ABSTRACT
<p><b>OBJECTIVE</b>To explore the effect of Shenmai injection the expression of heme oxygenase-1 (HO-1) in rabbits with reperfusion injury after pulmonary ischemia.</p><p><b>METHOD</b>Single lung ischemia/reperfusion injury animal model was used in vivo. Twenty rabbits were randomly divided into two groups (n = 10, in each), pulmonary ischemia and reperfusion injury (PIRI) group and I-R + Shenmai injection group. The tissue slides were stained by in situ hybridization (ISH) for HO-1 to detect the expression of HO-1 in lung and to analyze the absorbance. Wet to dry ratio of lung tissue weight (W/D) and the injured alveoli rate (IAR) were measured at 180 minutes after lung reperfusion. Meanwhile the lung tissue slide was prepared for electron microscopic observation at 180 minutes after reperfusion.</p><p><b>RESULT</b>HO-1 expression was upregulated in two groups in the pulmonary endothelial cells, part of pulmonary vascular smooth muscle cells, extima of vessels and epithelial cells of airway, the absorbance was 0.148 +/- 0.013, 0.158 +/- 0.012, respectively. The Shenmai injection group showed higher absorbance than those of the IRI group (P < 0.01), lower W/D and IAR values than those of the IRI group (P < 0.01) significantly and lighter abnormal changes of the lung tissue in morphologically than those of the PIRI group.</p><p><b>CONCLUSION</b>Shenmai injection possesses notable protective effects on PIRI in rabbits by increasing the expression of HO-1 in lung.</p>