Agonist activity of RFamide peptides at the hNPFF2 receptor
| Agonist activity [EC50 and efficacy relative to (1DMe)Y8Fa] was assessed as the ability of the compounds to stimulate [35S]GTPγS binding in membranes of CHO cells expressing human NPFF2 receptor (CHO-hNPFF2). Membranes (2 μg/sample) were incubated with [35S]GTPγS (0.07-0.15 nM) and 12 concentrations of ligands in the presence of 5 mM MgCl2, 1 μM GDP, and 20 mM NaCl. Data represent the mean ± S.E.M. from a minimum of three experiments. Representative curves for (1DMe)Y8Fa, NPFF, hRFRP-1, and hPrRP31 are shown in Fig. 1A. | ||||
|---|---|---|---|---|
| EC50 | Efficacy [Normalized against (1DMe)Y8Fa] | |||
| nM | ||||
| NPFF | 28 ± 11 | 79 ± 10 | ||
| (1DMe)Y8Fa | 23 ± 4 | 100 | ||
| rNPSF | 350 ± 40 | 110 ± 10 | ||
| FMRFamide | 89 ± 10 | 110 ± 20 | ||
| hPrRP31* | 240 ± 20 | 170 ± 10 | ||
| hPrRP20* | 170 ± 20 | 120 ± 10 | ||
| hPrRP24-31 | 200 ± 60 | 120 ± 10 | ||
| hRFRP-1 | 160 ± 30 | 92 ± 13 | ||
| hRFRP-3 | 620 ± 60 | 120 ± 10 | ||
↵* Significantly different from (1DMe)Y8Fa (p < 0.05).