ETOFIBRATE SUPPRESSES NEOINTIMA FORMATION OF THE BALLOONED COMMON CAROTID-ARTERY OF RATS

The inhibition of neointima formation by drugs is a major goal to prev ent restenosis following angioplasty. In the present study, the effect of etofibrate on blood lipids and vessel wall was investigated using a balloon injury rat model. Two weeks after ballooning the common caro tid artery neointima formation was quantified by morphometric measurem ent of the neointimal area and cellularity in vessel cross sections, a nd by fluorometric evaluation of the DNA content. Etofibrate (160 mg/k g/day) had no effect on plasma triglyceride levels, but reduced serum cholesterol by about 25%. The injury-induced increase of both the neoi ntimal area and the DNA-content was significantly inhibited by 47% (P < 0.005) and 34% (P < 0.05), respectively, in the drug-treated animals in comparison to the untreated control rats. The ratio of neointima a nd media was significantly (P < 0.001) reduced from 152.9 +/- 11.6% (c ontrols) to 82.84 +/- 12.59% in the etofibrate-treated group. The cell ularity (numerical profile and volume density of nuclei) in the neoint ima was similar in both groups. In conclusion, injury-induced neointim a formation is reduced in etofibrate-treated animals, which could be d ue to an inhibition of smooth muscle cell proliferation.