Chronic obstructive pulmonary disease is a major clinical disorder usually associated with cigarette smoking. A central feature of chronic obstructive pulmonary disease is inflammation coexisting with an abnormal protease/anti-protease balance, leading to apoptosis and elastolysis. In anin vitro study of rat lung alveolar L2 cells, cigarette smoke extract (CSE) induced apoptotic cell death. Expo-sure of L2 cells to CSE at a concentration of resulted in a 50% increase of caspase-3 and matrix met-alloproteinase (MMP) activities. Specific inhibitors for caspases and MMPs attenuated the cytotoxicity of CSE. RT-PCR amplification identified VPAC2 receptors in L2 cells. .
