[Anti-tussive and expectorant effects of Liangyuan Pipagao,a Chinese medicine]

OBJECTIVE: To evaluate the pharmacological effects of Liangyuan Pipagao on cough reflex and ciliary action. Liangyuan Pipagao is a compound preparation of traditional Chinese medicine. METHODS: Cough was induced by aerosol citric acid in guinea pigs and aerosol capsacin in mice. Excretion function of the airway in mice was determined by phenol red method. Ciliary movement function of frog esophagus was examined by a migration method of charcoal granules. RESULTS: Liangyuan Pipagao inhibited both the citric acid-induced cough in guinea pigs and capsacin-induced cough in mice. ID(50)value 2.64 g/kg (95%Cl1.12 approximately 6.19) and 11.40 g/kg (95%Cl5.76 approximately 22.58) respectively. Further, Liangyuan Pipagao increased phenol red excretion in mice airways and stimulated ciliary action of frog esophagusin a dose-dependent fashion. ED(50) value 7.70 g/kg (95%Cl 4.62 approximately 12.83) and EC(25) value 1.07 X 10(-4) (95% Cl 0.394 approximately 2.92x10(-4)) respectively. CONCLUSION: Liangyuan Pipagao a traditional Chinese medicine may have anti-tussive as well as expectorant actions.