ABSTRACT
ObjectiveTo establish a mouse model of basilar artery dolichoectasia （BAD） and explore the mechanism of modified Tongqiao Huoxuetang （JTQHX） in regulating BAD via phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt） pathway. MethodSixty C57/BL6 female mice were randomized into sham operation （injected with 10 U·mL-1 inactivate elastase）， model， atorvastatin calcium tablets （2.6 mg·kg·d-1）， and low- and high-dose （crude drug 3.4， 17 g·kg-1·d-1， respectively） JTQHX groups. The mouse model of BAD was established by injection with 10 U·mL-1 elastase. After 14 days of modeling， the sham operation group and model group were administrated with equal volumes of pure water by gavage， and other groups with corresponding drugs for 2 months. The levels of interleukin-6 （IL-6） and calpain （LpA） in the serum were measured by enzyme-linked immunosorbent assay （ELISA）. Verhoeff 's Van Gieson （EVG） staining was employed to observe the pathological changes of blood vessels. Terminal-deoxynucleotidyl transferase mediated nick end labeling （TUNEL） was employed to examine the apoptosis rate of vascular smooth muscle cells （VSMCs）. Image Pro Plus was used to observe and calculate the curvature index， elongation length， percentage increase in vessel diameter， and curvature angle of the basilar artery vessels in mice. Western blot was employed to determine the expression levels of PI3K and Akt in the vascular tissue. ResultCompared with the sham operation group， the model group showed lowered IL-6 level （P<0.01）， no significant change in LpA level， increased apoptosis of VSMCs （P<0.01）， and increased curvature index， elongation length， percentage increase in vessel diameter， and curvature angle （P<0.01）. Furthermore， the modeling up-regulated the protein levels of PI3K and Akt in blood vessels （P<0.01） and aggravated the destruction of the inner elastic layer， atrophy of the muscular layer， and hyaline changes in the connective tissue of the medial membrane of the basilar artery wall. Compared with the model group， 2 months of treatment with JTQHX elevated the IL-6 level （P<0.01）， reduced the apoptosis of VSMCs （P<0.01）， decreased the curvature index， elongation length， percentage increase in vessel diameter， and curvature angle （P<0.05， P<0.01）， and down-regulated the protein levels of PI3K and Akt in blood vessels （P<0.01）. In addition， the treatment alleviated the destruction of the inner elastic layer， atrophy of the muscular layer， and hyaline changes in the connective tissue of the medial membrane of the basilar artery wall. ConclusionJTQHX inhibits the elongation， expansion， and curvature of basilar artery vessels and alleviates the pathological changes by reducing the apoptosis of VSMCs and down-regulating the expression of PI3K/Akt pathway.