Table 2.
Summary of agonist potencies (pEC50) for cAMP accumulation in response to agonists in neuron-enriched rat TG cultures and Cos7 cells transfected with rat or human CGRP receptor components
| Rat TG neurons1 | Rat CLR/RAMP1 | Rat CTR/RAMP1 | Human CLR/RAMP1 | Human CTR/RAMP1 | |
|---|---|---|---|---|---|
| αCGRP | 8.07 ± 0.09 (12) | 10.04 ± 0.05 (8) | 8.44 ± 0.23 (4) | 9.92 ± 0.06 (4) | 9.63 ± 0.12 (4) |
| rAmy | 7.69 ± 0.06 (6) | 7.66 ± 0.07 (6) *** | 8.37 ± 0.13 (4) | 7.40 ± 0.14 (4) *** | 9.46 ± 0.05 (4) |
| rAM | 6.68 ± 0.25 (3) ***,++ | 9.40 ± 0.17 (9) **,+++ | 7.20 ± 0.15 (4) **,++ | – | – |
| rCT | 7.25 ± 0.24 (4) ** | – | – | – | – |
Data represent mean ± SEM of n individual experiments. Comparisons were performed by one-way ANOVA followed by post-hoc multiple comparisons tests. TG, trigeminal ganglia; CGRP, calcitonin gene-related peptide; CLR, calcitonin receptor-like receptor; CTR, calcitonin receptor; RAMP, receptor activity-modifying protein; rAmy, rat amylin; rAM, rat adrenomedullin; rCT, rat calcitonin; –, not performed.
The amount of cAMP produced in TG neurons was as follows (Emax fmol/well [n]): rαCGRP 144.4 ± 24.7 (12); rAmy 108.3 ± 11.3 (6); rAM 123.5 ± 47.5 (3); rCT 179.8 ± 51.8 (4). There were no significant differences between these values.
P < 0.01
P < 0.001 versus αCGRP.
P < 0.01
P < 0.001 versus rAmy.