Fig. 4

ATop: Example of iGluSnFR signals from an individual OFF synapse elicited using a stimulus of variable contrast in the morning (0–100%, 5 Hz modulation). In this example, note the high levels of spontaneous activity that were quantified as the responses elicited at zero contrast (red dashed box). Bottom. Examples of iGluSnFR signals from the same OFF synapse after intravitreal injection of ADTN. Note the increase in amplitude and frequency of events and the reduction of spontaneous activity. In each case the top trace shows the iGluSnFR signal and the lower trace the estimated Q_e. B Quantification of spontaneous events composed by different Q_e in OFF synapses in the morning, morning + ADTN and afternoon (OFF morning, n = 20 synapses; OFF morning + ADTN n = 12 synapses; OFF afternoon, n = 24 synapses). Note the suppression of spontaneous events in OFF synapses after intravitreal injection of ADTN in the morning. Each point shows the mean ± s.e.m. C Quantification of spontaneous events composed by different Q_e in ON synapses in the Morning, Morning + ADTN and Afternoon (ON Morning n = 12 synapses; ON Morning + ADTN n = 5 synapses; ON Afternoon, n = 17 synapses). Note that spontaneous activity levels were not dramatically altered after administration of ADTN. Each point shows the mean ± s.e.m. Source data are provided as a Source Data file.