Abstract: Objective To observe the effect of aerosolized lidocaine inhalation on expression of HSP70 and NF-κB in lung of asthma rat model. Methods Thirty two Wistar rats were randomly assigned to four groups (n = 8 each): control group (group A), asthma model group (group B), dexamethasone group (group C) and lidocaine group (group D). The rats in group B were sensitized by injection of ovalbumin (OA) together with aluminum hydroxide as adjuvants, followed by aerosolized OA challenge two weeks later. The rats in group C and D were sensitized with OA as group B, but exposed to 0.02% aerosol of dexamethasone and 0.04% aerosol of lidocaine 20 ml respectively. In group A saline was used instead of OA. In 24 hours after the last challenge, the lungs were removed for microscopic examination, determination of W/D lung weight radio, the expression of HSP70 and NF-κB was studied immunohistochemically. Results ①The W/D lung weight radio were 4.08±0.16, 3.54±0.10 and 3.66±0.12 respectively in group B, C, D, more than the group A with 3.30±0.12. ②The pulmonary expression of HSP70 were 0.210±0.018, 0.138±0.010 and 0.154±0.012 respectively in group B, C, D, higher than the group A with 0.049±0.015. ③The pulmonary expression of NF-κB were 0.199±0.029, 0.132±0.010 and 0.150±0.017 respectively in group B, C, D, higher than the group A with 0.056±0.022. ④Compared with the group B, the W/D lung weight radio and pulmonary expression of HSP70 and NF-κB in group C and D were significantly down-regulated. In animals with asthma the bronchial walls were significantly thicker with inflammatory cell infiltration. Dexamethasone or lidocaine aerosolized inhalation significantly attenuated the pathologic changes induced by asthma. Conclusion Aerosolized lidocaine inhalation has a protective effect on airway inflammation and histology damages resulting from aeroallergen challenge in the asthma model of Wistar rats.
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