The synaptic architecture of the cone pedicle

The synaptic architecture of the cone pedicle In the human retina exist approximately 120 million rods and 6 million cones. Subsequent to its absorption, the light is transduced by these cells into an electrical signal. This signal is transmitted via glutamate release onto bipolar cells, which then in turn innervate the retinal ganglion cells. The cones are responsible for daylight and colour vision, as well as for visual acuity, and they exhibit a highly complex synaptic architecture. At the cone pedicle - the earliest synapse in the visual system - the light signal is already modulated and split into many parallel pathways. The expression of different neurotransmitter receptors on numerous postsynaptic neurons plays a pivotal role in these mechanisms, not less than the intercellular coupling via electrical synapses. By the use of confocal laser scanning microscopy and electron microscopy we are able to investigate the synaptic components and their distribution - to gain insight into the function of this extraordinary synapse.