Abstract: 【Abstract】 Objective To explore the effects of brain-derived neurotrophic factor (BDNF) antibody to block lung injury and interleukin-1β (IL-1β) expression in the rats with brain ischemia. Methods Thirty nine SD rats were divided into sham group, brain ischemia lung injury (BILI) group, and BDNF antibody treated group. Inflammatory lung injury was induced by brain ischemia in the later two groups, and BDNF antibody was given through intraperitoneal injection to the rats for 3 days in BDNF antibody group. Lung tissue samples were harvested from the rats in each group at the 3rd day after brain ischemia. Lung edema degree was evaluated by HE staining. The protein expressions of IL-1β in the lung tissues were measured by the methods of immunohistochemistry (n=5) and Western blot (n=8). Results The increased immunostaining of IL-1β were found in the lung tissue at 3 days after brain ischemia, which indicated the upregulated expression of IL-1β protein in the lung injury induced by cerebral ischemia. The block of BDNF antibody resulted in a significant decrease of IL-1β expression, as well as the decrease of lung edema. Conclusion BDNF, as a crucial factor, could regulate airway inflammation injury in brain ischemia rats via activating IL-1β expression.