Abstract
Dai-Saiko-Toh is a traditional Chinese drug and has been noted to exhibit anti-atherogenesity. Following administration, aortas from fifty-one male New Zealand white (NZW) rabbits were studied to determine the drug's effect compared to controls, groups given feed containing 1.5% cholesterol and others. A group: Dai-Saiko-Toh administration (Tsumura, Tokyo, 1, 000mg/kg/day) for 3 or 6 months respectively after giving feed containing 1.5% cholesterol for 3 months, B group: simultaneous cholesterol containing feed and Dai-Saiko-Toh administration for 3 months, C group (control): normal diet feeding (vehicle, CR-1, Nihon-Kurea, Tokyo) for 3 or 6 months after giving feed containing 1.5% cholesterol for 3 months, D group: feed containing 1.5% cholesterol through the 3-month experimental period, and other groups. Body weight, levels of serum total cholesterol (TC), triglyceride (TG), cholestrol ester (CE), and others parameters were periodically monitored until sacrifice. Serum lipids and aortic tissue lipids were analysed, and the samples from the aortas were processed for pathomorphological analyses, including Surface Involvement (SI) and Atherosclerotic Index (AI) with the point counting method after Sudan IV staining.
Dai-Saiko-Toh administration for 6 months showed that serum levels of TC (71.4mg/dl, A group) tended to be lower than in the C group (128.0mg/dl), and serum TG (41.0mg/dl, A group) was significantly lower than in the C group (72.1mg/dl). The B group at termination of administration at 3 months exhibited trends of decreasing serum TC and TG compared to those of the D group. Dai-Saiko-Toh administration showed a significantly decreased value of CE in aortic tissue (215.3mg/g, A group) than that of the D group, but no significant decrease of CE compared with the C group (227.7mg/g). FC/PL ratio in the aortic intima-medial cells of the A group (3.55 at 6 months) was markedly lowered than in the C group (5.21). The value of AT in the A group (4.98 at 6m) was markedly decreased than in both the C (6.32) and D (7.09) groups. No significant differences were noted in SI among each group. Microscopically, the lesions tended to exhibit decreased foam cells, calcium deposition, and collagen synthesis with Dai-Saiko-Toh administration than in the C group.
Six-month administration of Dai-Saiko-Toh is less effective for 1.5% cholesterol induced-atherosclerosis in NZW rabbit aorta. However, Dai-Saiko-Toh may have a preventive effect or antiatherogenesity for initial atherosclerotic lesions by lowering serum TC and TG.
