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Assessment of Respiratory Function in Conscious Mice by Double-chamber Plethysmography
Published on: July 10, 2018
[The effect of leukotriene antagonist on the parameters of dose-response curve obtained after methacholine challenge
1Department of Internal Medicine, First Affiliated Hospital, WCUMS, Chengdu 610041, China.
Objective:
To investigate the effect of leukotriene antagonist (zafirlucast) on the parameters of dose-response curve (DRC) obtained after methacholine challenge test.
Methods:
A therapy trial was conducted with the use of zafirlucast in 20 cases of cough variant asthma (CVA) and 20 cases of asthma. Placebo was used in 4 cases of CVA and 10 cases of asthma for comparison with the two therapy groups respectively. Before and after the zafirlucast treatment a series of parameters of DRC were obtained after the methacholine challenge test and were calculated. These included the response threshold (PC35sGaw), the dose-response slope (DRS), the ratio of the area under the curve to the logarithm of the maximal concentration (AUC/1 g[Cmax]), and the maximal response.
Results:
Zafirlucast significantly increased the PC35sGaw in the CVA and asthma groups. It conspicuously decreased all the parameters of DRS and AUC/1 g[Cmax] except for maximal response in the cases of CVA, and it had no significant effects on all the parameters of DRS and AUC/1 g[Cmax] except for PC35sGaw in the cases of asthma.
Conclusion:
Short-term use of Zafirlucast in asthmatic patients could improve the parameters of dose-response curve obtained after the methacholine challenge test.
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