Table 3. Inhibitory effects and IC₅₀ of peptide binding rhNRP-1 (chemiluminescence detection).

Compound	AA2–AA3 fragment	100 μM	50 μM	Inhibition of NRP-1/VEGF-A165 binding [%]					IC50 [μM]
				25 μM	10 μM	5 μM	2.5 μM	1 μM
1	n/a	58.2 ± 1.2	43.8 ± 1.3	35.0 ± 2.6	30.8 ± 3.8	—	—	—	84.1 ± 2.9 a
2	Pro–Pro	77.0 ± 1.0	67.9 ± 1.4	54.1 ± 1.0	37.1 ± 1.0	—	—	—	20.9 ± 0.3 b
3	Dab–Pro	79.8 ± 0.8	76.6 ± 0.9	70.4 ± 0.5	58.6 ± 1.4	43.7 ± 0.7	31.4 ± 0.5	13.8 ± 0.3	8.9 ± 0.8 c
4	Pro–Ala	70.7 ± 0.5	62.1 ± 0.3	50.3 ± 1.0	35.5 ± 2.0	—	—	—	23.4 ± 7.9 d

^alog IC₅₀ = –3.08 ± 1.18.

^blog IC₅₀ = –4.68 ± 0.04.

^clog IC₅₀ = –5.05 ± 0.13.

^dlog IC₅₀ = –4.63 ± 0.12; R² ranged between 0.96–0.99. Results are presented as the mean ± SEM. n/a means not applicable.