The Role Of Leukemia Inhibitory Factor In The Airway Neurogenic Inflammation Of Asthmatic Rats

Objective: To study the expression of leukemia inhibitory factor in the lungs and dorsal root ganglia of asthmatic rats, and to explore the role of leukemia inhibitory factor in the airway neurogenic inflammation. Methods: 18 Sprague-Dawley rats were randomly divided into four groups: control group(group N, n=4), asthma group(group A0, n=4), asthma + anti-LIF low concentration group (group A1, n=5) and asthma + anti-LIF high concentration group(group A2, n=5). The rats in group A0, A1 and A2 were given intraperitoneally injection of ovalbumin and aluminum hydroxide, and two weeks later received nebulization aspiration of 1% ovalbumin solution. 2μg/kg and 10μg/kg Anti-LIF rabbit antibody was respectively injected intraperitoneally into rats of group A1 and A2, at one hour before nebulization aspiration of 1% ovalbumin solution. The localiaztions of NGF, LIF, SP, pERK1/2 and pSTAT3 in lung tissues and dorsal root ganglia were detected by immunohistochemistry and the intensities of immunoreactivity were analyzed by image analysis system and converted into positive unit(PU).Results: NGF, LIF, SP, pERK1/2 and pSTAT3 immunoreactivities were observed primarily in bronchial epithelial cells and neurons of dorsal root ganglia. In bronchial epithelial cells of group N, A0, A1 and A2, the PU value for NGF were 12. 2 ± 2.3, 14.3±2. 4, 13.6±3. 4 and 11.4 ± 2.3 respectively, for LIF were 9. 9 ± 2.7, 15.8 ± 3.8, 15. 6±2. 2 and 12. 2 ± 3. 1 respectively, for SP were 33. 7 ± 5. 3, 42.9±8.3, 38. 4±5. 3 and 35. 8±6. 0 respectively, for pERK 1/2 were 10. 1±3. 2, 12.9 ± 2.9, 11. 9 ± 2.3 and 10.2 ± 2.0 respectively, and for pSTAT3 were 9.9±1.8, 14.4 ± 2.4, 12. 9±4. 6...