Research on immunoenhancing effect of hypertonic saline resuscitation of hemorrhagic shock model in mice

我们研究了高渗盐水复苏对小鼠失血性休克复苏后CD4^+CD25^+调节性T细胞和γδT细胞凋亡的影响。方法：选用8 ~ 12周龄雄性C57BL/6J小鼠。小鼠麻醉并抽血，直至平均动脉压达到40±5mmHg，并维持60分钟。复苏方法：HS+SB；高渗生理盐水（4ml/Kg, 7.5% NaC1:HS）和出血（SB）， 2LR+SB；分别于复苏后2、6、24、48h采集胸腺和脾脏标本。流式细胞术检测CD4^+CD25^+调节性T细胞和γδT细胞。AnnexinV检测细胞凋亡。结果：1)高渗盐水复苏对CD4^+CD25^+调节性T细胞和γ8T细胞无明显影响。2) 6h、24h、48h脾脏调节性T细胞较对照组增加。(P < 0.05)。3)脾脏和胸腺的γδT细胞和γδT细胞凋亡均未增加。讨论：高渗盐水复苏的免疫增强作用与CD4^+CD25^+调节性T细胞和γδT细胞无关。失血性休克复苏后的免疫抑制状况可能与CD4^+CD25^+调节性T细胞有关。

We examined effects of hypertonic saline resuscitation on CD4^+CD25^+ regulatory T cells and γδT cells after hemorrhagic shock and resuscitation in relation to apoptosis in mice. Methods: Male C57BL/6J mice 8 to 12 weeks old were used. Mice were anesthetized and blood was withdrawn until a mean arterial pressure of40±5mmHg was reached, and maintained for 60 min. Resuscitation was performed as follows: HS+SB; with hypertonic saline (4ml/Kg of 7.5% NaC1:HS) and shed blood (SB), 2LR+SB; with lactated Ringer' s solution (2 times the volume of the shed blood) and SB. Samples of thymus and spleen were harvested at 2,6,24 and 48h after resuscitation. CD4^+CD25^+ regulatory T cells and γδT cells were estimated using flow cytometry. Apoptosis was assessed with AnnexinV. Results: 1) Hypertonic saline resuscitation did not affect on CD4^+CD25^+ regulatory T cells and γ8T cells. 2) Regulatory T cells at 6h,24h and48h in spleen increased compared with controls. (P<0.05). 3) Apoptotic γδT cells and γδT cells both in spleen and thymus was not increased compared with controls. Discussion: Immunoenhancing effect of hypertonic saline resuscitation did not correlated with CD4^+CD25^+ regulatory T cells and γδT cells. Immunosuppressive condition after hemorrhagic shock and resuscitation may be related with CD4^+CD25^+ regulatory T cells.