The Expression of MMP-9 and TIMP-1 in the Lung Tissues of Smoking Cessation Rat Model / 中国医师杂志

ABSTRACT

Objective To study the expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the lung tissues of smoking cessation rat model. Methods Fifty Wistar rats were randomly divided into the normal control rats which were exposed to room air for 4 and 6 months respectively(groups A and C), the smoking rats which were exposed to cigarette smoke for 4 and 6 month respectively(groups B and D), and the smoking cessation group which was exposed to room air for 2 months after 4 months' smoke exposure.The expressions of mRNA and proteins of MMP-9 and TIMP-1 in the lung tissues were detected by in situ hybridization and immunohistochemistry respectively. The collagen Ⅳ expression in the lung tissues was assessed by immunohistochemistry. Results Compared with groups A and C, the expression levels of MMP-9 and TIMP-1 in the lung tissues of groups B and D significantly elevated(P