OBJECTIVETo study the analgesic, expectorant and antitussive effects of the compatible use of Aconiti Radix Cocta and Fritillaria cirrhosa or F. thunbergii with different matching ratio or dose in mice.

METHODThe two-factor, seven-level uniform design method was adopted to observe the analgesic, expectorant and antitussive effects of the oral administration with the two combined decoctions in rats, with frequency of body torsions induced by acetum, secretion of phenol red in tracheas and frequency of coughs as indexes. Significant matching proportions and doses were collected for verification.

RESULTThe effect on the frequency of body torsions: The combined decoctions could effectively reduce the frequency of body torsions. According to a regression analysis, Aconiti Radix Cocta and F. cirrhosa had the synergistic effect, which was maximized with a ratio of 1: 1. The 1: 1 combined decoction played the least role in reducing the frequency of body torsions with a total dose of more than 5 g x kg(-1). The effect on the secretion of phenol red in tracheas. The combined decoctions could effectively increase the secretion of phenol red in tracheas. According to a regression analysis, Aconiti Radix Cocta and F. thunbergii had the antagonism, which was maximized at the ratio of 1: 1, and minimized with a total dose of less than 10 g x kg(-1) and a ratio of 5: 1 between F. thunbergii and Aconiti Radix Cocta. The effect on the frequency of coughs. The combined decoctions could effectively reduce the frequency of coughs. According to a regression analysis, Aconiti Radix Cocta and F. cirrhosa had the antagonism, which was maximized at the ratio of more than 1: 5 and less than 10: 1. There was no interaction between Aconiti Radix Cocta and F. thunbergii. F. thunbergii could reduce the frequency of coughs, whereas Aconiti Radix Cocta showed no effect.

CONCLUSIONThe compatible application of Aconiti Radix Cocta and F. cirrhosa could enhance the analgesic effect of Aconiti Radix Cocta and reduce the expectorant and antitussive effects of F. cirrhosa, which vary according to different matching ratio and dose. The compatible application of Aconiti Radix Cocta and F. thunbergii shows no effect on the antitussive effect of F. thunbergii. This study provides experimental basis for in-depth studies on the combined effect of Aconiti Radix Cocta and Fritillaria--two of eighteen incompatible pairs.