INHIBITORY EFFECT OF A SINGLE LOCAL PROBUCOL ADMINISTRATION ON NEOINTIMAL FORMATION IN BALLOON-INJURED RAT CAROTID-ARTERY

The aim of this study was to determine whether a single local probucol administration could suppress neointimal formation in balloon-injured rat carotid artery. Rats were divided into four groups: (i) rats rece iving no probucol (control group); (ii) rats receiving topical applica tion of 50 mg probucol at the time of ballooning (p-top group); (iii) rats fed chow containing 1% probucol (p-fed group); (iv) rats receivin g both topical application of 50 mg probucol and chow containing 1% pr obucol (p-top/fed group). Although serum total cholesterol levels did not significantly differ between the control and the p-top groups at t wo weeks after balloon injury, the p-top group had a smaller intimal/m edial ratio or intimal area than the control group (0.97 +/- O.11 vs. 0.53 +/- 0.08 or 0.15 +/- 0.02 mm(2) vs. 0.08 +/- 0.02 mm(2) respectiv ely, P < 0.01). Neointimal formation was suppressed to a similar exten t in the p-fed group, in which serum total cholesterol level was appro ximately 40% lower than that in the control group, Thus, a single loca l delivery of probucol can suppress neointimal formation in balloon-in jured rat carotid artery without altering serum lipid level.