Experimental study of intravascular irradiation phus clopidogel and simvastatin on restenosis

AIM: To evaluate the preventive effects of intravascular irradiation phus clopidogel and simvastatin on restenosis,and to analyze their synergy.METHODS: Male New Zealand rabbit models of restenosis were developed.They were divided into 4 groups: the control group(without any treatment),intravascular irradiation group(ionizing radiation using liquid 32p-filled balloon catheter),drug group(clopidogel and simvastatin) and combination group(ionizing irradiation combined with clopidogel and simvastatin).At week 2,4 and 8 after the balloon injury operation,the target vascular sections were cut and stained with HE and histomorphologic changes of the vessels were carefully observed using computer analysis of photomicrograms.ICAM-1,NF-κB and PCNA expressions were detected by inmunohistochemical technique.RESULES: Intravascular irradiation treatment significantly inhibited neointimal proliferation.Compared with the control group: lumen area(LA),intimal thickness(IT),intimal area(IA),and IT/MT and IA/MA ratios of were significantly reduced in a dose-dependent manner(P0.05),and PCNA,NF-κB and ICAM-1 expression was also significantly reduced(P0.05).Compared with combination group: LA,IT,IA,IT/MT and IA/MA of the drug and irradiation group were significantly reduced in a dose-dependent manner(P0.05),and PCNA,NF-kB and ICAM-1 expressions were significantly lower(P0.05).CONCLUSION: Restenosis can be prevented either by clopidogrel and simvastatin or by intravascular irradiation,while intravascular irradiation combined with medication can exert much better synergistic effects.