模拟CO_2气腹对小鼠胃癌腹腔巨噬细胞功能的影响

Effects of Simulative CO2 Pneumoperitoneum on Peritoneal Macrophages Function in Rats with Gastric Cancer

目的探讨模拟不同压力CO2气腹环境下小鼠胃癌腹腔巨噬细胞功能变化以及对胃癌腹腔种植转移的影响。方法建立小鼠前胃癌615小鼠原位种植模型,将其随机分为5组,每组30只:单纯麻醉组、开腹组以及2、4和6 mm Hg(1 mm Hg=0.133 kPa)CO2气腹组。术后每组各取6只小鼠收集培养腹膜巨噬细胞,培养12、24、48和72 h,检测巨噬细胞吞噬功能及NO和TNF-α水平。其余小鼠术后2周时观察小鼠前胃癌细胞腹腔种植转移率及种植结节的总重量。结果各组小鼠术后均无死亡,无腹水产生,各组小鼠平均体重的差异无统计学意义(P>0.05)。在培养12 h时,开腹组小鼠术后腹腔巨噬细胞吞噬中性红值、NO和TNF-α水平均明显高于其他4组(P<0.05),而单纯麻醉组小鼠又明显高于2、4和6 mm Hg CO2气腹组(P<0.05);2 mm Hg CO2气腹组明显高于4和6 mm Hg CO2气腹组(P<0.05),而4 mm Hg和6 mm Hg CO2气腹组间比较差异无统计学意义(P>0.05)。在培养24 h时,6 mm Hg CO2气腹组小鼠术后腹腔巨噬细胞吞噬中性红值、NO和TNF-α水平均明显低于其他4组(P<0.05),其他4组间比较差异无统计学意义(P>0.05)。在培养48 h和72 h时,各组小鼠术后腹腔巨噬细胞吞噬中性红值、NO和TNF-α水平比较差异均无统计学意义(P>0.05)。单纯麻醉组、开腹组以及2、4和6 mm Hg CO2气腹组小鼠前胃癌腹腔种植转移率为分别为100%(24/24)、50.0%(10/20)、47.8%(11/23)、45.5%(10/22)和75.0%(15/20),组间比较6 mm Hg CO2气腹组明显低于单纯麻醉组(P<0.05)而高于其他3组(P<0.05),其他3组间两两比较差异均无统计学意义(P>0.05)。单纯麻醉组、开腹组以及2、4和6 mm Hg CO2气腹组小鼠前胃癌腹腔种植结节重量分别为(1.24±0.48)g、(1.02±0.38)g(、0.96±0.33)g、(0.93±0.45)g和(1.18±0.37)g,各组间比较差异均无统计学意义(P>0.05)。结论高压力(6 mm Hg)CO2气腹可较长时间抑制胃癌小鼠腹腔巨噬细胞的吞噬与分泌功能,促进胃癌的腹腔种植转移。

Objective To investigate the changes of peritoneal macrophages function of mice with gastric cancer in the CO2 pneumoperitoneum environment,as well as its effect on the peritoneal metastasis of gastric cancer.Methods An orthotopic implantation model of mouse forestomach cancer was established using the 615 mouse.The mice bearing tumors were randomly divided into five groups（n=30）： anesthesia alone,laparotomy,and 2,4,and 6 mm Hg CO2 insufflation groups.Peritoneal macrophages were collected from six mice in each group and cultured.The macrophage phagocytic function on neutral red and the levels of NO and TNF-α produced by macrophages were measured after 12,24,48,and 72 h of culture.The remaining mice were observed after two weeks for the rate of peritoneal metastasis of forestomach cancer cells and the total weight of implanted nodules.Results No death and ascites were found and the difference of weight body was not significant in all mice（P0.05）.The uptake of neutral red by peritoneal macrophages and the levels of NO and TNF-α secreted by peritoneal macrophages in the laparotomy group after 12 h of culture were all significantly higher than those in other four groups（P0.05）.The corresponding values in the 2,4,and 6 mm Hg CO2 insufflation groups after 12 h were all significantly lower than those in the anesthesia alone group（P0.05）.Among three insufflation groups,the corresponding values in the 2 mm Hg after 12 h were significantly higher than those in the 4 and 6 mm Hg CO2 insufflation group,though the difference in the two latter was not significant（P0.05）.The uptake of neutral red by peritoneal macrophages and the levels of NO and TNF-α secreted by peritoneal macrophages in the 6 mm Hg CO2 insufflation group after 24 h of culture were all significantly lower than those in other four groups（P0.05）,while the difference in the four groups was not significant（P0.05）.The uptake of neutral red by peritoneal macrophages and the levels of NO and TNF-α secreted by peritoneal macrophages after 48 h and 72 h were not significantly different in the five groups（P0.05）.The rate of peritoneal metastasis of mice was significantly lower in the 6 mm Hg insufflation CO2 group（75.0%,15/20） than that in the anesthesia alone group（100%,24/24）,P0.05,but higher than other three groups（P0.05）,which was not different in 2 mm Hg（47.8%,11/23）,4 mm Hg insufflation group（45.45%,10/22） and laparotomy group（50.0%,10/20）,P0.05.The total weight of implanted nodules of mouse forestomach cancer was（1.24±0.48） g,（1.02±0.38） g,（0.96±0.33） g,（0.93±0.45） g,and（1.18±0.37） g in the anesthesia alone group,the laparotomy group,and 2,4,and 6 mm Hg CO2 insufflation group,and the difference was not significant（P0.05）.Conclusion High pressure（6 mm Hg） CO2 pneumoperitoneum can constantly inhibit the phagocytosis and cytokine secretion functions of peritoneal macrophages in gastric cancer-bearing mice and promote peritoneal implantation of gastric cancer.