Protective Effect Of PHCD On Rats With Hydrochloric Acid-induced Acute Lung Injury

Objective To investigate the effect of Penehyclidine hydrochloride(PHCD) on Caspase-3and Apoptotic index(AI) during hydrochloric acid of acute lung injury (ALI) in rats, and to investigate its mechanism.Methods Hydrochloric acid was used to reproduce the model of ALI in rats.Twenty-four adult SD rats were randomly divided into three groups(n=8each):control group(group N); injured group(group H); treated group(group P); N group injected in trachea saline(ph=5.3)1.2ml/kg, H group injected in trachea hydrochloric acid (PH=1.251.2ml/kg)in rats,P group injected in trachea hydrochloric acid in rats before30min tail intravenous PHC (1mg/ml)2ml/kg.The same method, N group tail vein into saline(ph=5.3)2ml/kg,Three groups of animals die from made timing starts,4hours at the time to be put to death. Observe the arterial blood gas, apoptosis was detemined by TUNEL test (Teminal deoxynucleotidyl transferase-mediated dUTP nick end labeling), the activity of Caspase-3by immunohistochemistry and the lung tissue pathology change by light microscopy after4h of hydrochloric acid injection.Results The animal model of lung injury (ALI) was successfully replicated by Hydrochloric acid. After ALI, these rats showed tachypnea,lips cyanosis and with significant wheezing sound. During the dissection after4h,the injured group rats’thoracic cavities, there are lots of bloody secretions,the naked eye can observe lung tissue edema most congestion, inferior lobe of right lung injure seriously. Hydrochloric acid significantly increased PaCO2,the lung cell apoptosis rate, and the expression of caspase-3and decreased PaO2in the lung as compared with control group. PHCD before Hydrochloric acid significantly attenuated the Hydrochloric acid-induced changes. Electron microscopy showed that PHCD before Hydrochloric acid significantly ameliorated the Hydrochloric acid-induced histological damages.Conclusions First, The Caspase-3and the AI of the rats of injury of lungs increased during the apoptosis period, and meanwhile the PaO2decreased,the PaCO2increased. The rise of the products of apoptosis indicated that tissues were in higher level of the state of apoptosis. Second, Preteatment with PHCD before Hydrochloric acid can attenuate Hydrochloric acid-induced acute lung injury though inhibition of caspase-3activation and reduced the lung cell apoptosis rate.