Protective effect of raloxifene on lung function after acute lung injury in rats / 中华创伤杂志

ABSTRACT

Objective To evalhate the protective effect of oral raloxifene on lung function after acute lung injury (ALI) in rats. Methods Thirty male adult Sprague-Dawley rats were used and divided into three groups LPS raloxifene hydrochloric acid. group before secondary impact ( Group A, n = 10 ), LPS raloxifene hydrochloric acid group after secondary impact ( Group B, n = 10) and control group ( n = 10). All the rats were injected intraperitoneally with 5 mg/kg LPS. Raloxifene (30 mg/kg) was orally administered one hour before LPS injection and 14 hours after LPS injection in Groups A and B. The con-trol group remained free. All the animals were anesthetized by intraperitoneal injection of pentobarbital so-dium at 40 mg/kg and the femoral artery was cannulated 16 hours after LPS injection to measure the mean arterial pressure (MAP). All the rats received a direct intratracheal injection of hydrochloric acid ( pH = 1.2, 0.5 ml/kg). Before injection of hydrochloric acid and at 0. 5,1.5 and 4 hours after injection of hy-drochloric acid, the blood gas was measured. Fifteen rats ( five from each group) underwent a micro posi-tron emission tomography ( [18F] FDG microPET) scan of the thorax four hours after hydrochloric acid in-stillation. Then, the lung tissue was collected for histopathological examination. Results The Group B showed better pulmonary gas exchange and more stable MAP compared to the control group. The [18F] fluorodeoxyglueose uptake and histological lung injury score were 9. 01 ± 1.58 and 12.6 ± 0.97 respec-tively in Group B, which were higher than 4. 67 ± 1.33 and 9. 01 ± 1.58 respectively in control group (P < 0. 01 ). Conclusions Raloxifene exerts significant protective effect on lung function after ALI. [18F] FDG microPET is a useful method to evaluate the inflammatory reaction during ALI.