Anti-asthmatic Effects Of The Extract Of Cortex Mori

Object: The total flavones extract of Cortex Mori (FCM) was extracted from the traditional Chinese medicine Cortex Mori. In this paper, we examined the antiasthmatic pharmacology effect of FCM. Methods and results:FCM could increase the latent period of asthma induced by inhaling histamine and acetylcholine in guinea-pigs. In the isolated guinea-pig tracheal sheet experiments, FCM relaxed the normal tone of isolated guinea-pig tracheal sheets, the -lgEC₅₀ (g/mL) for FCM was 3.96±0.65. The inhibitory effects of FCM on contraction induced by 10^-5mol/L histamine and acetylcholine were expressed as -lgIC₅₀(g/mL), which was 3.81±0.23 and 2.74±0.16, respectively; FCM could shift the concentration-response curves of histamine Acetylcholine and CaCl₂ to the rightward and the maximal effects were decreased, the inhibitory effects of FCM were expressed as pD₂'(g/mL) in a non-competitive manner, the pD₂'(g/mL) of FCM for histamine, Acetylcholine and CaCl₂ was 3.21±0.08, 2.87±0.38 and 3.44±0.18, respectively; In addition, it couldn't affect the contraction of phase I caused by acetylcholine, but could significantly inhibit the conrtraction of phase II caused by CaCl₂. FCM shortened the time of perfusate escaping from the lung surface in mice which was lengthened by Acetylcholine.Asthmatic guinea-pigs were developed by sensitization and challenging with ovalbumin. The inhibitory effects of FCM on asthma induced by ovalbumin were found in the experiment; and FCM markedly inhibited eosinophil(EOS) infiltration in lung tissue of asthmatic guinea-pigs, but we didn't find the effect of FCM on the concentration of 6-keto-PGF_1α in blood plasm of guinea-pigs. Moreover, FCM significantly inhibited the histamine-induced cutaneous capillary permeability, the paw edema caused by 5-HT and licking response induced by 4-aminopyridine in mice. FCM could significantly inhibit the ear swelling induced by xylene in mice and the paw edema caused by fresh egg white in rats.We also found that FCM could increase the latent period of cough and the number of coughs during a 3-min challenge induced by ammonia and sulfur dioxide in mice. The test of excretion of phenol red from bronchus in mice and the liquid secretion from the airway in rats showed that FCM could increase the airway mucus excretion.Conclusion: In summary, FCM could relax the tension of isolated guinea pig trachea muscles and antiasthmatic, and be equipped with the anti-allergic activities, antiinflammation, anti-tussive and removing phlegm effect.