OBJECTIVETo observe Modified Zhisou Powder (MZP) on the lung function of chronic obstructive pulmonary disease (COPD) model rats of northwest China cold dryness syndrome (NCCDS).

METHODSTotally 90 male Wistar rats were randomly divided into three groups, i.e., the normal control group (n =20), the COPD model group (n =35), and the COPD of NCCDS group (n =35). The COPD model was established by tracheal dripping porcine pancreatic elastase (PEE) in combination with fumigation for 90 days. The COPD of NCCDS model was set up by tracheal dripping PEE +fumigation + cold and dry environmental stress for 90 days. Then rats in the COPD of NCCDS were randomly divided into the MZP intervention group (n =11 )and the normal saline intervention group (n =10).All intervention lasted for 15 successive days. The lung function was detected using Small Animal Lung Function Device at day 90 and day 105. And the lung pathology was also observed.

RESULTSLittle amount of sputum sound could be heard in the airway of the COPD model group and the COPD of NCCDS group. Pathological section showed alveolar ectasia, narrowed and broken alveolar septa, forming larger capsular space with infiltration of inflammatory cells. Rats in the COPD of NCCDS group showed chills, increased amount of drinking water, and loose stool. MZP could improve their symptoms. As for lung function test, compared with the normal control group, Te increased in the COPD model group (P <0.01), and EF50 decreased (P<0.05). PEF and EF50 decreased (P <0.01), Ti and Te increased (P <0.01, P <0.05) in the COPD of NCCDS group. Compared with the normal saline intervention group, PEF and EF50 increased (P < 0.01), Ti and Te decreased (P <0.01) in the MZP intervention group.

CONCLUSIONMZP could improve the symptoms of COPD rats of NCCDS, and delay the velocity of decreased lung function.