Abstract: The fiftyfour SD rats were randomly divided into three groups:control (CK),general tobacco (GT) and new-type tobacco (NT).The COPD model was duplicated by exposing GT and NT rats to cigarette smoke until 56 days.Pathological changes in lung tissue were analyzed using H.E.,Masson and PAS staining at 14 d,28 d and 56 d,respectively.The obvious COPD features,such as inflammatory cells infiltration,airway remodeling and destroyed alveoli,were observed in the smoking rats.Lung injury scores were as follows:1.97±0.30 (CK group),23.93±0.73 (GT group) and 17.43±0.60 (NT group).Simultaneously,the levels of IL-8,TNF-α,MMP-9 and TIMP-1 in BALF and NF-κBP65 in lung tissue were detected by ELISA and immunohistochemical method.Compared to CK group,there was a significant increase in their levels in GT and NT groups,but the ratio of MMP-9/TIMP-1 was obviously decreased (P<0.05).With the extension of exposure time,there were obvious differences in the pathologic changes and abnormal inflammatory response between NT and GT group (P<0.05).The results indicated that the new-type tobacco exposure can slow the progression of COPD,which was probably related to the regulation of NF-κB pathway by some beneficial components.

Key words: new-type tobacco, Perilla frutescens (L.) Britt, rat, COPD