ABSTRACT
Objective To investigate the effect of carbachol on local gut inflammation during entetal resuscitation of rats with bum shock. Method Thirty-eight Wistar rats were subjected to 35%TBSA full thickness scald injury, and enteral fluid was infused into animal intestines via duodenal stomas 30 minutes post bum. The animals were randomly divided into four groups: no resuscitation (Control, n = 8), enteral resuscitation using either a glucose electrolyte solution (GES, n = 10) or GES plus carbachol (60 μg·kg-1,GES/CAR, n = 10), or carbachol alone (CAR, n = 10) .The volumeof GES infusion was based on the Parkland formula (4 ml· 1% TB-SA-1·Kg-1) - All animals were sacrificed 4 hours post bum, and specimens of jejunal tissue were collected to determine the levels of tumor necrosis factor (TNF)-α, nitric oxide (NO), nitric oxide synthase (NOS) and myeloperoxidase (MPO). Serum assays for plasma diamine oxidase (DAO) activities were also performed. Results There were no statistical differences in the intestinal levels of NOS, NO, TNF-α and MPO, and plasma OAO activities, between the GES group and the control group. Compared to the GES group, the GES/CAR group showed significantly lowered levels of intestinal NOS (1.276 ±0.391 vs. 1.818 ±0.436, P＜0.05), NO (0.925 ±0.402 vs. 1.561 ±0.190, P ＜ 0.05, TNF-α (0.87±0.13 vs. 1.94±0.47, P ＜0.01) and MPO (0.465 ±0.092 vs. 0.832±0.214, P＜0.05),and reduction in plasma DAO activites (0.732±0.192 vs. 1.381 ±0.564, P ＜0.05). The CAR group also showed significantly lowered levels of intestinal NOS, NO, TNF-α and MPO and reduced plasma DAO activites, compared to the GES group. Conclusions Theses results suggest that carbachol significantly inhibits the release of proinflammatory mediator and attenuates local inflammation in gut during enteral fluid resuscitation of rats in rats with bum shock. We postulate that carbachol may exert its and-inflammatory effects via the cholinergic anti-inflammatory pathway.