EC50 or ED50 values and the relative potency of PAR-2-activating peptides in distinct assay systems
EC50 (micromolar concentration) and ED50 (micromoles per kilogram) were calculated in each assay system. The relative potency shown in parentheses was calculated by an equation, (EC50 or ED50 of SLIGKV-OH)/(EC50 or ED50 of each peptide).
EC50 (Relative Potency) | ED50 (Relative Potency) Salivation | |||||||
|---|---|---|---|---|---|---|---|---|
| HCT-15 | NCTC2544-PAR-2 | SMA Relaxation | Ama (−) | Ama (+) | ||||
| SLIGKV-OH | 22.8 (1) | 0.54 (1) | 39.8 (1) | 32.9 (1) | 31.7 (1) | |||
| SLIGRL-OH | 7.87 (2.90) | 0.20 (2.70) | 16.8 (2.37) | 9.95 (3.31) | 7.86 (4.03) | |||
| SLIGKV-NH2 | 5.05 (4.51) | 0.075 (7.20) | 2.19 (18.1) | 11.4 (2.88) | 3.10 (10.2) | |||
| SLIGRL-NH2 | 3.13 (7.28) | 0.046 (11.7) | 1.68 (23.7) | 2.84 (11.6) | 0.250 (127) | |||
| 2f-LIGKV-OH | 1.68 (13.6) | 0.067 (8.06) | 1.00 (39.8) | 0.840 (39.2) | 0.690 (45.9) | |||
| 2f-LIGRL-OH | 1.21 (18.8) | 0.024 (22.5) | nd | nd | nd | |||
| 2f-LIGKV-NH2 | 0.318 (71.7) | 0.0076 (71.1) | 0.219 (181) | 0.070 (470) | 0.0600 (528) | |||
| 2f-LIGRL-NH2 | 0.253 (90.1) | 0.0050 (108) | 0.077 (517) | 0.0300 (1100) | 0.0400 (793) | |||
nd, not determined; SMA, rat superior mesenteric artery; Ama, amastatin.