Figure 2:

Otolith afferent to VS neuron transmission is mediated by mixed electrical and chemical synapses

A. Schematic of whole-cell recording configuration from VS neuron while electrically stimulating otolith afferents.

B. Example EPSCs evoked by electrical stimulation of the otolith afferents; 105 EPSCs overlaid. Arrow indicates onset of stimulation. Stimulus artifact is blanked.

C. Carbenoxolone (CBX) diminishes the fast component of evoked EPSCs while slower component remains. Average traces from an example VS neuron; pre-CBX, n=100; post-CBX, n=100.

D. NBQX abolishes the second, slower component of evoked EPSCs without diminishing the early component. Pre-NBQX, n=349; post-NBQX, n=333.

E. Group data quantifying the reduction of early EPSC amplitude by CBX, n=10.

F. Group data quantifying the total charge transfer that is abolished by NBQX application, n=7.

G. Example EM image of gap junction between identified otolith afferent (pseudocolored purple) and VS neuron (peach), recognizable by the tight apposition of membranes to the exclusion of extracellular space,. Scale bar: 200 nm.

H. Example EM image of chemical synapse between otolith afferent (purple) and VS neuron (peach), characterized by the presence of synaptic vesicles, postsynaptic density, and parallel membranes at the cleft. Scale bar: 200 nm.