Table 1.
Effect of incubation of control platelets with IgG eluate from SCI plasma on the binding of [3H]PGE1 to prostacyclin receptors compared with prostanoid binding to SCI platelets
| Platelets | Treatment | PGE1/PGI2 receptors
|
|||
|---|---|---|---|---|---|
| High-affinity
|
Low-affinity
|
||||
| Kd1, nM | n1, sites per cell | Kd2, μM | n2, sites per cell | ||
| Control | Buffer | 9.1 ± 2.0 | 170 ± 32 | 1.9 ± 0.1 | 1,832 ± 232 |
| Control | IgG eluate from SCI | 7.2 ± 1.1 | 23 ± 8 | 1.6 ± 0.1 | 1,740 ± 161 |
| Control | IgG eluate from control | 8.9 ± 0.9 | 162 ± 34 | 1.8 ± 0.3 | 1,876 ± 138 |
| SCI | Buffer | 7.5 ± 1.5 | 40 ± 10 | 2.1 ± 0.3 | 1,970 ± 214 |
Platelets were isolated from either control (non-SCI) or SCI subjects and incubated with or without IgG eluates isolated from SCI or control plasma. The binding of [3H]PGE1 to platelets was determined and analyzed by Scatchard plot (10). Results are expressed as means ± SD of six experiments, each performed in triplicate.