Inhibitory effects of ozagrel on platelet aggregation and TXB2 production ex vivo in guinea pigs
Blood samples were collected 1 h after initiation of dosing. Ex vivo platelet aggregation was initiated with ADP (1 μ M) or collagen (1 μ g/ml). TXB2 was extracted from PRP aggregated with collagen or serum after whole blood coagulation. TXB2 production after collagen-induced platelet aggregation and whole blood coagulation were estimated as rate per 10 min and 1 h, respectively. Values are expressed as the mean ± S.E.M. of four to five animals. Numbers in parenthesis indicate percentage of inhibition of platelet aggregation and TXB2 production in comparison with control.
Dose (mg/kg + mg/kg/h for 1 h) | Platelet Aggregation | TXB2 Production | ||||
|---|---|---|---|---|---|---|
| ADP | Collagen | Collagen-Induced Platelet Aggregation | Whole Blood Coagulation | |||
| % | ng/ml | |||||
| Control | 58 ± 3 | 78 ± 1 | 33.1 ± 1.1 | 382.9 ± 50.2 | ||
| 3 + 10 | 59 ± 4 | 78 ± 1 | 34.2 ± 2.8 | 287.0 ± 23.1 | ||
| (−1.4) | (0.2) | (−3.4) | (25.0) | |||
| 30 + 100 | 62 ± 1 | 79 ± 1 | 14.7 ± 1.4** | 52.7 ± 5.0** | ||
|
| (−7.2) | (−0.8) | (55.6) | (86.2) | ||
↵** P < 0.01 versus control (one-way ANOVA followed by Dunnett's multiple comparison test). There were no significant differences in platelet aggregation among the groups.