Abstract: The aim of the research is to investigate the antitussive and expectorant effects and mechanism of Pinellia ternate and provide references in clarifying the main position of Baoning Banxia granules.Cough induced by stiff ammonia solution and phenol red excretion method were observed to evaluate the antitussive and expectorant effects of Pinellia ternata.The cough model induced by capsaicin was used to record the cough times and determine the content of P substance by ELISA to explore the antitussive mechanism.We found,compared with the CMC model group,Pinellia ternate 0.69 and 1.38 g/kg prolonged the cough latency,significantly decreased the number of cough in 3 min (P<0.05,P<0.01),and Pinellia ternate 1.38 g/kg significantly also decreased the number of cough in 2 min (P<0.05).Three doses of Pinellia ternata (0.69,1.38 and 2.76 g/kg) could significantly increase the excretion of phenolic red in mice (P<0.05,P<0.01).Pinellia ternata significantly decreased P substance in the cough mice with capsaicin (P<0.05),but had no significant effect on the cough times of mice treated with naloxone.Pinellia ternata could improve the asthma recovery time at the model animal (P<0.05),and had no effect on behavior score and asthmatic latent period (P>0.05).Pinellia ternata could not increase tracheal tension induced by antihistamine,suggesting that there was no blocking effect on H1 receptor (P>0.05).In conclusion,Pinellia ternata had antitussive and expectorant effects,and its antitussive mechanism is related to the inhibition of substance P release,which might play an antitussive effect through peripheral.The mechanism of expectorant,antiasthmatic effects needs further exploration.

Key words: Pinellia ternata, antiussive, expectorant, antiasthmatic