Objective To investigate the changes of organic vascular permeability after severe burn in rats and determine if the selective bradykinin receptor 1 antagonist affects the vascular permeability.  Methods Ninety rats were divided into 5 groups: normal group (group N)

sham burn group (group S)

sham burn plus bradykinin receptor 1 antagonist (BR1A

des Arg

9

-Arg

8

-BK) group (group SI)

burn group (group B)

and burn plus BR1A group (group BI). BR1A (1 mol/kg) dissolved in normal saline to 1 mol/L was applied intravenously 20 min before the organ samples were taken. Evan’s blue (EB) was injected 10 min before preparation of myocardium from ve

ntricle

lung

kidney and intestinal tissues in dimethylformamide 0

3

6

12

24

48 h after burn. The content of dissolved EB was determined by UV spectrophotometer.  Results In comparison with group S

the content of EB in all organ tissues in the group B increased significantly

peaked 3 h after burn

kept at the high level in 24 h

and declined close to normal levels 48 h after burn. The content of EB was lower in all organ tissues in group BI than that in group B.  Conclusion The selective inhibitor of bradykinin B1 receptor apparently inhibits the increase of vasopermeability.