摘要
大鼠硒耗竭6周后,其肝、肾、全血、褐脂肪、垂体等组织的谷胱甘肽过氧化物酶(GPX)及5′-脱碘酶活性极显著大幅度下降,而肝肾谷胱甘肽硫转移酶(GST)活性升高了。各组织 GPX及 GST 酶活性不受冷应激的影响;急促冷应激导致大鼠血浆中四碘甲腺原氨酸(T_4)、三碘甲腺原氨酸(T_3)和促甲状腺激素(TSH)的水平升高。大鼠在硒缺乏状态下,其 T_4,TSH 的上升幅度更大,而 T_3的上升幅度略小。冷应激不影响肝、肾及垂体等组织的5′-脱碘酶活性,只是脑组织的5′-脱碘酶活性略有下降,肩胛间褐脂肪组织重量和5′-脱碘活性分别显著大幅度下降和升高,硒营养缺乏明显减小其变化的幅度,说明硒缺乏会破坏大鼠的非寒颤性产热功能。
After six weeks of selenium depletion,the glutathione peroxidase(GPX)and 5'-deiodinase activities of rat liver,kidney,blood,brown adipose tissue(BAT)and pituitary were much lowered significantly;but the liver and kidney glutathione S-transferase activities were elevated.The activities of GPX and GST were not influened by cold stress.Rats' plasma thyroxine and Thyrotropin level were significantly much elevated after acute cold exposure. and the magnitude of elevation of thyroxine and thyrotropin was greater in selenium-deficient rats.but that of thyronine was slightly smaller;the activities of 5'-deiodinase in liver and kidney did not change at all except that in brain decreased and that in BAT increased;the weight of interscapular BAT also decreased significantly.The magnitude of change was de- creased under the selenium-deficient status.The results suggest that selenium deficiency may impair the non-thievering thermogenic function of BAT.
关键词
硒
冷应激
甲状腺激素
selenium
cold stress
thyroid hormones
thyrotropin
5'-deiodinase
brown adipose tissue
