Effects Of Glutamine On Proliferation And HSP70Expression Of Mammary Epithelial Cells In Dairy Cows

The mammary epithelial cells of dairy cow cultured with different dose of Gln were treated with37℃and higher temperature. Cell activity, proliferation and the expression of HSP70were determined by MTT, lactate dehydrogenase (LDH) kit, gel electrophopresis and reverse transcription-Polymerase Chain Reaction (RT-PCR), respectively. The aim of this paper was to reveal the influence of different Gln doses on cells activity, proliferation, the effect on the cell hurt cause by teat stress and induced effect on the expression of HSP70mRNA. This thesis includes two sections.1. Effect of the different dose of Gln on cells activity, proliferation and HSP70mRNA expression of dairy cow mammary epithelial cellsBovine mammary epithelial cells were cultured in DMEM+10%CS medium with different Gln from0～8mmol/L at37℃then cells and supernatant were collected. The cell growth and proliferation, activity of LDH, and expression of Bcl-2/Bax as well as heat shock protein70(HSP70) were detected with MTT, lactate dehydrogenase (LDH) kit and reverse transcription-Polymerase Chain Reaction (RT-PCR) respectively. Therefore to investigate the effect of the Gln on activity, proliferation and relation to the HSP70expression in vitro cultured mammary epithelial cells. The result showed that the cells activity depended on the dose of Gln. The treat group with2mmol/L Gln showed the hightest level of cell activity and expressions of Bcl-2/Bax mRNA. The expression of HSP70mRNA could be induced by Gln and increased as the increased dose of Gln.2. Effect of heat stress on activity, proliferation and HSP70mRNA expression of mammary epithelial cells cultured with different doses of GlnBovine mammary epithelial cells were treated with37℃、39℃、41℃、43℃and the optimum temperature for heat stress groups was determined. Cells were cultured with different Gln doses from0～8mmol/L at41℃then were collected together with supernatant. The purpose was to reveal the hurt on the cells with different temperature treatments, and the extent of hurt effect of different Gln doses on the cells activity, proliferation and induced expression of HSP70mRNA in heat condition. The result implied that the apoptosis rate of cells increase with set up of temperature. The group at43℃showed the higher rate than the one at41℃, the treatment with39℃endured the lowest cell apoptosis rate.In high temperature condition significant inhibited effect was found in the experimental groups (0～0.5mmol/L). Cells activity was enhanced in the groups of4and8mmol/L. The expression of HSP70mRNA depended the dose of Gln. Compared to the control one, the expressions of HSP70in treat groups (0～0.5mmol/L) were lower, while the groups of4and8mmol/L increased by50.62%、91.56%respectively, which showed a significant effect. The activity of cells under heat stress could be enhanced with hight expression of HSP70mRNA, which induced by high dose of Gln.