Figure 7

PNU-282987, a selective α7-nAChR agonist, increases the frequency and amplitude of mIPSCs in control rat RGCs. (A) Voltage clamp recording (at −70 mV) of a representative normalized RGC shows that PNU-282987 increases the frequency and amplitude of GABAergic mIPSCs in RGCs. Vertical bar, 200 pA; horizontal bar, 2 min. (B) The recording of the RGC on an expanded scale in time, vertical calibration bar, 50 pA; horizontal calibration bar, 0.5 s. (C,F) Cumulative inter-event interval and amplitude distributions of the mIPSCs of a representative RGC before and during PNU-282987 application. PNU-282987 causes a leftward shift in the inter-event interval (C) and a rightward shift in the amplitude (F) distribution curves, indicating that PNU-282987 significantly increases mIPSC frequency and amplitude (n = 9). ***p < 0.001 (Kolmogorov–Smirnov test). (D,G) Quantification of the frequency (D) and amplitude (G) of the mIPSCs (n = 5). (E,H) Pre-incubation with MLA (1 μM), a selective α7-nAChR antagonist, inhibits the effects of PNU-282987 (10 μM) on the frequency (E) and amplitude (H) of mIPSCs (n = 3). Administration of MLA alone does not affect the baseline frequency (E) or amplitude (H) of the mIPSCs. *p < 0.05, **p < 0.01 (Student’s paired t test). The results in D,E,G, and H are expressed as the mean ± SE.