Table 2.
Competition-binding parameters of BODIPY®-labelled and native peptides of the NPY family in various NPY Y2 receptor assays
| Y2 HEK293-transfected cells | Rat brain [125I]PYY(3–36) | |
|---|---|---|
| Competitors | Ki (nM) | Ki (nM) |
| NPY | 3.8±1.6 (3)a | 2.9±1.0 (5) |
| BODIPY®TMR-NPY | 10±4 (3)* | 16±6 (4)* |
| [Leu31, Pro34]NPY | >1000 (3) | 200±45 (5) |
| BODIPY®TMR-[Leu31, Pro34]NPY | >1000 (3) | >1000 (3) |
| [Leu31, Pro34]PYY | 650±110 (3) | 165±30 (5) |
| BODIPY®FL-[Leu31, Pro34]PYY | >1000 (3) | >1000 (3) |
| PYY(3–36) | 0.6±0.2 (3) | 1.2±0.3 (5) |
| BODIPY®FL-PYY(3–36) | 10±3 (3)* | 17±5 (4)* |
| hPP | >1000 (3) | >1000 (3) |
| BODIPY®FL-hPP | >1000 (3) | >1000 (2) |
| [hPP(1–17), Ala31, Aib32]NPY | >1000 (3) | >1000 (3) |
| BODIPY®TMR-[hPP(1–17), Ala31, Aib32]NPY | >1000 (3) | >1000 (2) |
| [cPP(1–7), NPY(19–23), Ala31, Aib32, Gln34]hPP | >1000 (3) | >1000 (3) |
| BODIPY®TMR-[cPP(1–7), NPY(19–23), Ala31, Aib32, Gln34]hPP | >1000 (3) | >1000 (2) |
Data are the mean±s.e.m. of two to five determinations, each performed in triplicate.
a
Number in parenthesis represents the number of determinations. Ki represents the concentration of competitor needed to inhibit 50% specifically bound [125I]PYY(3–36).
*
P<0.05, fluorescent vs nonfluorescent peptide.