RESULTS: Physic-chemical analysis revealed that the PSA contained 60.3% of total carbohydrate content, which was isolated from the A. Heterotropoides, mainly including glucose (74.05%), mannose (18.37%), arabinose (4.68%), galactose (1.54%). CS-enhanced cough in guinea pigs model was significantly inhibited after 14 days use of PSA at dosages of 200, 400, 800 mg/kg. 54.0%, 62.6% and 70.9% inhibition were found respectively at different dosages of PSA while 81.1% inhibition was found at a single dose of codeine phosphate (30 mg/kg) in compared with CS-exposure guinea pigs. Meanwhile, the CS-induced increase for the number of total cells and percentage of neutrophils in BALF, as well as the levels of TNF-α and IL-8 in lung tissue homogenate, were markedly decreased after treatment with PSA (200, 400, 800 mg/kg) for 14 days. The inflammation in lung tissue improved after treatment. The activities of SOD and GSH-Px in lung tissue were elevated, while the level of MDA was markedly decreased after oral administration of PSA.