促甲状腺激素对甲状腺细胞胞内游离钙和钙调蛋白的影响

本文研究TSH和forskolin对原代培养的猪甲状腺细胞Ca~(2+)]_i和钙调蛋白的影响。结果表明,TSH可引起甲状腺细胞Ca~(2+)]_1急性升高。此反应是剂量依赖关系,而与细胞外钙的存在与否无关。其反应性在细胞单层高于细胞是液,近汇合细胞单层高于汇合细胞单层。TSH作用3天,可使甲状腺细胞的钙调蛋白含量增高,此作用与TSH对甲状腺细胞数的影响无关。Forskolin对甲状腺细胞的Ca~(2+)]_i和钙调蛋白均无明显的影响。

Effects of Thyrotrophin on Intracellular Free Calcium and Calmodulin in Thyroid Cells

The effects of thyrotrophin (TSH)and forskolin were examined on intrace-llular free calcium (Ca2+]l)and calmodulin in normal pig thyroid cells in primary culture.TSH was found to produce acute increases inCa2+]l in pig cells.Responses were seen at concentrations of TSH between 0.01 and 10mU/mL.Sensitivity to TSH was greater in adherent monolayers of cells rather than cell suspensions and was also greater in subconfluent rather than confluent monolayers of cells.The increase in Ca2+], in response to TSH represented just over a doubling in Ca2+]l whether examined at 22C or 37C.Forskolin falied to affect Ca2+]l TSH increased Ca2+]l in the absence of extracellular calcium.TSH, but not forskolin, produced a significant increase in intracellular calmodulin after 3 days of culture of cells with TSH.The increase in calmodulin was of the order of 60% and did not relate to any effect of TSH on thyroid cell number.