RESUMO
<p><b>OBJECTIVE</b>To study the protective effects of Ginkgo biloba extract (EGb) on the lung injury of dogs undergoing hypothermic cardiopulmonary bypass (CPB).</p><p><b>METHODS</b>Fourteen healthy hybrid dogs were randomly divided into the control group and the EGb group, 7 in each group. EGb (8 mg/kg) was intravenously dripped to dogs in the EGb group before thoracotomy after anesthesia, while equal volume of normal saline was intravenously dripped to those in the control group. The lung tissue was collected after 60-min CPB and 120-min recovery of heart beat. The lung tissues were collected to detect the wet weight-dry weight ratio and the permeability. The contents of malondialdehyde (MDA), the activities of myeloperoxidase (MPO) and total superoxide dismutase (T-SOD) in the lung tissues were detected by biochemical assay. The levels of IL-1beta, IL-8, tumor necrosis factor alpha (TNF-alpha), platelet activating factor (PAF) in the lung tissue were detected by enzyme linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>Compared with the control group, the wet weight-dry weight ratio was reduced and the permeability of the lung tissue decreased (P < 0.05), the MDA content was reduced, the activity of MPO decreased, and the activity of T-SOD increased (P < 0.05), and the levels of IL-1beta, IL-8, and PAF obviously decreased (P < 0.05).</p><p><b>CONCLUSIONS</b>EGb showed better protective effects on the lung injury of dogs undergoing hypothermic CPB. Its possible mechanisms might be associated with alleviating ischemia-reperfusion injury of in vitro circulation and systemic inflammatory response.</p>