Establishment of a Rat Model of Pulmonary Infection due to Pseudomonas aeruginosa

OBJECTIVE To establish a rat model of pulmonary infection by inoculating Pseudomonas aeruginosa to Sprague-Dawley(SD) rats and evaluate it.METHODS Two hundred SD rats were divided into 2 groups: the P.aeruginosa group and the control group,P.aeruginosa was embedded in minute seaweed alginate beads by an ejection set with an acuminate hole.Then the beads were inoculated into the rats′ lung through tracheal intubation.RESULTS The bacteriological values: P.aeruginosa was detected from rats of infected groups.Bacterial number was higher than 105CFU/g 3 and 7 days after infection and higher than 103CFU/g 14 and 28 days after infection.The pathological changes showed: 3 and 7 days after infection,lung abscess,edema,and consolidation could be seen from lungs of infected groups.At optical microscopy,alginateP.aeruginosa caused a pronounced inflammatory reaction with polymorphonuclear cells surrounding a bead.Fourteen and 28 days after infection,fibrinous adhesions and granulomas became the major pathological changes.CONCLUSIONS The animal model of pulmonary infection can be established by inoculating P.aeruginosa embedded in minute seaweed alginate beads made by an ejection set with an acuminate hole to SD rats.