ABSTRACT
Objective To study the effect and mechanism of down-regulating Silt2/Robo 1 signaling pathway on rabbit iliac artery after angioplasty restenosis. Methods The 30 male New Zealand white rabbits were divided randomly into 3 groups , namely the blank group , the control group , and the experimental group , 10 rabbits in each group. Hign-fat feeding , the rabbits were produced endothelial denudation of iliac artery stenosis model. Another 4 weeks of feeding , percutaneous balloon angioplasty was performed. Then R5 antibody was injected into the abdominal cavity. After 4 weeks of feeding ,angiography again. The results of angiography was analysied by image workstation. The concentrations of Slit2 and Robo1 was detected by ELISA. The iliac artery tissue examined by HE staining. Results The rabbit iliac artery after angioplasty restenosis animal model was set up successfully. Compared with the control group and the experimental group , the serum concentration of Slit2 and Robo1 were significantly higher (P < 0.01) than the blank group. But in the experimental group, the Slit2 and Robo1 serum concentrations were significantly lower than those in the control group (P < 0.05) after R5 antibody intervention. The area ratio stenosis and diameter stenosis rate of iliac artery were reduced that confirmed by angiography. Conclusion The expression of Slit2/Robo1 was significantly higher in the rabbit model of vascular restenosis. R5 antibody can effectively inhibit the expression of Slit2/Robo1. Down regulation of Slit2/Robo1 signaling pathway in the treatment of restenosis after angioplasty in rabbits.
ABSTRACT
Objective To investigate the effects of CD147/MMP-9 pathway on early left ventricular remodeling Methods 30 healthy eight-week male SHR were divided into 3 groups (n = 10 for each group). SHR group received tail vein injections of normal saline weekly; CD147 group received CD147 of 600 ng·kg-1 weekly; and CD147+DOX group received CD147 of 600 ng/kg weekly and intragastric administration of DOX ( doxycycline ) of 30 mg/kg daily . 10 healthy eight-week male Wistar-Kyoto rats (WKY group) were treated as SHR group. Echocardiography, myocardial sections microscopy examination (HE and VG stain), and Western blot (for assessing levels of MMP-9, TIMP-1, CD147, and collagen I and Ⅲin myocardial tissues) were performed on day 56. Left ventricular weight index (LVWI)was measured and calculated. Collagen volume fractions (CVF) were obtained by image analysis. Results As compared with WKY group , levels of CD147 , MMP-9 , and MMP-9/TIMP-1 were lower but TIMP-1 and collagenⅠand Ⅲ were significantly higher in SHR group. The abundance of CD147 and MMP-9 protein and the ratio of MMP-9/TIMP-1 were obviously increased in CD147 group than in SHR group (P < 0.05). Levels of CD147, MMP-9, and MMP-9/TIMP-1 did no differ between CD147+DOX group and CD147 group. LVWI and contents of collagenⅠand Ⅲ were obviously declined in CD147 group as compare with SHR group. Cardiomyocyte hypertrophy , partial myocardial fibre rupture , myocyte dissolution and fuzzy myocardial fibre boundaries , more abundant of collagen fibers, and higher CVF were found in SHR group. Cardiac fibrosis was significantly improved after CD147 intervention, but the action was suppressed as DOX was administrated simultaneously. Conclusions Early ventricular remodeling may be involved in the inhibition of CD147/MMP-9 pathway in SHR. Input of CD147 to upregulate the pathway can improve the remodeling.
ABSTRACT
<p><b>OBJECTIVE</b>To assess the feasibility and safety of using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum.</p><p><b>METHODS</b>A total of 136 patients undergoing artificial heart pacemaker implantation with active fixation pacing leads were randomized into two groups to receive conventional right ventricular outflow tract pacing (CRVOTP) or modified right ventricular outflow tract pacing (MRVOTP). The electrode lead wire core was modeled in a double-curved three-dimensional shape in CRVOTP group and in a J-shaped bend in MRVOTP group before fixation at the right ventricular outflow tract septum.</p><p><b>RESULTS</b>Right ventricular outflow tract septum pacing was achieved successfully in all the patients. None of patients experienced serious complications. No significant differences were found between the two groups in the number of times of electrode fixation, pacing thresholds, impedance, R wave height or QRS wave width during the operation, but MRVOTP was associated with a reduced time of X -ray exposure and operation (P<0.05) due to the convenience in electrode modeling and in passing the leads through the tricuspid annulus and the direct access to the right ventricular outflow tract septum. Postoperative follow-up of the patients showed no incidence of active fixation pacing lead dislocation and comparable pacing thresholds of the ventricular electrodes, impedance, R wave height and QRS wave width between the two groups.</p><p><b>CONCLUTIONS</b>Using the modified active fixation pacing leads model to pace the right ventricular outflow tract septum can reduce the time of X -ray exposure and operation with a low probability of lead damage.</p>