The release of vasoactive substances, 6-keto-prostaglandin F1α (stable marker of prostaglandin I2), endothelin-1, and nitric oxide, was significantly influenced by the incubation with the peptide VPL compared with control cells (P < 0.05), as shown in Table 1.
Table 1 Relative concentrations of vasoactive substances per milligram of cell protein in cell medium of human aortic endothelial cells treated with various di- and tripeptides compared to untreated cells a.
Peptides
| Concentration | Relative concentration of vasoactive substances (% of control)
| TXB2 (control = 100 ± 11)
| 6-keto-PGF1α (control = 105 ± 15)
| ET-1 (control = 100 ± 19)
| NO (control = 100 ± 29)
| H-Val-Pro-Leu-OH
| 100 nM | 101 ± 30
| 124 ± 10*
| 184 ± 21*
| 195 ± 38* | 50 μM | 108 ± 49
| 135 ± 42
| 160 ± 46*
| 198 ± 49*
| a Results are means ± SD for n=6. * Different from untreated cells; P < 0.05. | |