Rod signals reach ganglion cells via at least five pathways. A new study in this issue of Neuron shows that all pathways from rods to ON-type ganglion cells require connexin36. This is the first physiological demonstration in mammals that a well-defined neural circuit requires a gap junction as an obligatory transmission step.
Demb, J. B., & Pugh, E. N. (2002, November 14). Connexin36 forms synapses essential for night vision. Neuron. Cell Press. https://doi.org/10.1016/S0896-6273(02)01062-0