Carbon dioxide pneumoperitoneum reduces levels of TNF-a mRNA in the brain, liver, and peritoneum in mice

Abstract

Background: Cytokines are important regulators of the biological response to surgical stress. The aim of this study was to determine whether the CO2 pneumoperitoneum would change the expression of TNF-a mRNA in the visceral organs, including the brain, in mice. Methods: Mice were randomly assigned to one of six groups: control, anesthesia alone, insufflation with carbon dioxide, insufflation with air, laparotomy by short incision, or laparotomy by long incision. The brain, liver, jejunum, and peritoneum were harvested either 3 or 24 h after surgery. Levels of TNF-a mRNA in each tissue was measured by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Results: The air insufflation group showed higher TNF-a mRNA levels in the brain and liver than the short-incision group. Levels of TNF-a mRNA in the brain, liver, and peritoneum were lower in the CO2 pneumoperitoneum group than in the air insufflation group. Plasma IL-6 and catecholamine in the urine were lower in the CO2 pneumoperitoneum group than the air insufflation group. Conclusion: Reduced synthesis of TNF-a in the visceral organs, including the brain, is correlated with a less marked biologic response to laparoscopic surgery.