Abstract:

Abstract:Objective To investigate the effect of 1 - methylhydantoin (1-MH) on asthma and cough animal model,and to clarify its mechanism preliminarily. Methods 50 Wistar rats with ovalbumin-induced asthma were randomly divided into model group,1-MH 20,40,and 80 mg/kg groups,positive control group (aminophylline,60 mg/kg),another 10 Wistar rats served as control group. The levels of interleukin-5 (IL-5), eosinophil chemotactic factor (Eotaxin) and eosinophil (EOS) count in bronchoalveolar lavage fluid (BALF)were measured in various groups. 40 guinea pigs of asthma were randomly divided into model group,1-MH 15,30,and 60 mg/kg groups,positive control group (aminophylline,50 mg/kg);the asthma incubation period of guinea pig was measured in various groups.The bronchus of 10 guinea pigs were selected and put in Krebs solution,and the antispasmodic percentages against histamine phosphate of 1-MH 0.25,0.50,and 1.00 g/L were recorded and calculated. 50 mice of cough were randomly divided into model group,1-MH 25,50,and 100 mg/kg groups,positive control group (codeine,50 mg/kg);the cough incubation period and the  number of cough in the mice were measured in various groups. 40 guinea pigs of cough were randomly divided into model group,1-MH 15，30，and 60 mg/kg groups,positive control group (codeine,20 mg/kg);the cough incubation period and  the number  of cough of  the guinea pigs  in various groups were measured. Results Compared with sensitized model control group,the levels of IL-5, Eotaxin and EOS count in BALF of the rats in 1-MH 40 mg/kg and 80 mg/kg groups were reduced(P<0.05 or P<0.01);compared with acetylcholine-induced asthma model control group,the asthma incubation period of guinea pig in 1-MH 30 mg/kg and 60 mg/kg groups was prolonged(P<0.05 or P<0.01);compared with blank control group,the antispasmodic percentages against histamine phosphate  in 1-MH 0.50 g/L and 1.00 g/L  groups were increased(P<0.01);compared with mouse cough model control group,the cough incubation period of the  mice was prolonged,the cough number of the  mice was decreased in 50 mg?kg-1 and 100 mg?kg-1 groups(P<0.05 or P<0.01);compared with guinea pig cough model control group，the cough incubation period of the  guinea pig was prolonged,the cough number of the guinea pig was decreased in 1-MH 30 mg/kg and 60 mg/kg groups (P<0.05 or P<0.01). Conclusion 1-MH has good antiasthmatic and antitussive effects,which may be related to inhibition of airway inflammation and relaxation of bronchial smooth muscle directly .

Key words: 1-methylhydantoin, ovalbumin, eosinophils, antiasthma, antitussive