Effects of intravascular irradiation plus drugs on restenosis following intravascular intervention therapy

Objective To evaluate the preventive effects of intravascular irradiation plus clopidogrel and simvastatin on restinosis, and to analyse their synergy. Methods Male New Zealand rabbit models with restenosis were developed. They were divided into 4 groups: only injuried group, intravascular irradiation group followed immediately by ionizing radiation using liquid  32P-filled balloon catheter, drug group, fed clopidogrel and simvastatin,and combined group given ionizing irradiation and fed clopidogel and simvastatin. At weeks 2, 4 and 8 after the balloon injury operation, the target vascular sections were cut and stained with HE, and analysis of photomicrograms using computer to estimate the vessl histomorphologic changes. ICAM-1, NF-κB and PCNA expression was detected by immunohistochemical technique. Results Intravascular irradiation treatment significantly inhibited neointimal proliferation. Intravascular irradiation group compared with injured group:① Lumen area(LA), intimal thickness(IT), intimal area(IA), and IT/MT and IA/MA ratios of rapamycin group were significantly reduced (P0.05) with dose-dependent decrease(P0.05); ②PCNA, NF-κB and ICAM-1 expression was significantly reduced(P0.05) with dose-dependent decrease(P0.05). Other three group compared with combined group:① LA, IT, IA, IT/MT and IA/MA of the combined group were significantly reduced (P0.05) with dose-dependent decrease(P0.05); ②PCNA, NF-κB and ICAM-1 expression was significantly reduced(P0.05) with dose-dependent decrease(P0.05). Conclusion ①Clopidogrel and simvastatin can prevent restenosis.②Intravascular irradiation can prevent restenosis.③The effect of intravascular irradiation with clopidogrel and simvastatin is better than only intravascular irradiation