The model was established in male rabbits with experimental
atherosclerosis, which was induced by diet
cholesterol (0.5 g per day for 8 weeks), by means of
intravenous injection of one unit of
pituitrin (P.P.). To evaluate the effects of
aspirin,
heparin and
viper venom (VV) on this model, 26 male rabbits were divided randomly into four groups: group A (GA) as control, group B (GB) treated with
heparin (10mg, i.v.), group C (GC) with VV (0.08
arginine esterase activity units), group D (GD) with both
heparin and VV.
Aspirin (30 mg) was given orally before experiment. The results showed that the rate of
coronary thrombosis was 11.26% in GA, 8.10% in GB, 9.17% in GC, and 7.56% in GD respectively. The difference between each of three treated groups and the control one was significant (P < 0.005, 0.05, 0.001, respectively). Such a difference can also be found between GA and that without oral
aspirin (11.26% vs 16.39%, P < 0.001). The beneficial effects of
heparin and VV may be due to their inhibitory effects on different steps of
thrombosis, i.e.,
heparin can prolong the coagulation time, and VV can inhibit platelet aggregation and decrease the concentration of plasma
fibrinogen. It is concluded that
heparin,
viper venom, and especially their combination would be useful in the treatment of human
acute coronary syndromes.