均能提高该区域的RNA含量。在中脑和延髓中，仅较高剂量（2和4微克/克）能提高蛋白质含量，且所有使用剂量的T4均能提高RNA含量。注射T4并未引起大脑和小脑DNA含量的任何改变，但在中脑中，所有剂量的T4均使该细胞成分的量增加，在延髓中，每克体重2或4微克的T4剂量使其增加。
