Figure 7. CT synapses in assembloids undergo LTD.

(A) Schematic of the experimental condition for CT LTD induction and the 1-Hz LTD-induction protocol.

(B) Bar graph of the average responses of 10 individual cells from 9 assembloids after CT LTD induction in aCSF. Shades of gray indicate different batches of assembloids; vertical lines denote separate assembloids.

(C) Time course data show that 1-Hz stimulation (thick dashed line) induced LTD in CT synapses (black, n = 10 cells/9 assembloids). MPEP (blue, n = 6 cells/6 assembloids), AP5 (green, n = 5 cells/4 assembloids), or iBAPTA (orange, n = 4 cells/4 assembloids) blocked LTD induction. Shaded area depicts the presence of bath-applied drugs. The first (1) and final (2) 5 min of the experiment are noted.

(D) Time course of Rs normalized to the 5-min baseline period, demonstrating that CT LTD is not due to changes in Rs.

(E) Bar graph of group data after 1-Hz stimulation from (C). Differences from baseline were evaluated by one-sample t-test (μ = 100, ###p <0.001). Differences between treatments and aCSF were evaluated by one-way ANOVA, p = 0.0004. Dunnett’s test: ***p <0.001.

(F) Example traces from the first (1) and final (2) 5 min of the experiment across conditions. Circles indicate electrical stimulation.

Scale bars for (A): 5 mV, 100 ms. Scale bars for (F): 50 pA, 200 ms. Data shown are mean ± SEM (C), (D), and (E), with individual data points overlaid in (E).

See Figure S7 for PPR analysis and analysis of organoid/assembloid age and CT LTD expression.