甲状腺素T4对体外高温培养奶牛乳腺上皮细胞生长和凋亡的影响

以体外培养的奶牛乳腺上皮细胞为模型,采用台盼蓝染色绘制生长曲线,细胞流式检测细胞凋亡,以正常培养温度(38℃)为对照,研究体外高温培养条件下(42℃),添加不同浓度(0.01、01和1mol/L)甲状腺素(thyroxine,T4)对细胞生长和凋亡的影响.结果表明,不同浓度的T4在38℃有促进奶牛乳腺上皮细胞生长的趋势,但是变化不显著(P>0.05),而T4对缓解高温所造成的乳腺上皮细胞的生长抑制作用也不显著(P>0.05);不同的T4都能够极显著缓解42℃培养1 h和3 h的奶牛乳腺上皮细胞的凋亡(P<0.01),并且对缓解42℃培养3 h的细胞凋亡效果更加明显,但是对42℃培养5 h和8 h的细胞,仅1 μmol/L的T4能够极显著缓解其凋亡(P<0.01).结果提示,T4对高温造成的奶牛乳腺上皮细胞的生长抑制没有明显的缓解作用,但能缓解高温诱导的奶牛乳腺上皮细胞凋亡.

The Effects of Thyroxine on Cell Growth and Apoptosis of Bovine Mammary Epithelial Cells Under Heat Circumstance in vitro

The experiment was conducted to study the effects of thyroxine(T4)on cell growth and apoptosis of bovine mammary epithelial cells cultured under heat circumstance in vitro.Bovine mammary epithelial cells were cultured with T4 of different concentration(0,0.01,01and 1 μmol/L),which were exposed at 42℃ as heat treatment model and 38℃ as control.Cell growth and cell apoptosis were detected by trypan blue dying and flow cytometry FCM,respectivelyThe results showed as follows:(1)Cell growth stagnated at 42 ℃,and the cell number decreased extremely markedly(P<0.01)than control 38℃,but T4 had no significant effect on alleviating the growth inhibition caused by high temperature(P>0.05).(2)Every experimental concentration of T4 can significantly alleviate the apoptosis of mammary epithelial cells cultured 42℃ 1 and 3 h(P<0.01),and there was obvious effect on cells cultured at 42℃ 3 h.However,only 1 μmol/L T4 can significantly alleviate the apoptosis of cells cultured 42℃ 5 h and 8 h(P<0.01).In conclusion,T4 has no significant effect on alleviating the growth inhibition caused by high temperature,but at the same time T4 plays a role on alleviating cell apoptosis induced by high temperature.