Effect of vaporized perfluorocarbon inspiration on cell apoptosis of intestine mucosa: experiment with pigs with acute lung injury

Abstract

To investigate the effect of vaporized perfluorocarbon (PFC) inspiration on cell apoptosis of intestine mucosa. 18 piglets are randomly assigned to 3 groups, VMV group (n=8), undergoing intra-bronchial infusion of dioctyl sodium sulfosuccinate so as to cause acute lung injury (ALI), then routine mechanical ventilation (MV) for 8 h during which vaporized PFC inspiration was given for 2 h, and then killed to have the small intestine taken out, CMV group (n=8), undergoing routine MV for 8 h after the establishment of ALI model as MV control group, and sham operation group (n=2), undergoing only laparotomy to take out the small intestine. Apoptosis index of intestine mucosa was examined by TUNEL. Immunohistochemistry was used to detect the protein expression of BAX and bcl-2. RT-PCR was used to detect the mRNA expression of BAX and bcl-2. The apoptotic cells were mainly distributed in the intestinal villi of the VMV and CMV groups, and only a few apoptotic cells could be seen in the sham operation group. The apoptosis rate of the VMV group was (22.9+/-2.3)%, significantly lower than that of the CMV group [(70.6+/-3.4)%, P<0.05]. The protein expression of BAX of the VMV group was significantly lower than that of the CMV group (P<0.05), and the protein expressing of bcl-2 of the VMV group was significantly higher than that of the CMV group (P<0.05). The mRNA expression of BAX of the VMV group was 7.10+/-0.32, significantly lower than that of the CMV group (9.29+/-1.06, P<0.05), and the MRNA expression of bcl-2 of the VMV group was 10.29+/-2.51, significantly higher than that of the CMV group (5.18+/-1.08, P<0.05). The mRNA expression and protein expression of BAX and bcl-2 were all at very low levels in the sham operating group. PFC vaporized inspiration may reduce mucosa apoptosis of small intestine, with the possible mechanism of inhibiting the expression of the BAX gene and raising the expression of the bcl-2 gene.