Figure 6.

Activity of synthetic SLURP-1 on heteromeric human and rat neuronal nAChRs. (A) Representative ACh-evoked current traces mediated by hα3β4, hα4β2, hα9α10 and rα9α10 nAChRs in the presence of 10 µM sSLURP-1. (B) Bar graph of sSLURP-1 (10 μM) inhibition of ACh (EC₅₀)-evoked current mediated by hα3β2 (6 µM), α3β4 (300 µM), α4β2 (3 µM), α4β4 (6 µM) and α9α10 (6 µM) nAChRs and with ACh concentrations below or above the EC₅₀ for hα3β4 (30, 100 and 1000 µM) and α9α10 (100 and 300 µM). Whole-cell currents were activated by the ACh concentrations indicated. (C) Bar graph of 10 µM sSLURP-1 inhibition of ACh-evoked peak current amplitude mediated by rα9α10 nAChR. ACh concentrations tested were from 10 to 100 µM (ACh EC₅₀ for rα9α10 receptor was 20 μM). Mean ± SEM, n = 6–14. *P < 0.05, **P < 0.0001 vs relative current amplitude in the absence of sSLURP-1, unpaired two-tailed Student’s t-test. (D) Concentration- response curve of sSLURP-1 inhibition of 300 µM ACh-evoked current amplitude mediated by hα3β4 nAChRs. Mean ± SEM, n = 3–10.