This paper aims to observe the effect of modified Liu'an Decoction on the expression levels of key factors related to airway remodeling in lung tissue of guinea pigs with cough variant asthma (CVA),including transforming growth factor-β (TGF-β),matrix metalloproteinase-9 (MMP-9),notch receptor 1 (Notch1) of key genes in notch signaling pathway,δ-like typical notch ligand 1 (Delta1),zigzag typical notch ligand 1 (Jagged1),and hair division-associated enhancer 1 (Hes1),so as to investigate the mechanism of modified Liu'an Decoction in the treatment of CVA with airway remodeling.Methods:A total of 30 male guinea pigs were randomly divided into a normal group,a CVA model group,a montelukast sodium group,and low,medium,and high dose groups of modified Liu'an decoction,with five guinea pigs in each group.Except for the normal group,each group was sensitized by intraperitoneal injection of ovalbumin (OVA) and aluminum hydroxide [Al(OH)3],and then the CVA model was reproduced by OVA atomization.Each group was given a corresponding drug treatment.The pathological morphology of lung tissue was observed,and TGF-β and MMP-9 in lung tissue were measured.The mRNA levels of Notch1,Delta1,Jagged1,and Hes1 in lung tissue were detected.Results:1) The CVA model group had inflammatory cell infiltration,hyperemia and edema,basement membrane thickening,and partial alveolar collapse in lung tissue,and the treatment group had different degrees of reduction in inflammatory cell infiltration and hyperemia and edema. 2) The expression levels of TGF-β and MMP-9 in the CVA model group were higher than those in the normal group,and the expression levels of TGF-β and MMP-9 in the middle and high dose groups of modified Liu'an Decoction were lower than those in the CVA model group.3) Compared with the normal group,the mRNA expression of Notch1,Jagged1,and Hes1 in lung tissue of the CVA model group was increased,and the mRNA expression level of Delta1 was reduced; compared with the CVA model group,the mRNA of Notch1,Jagged1,and Hes1 was lower in the high dose group of modified Liu'an Decoction,and the mRNA expression of Delta1 in the medium and high dose groups of modified Liu'an Decoction was increased.Conclusion:Modified Liu'an Decoction may improve Th1/Th2 cell imbalance and reduce airway inflammation by regulating the expression of key genes of Notch,thereby regulating TGF-β and MMP-9 expression in lung tissue and improving airway remodeling.