RESUMEN
<p><b>OBJECTIVE</b>To observe the preventive and therapeutic effect of tanshinone (TA) on artery restenosis in the rat carotid injury model and explor the mechanism.</p><p><b>METHOD</b>Male SD rats were randomly divided into model control group, and low dose, moderate dose and high dose TA groups. Each group had 10 rats. The rats in the high, moderate and low dose groups were respectively fed with TA 120, 40,13.3 mg x kg(-1) x d(-1) by gast rogavage; the rats in the model control group were fed with the same volume solvent. Two days later, the rat's right carotid artery was injuried by balloon dilatation to induce intimal thickening for establishing the restenosis model. After 2 weeks of treatment, the artery was harvested and stained by hematoxylin-elsin (HE) and immunohistochemistry of PCNA, NF-kappaB and iNOS. The morphological changes were checked under microscope. The area of the intimal and medial layer of the vessels, and their ratios were analyzed with image analysis software. The expression level of PCNA, NF-kappaB and iNOS were used as the positive index.</p><p><b>RESULT</b>The intimal area and intima-to-media ratio of the injuried artery increased obviously, suggesting the model was successful. Compared with the model group, TA significantly decreased the intimal area and intima-to-media ratio (P < 0.05), and also decreased the positive index of PCNA and the positive ratio of NF-kappaB and iNOS (P < 0.05).</p><p><b>CONCLUSION</b>TA can effectively inhibit intimal thickening and inflammation. This result suggestes that TA may play a positive role in the prevention of restenosis after PTCA.</p>