Purinergic synapses formed between rat sensory neurons in primary culture.

ABSTRACT

Though there is some evidence to the contrary, dogma claims that primary sensory neurons in the dorsal root ganglion do not interact, that the ganglion serves as a through-station in which no signal processing occurs. Here we use patch clamp and immunocytochemistry to show that sensory neurons in primary culture can form chemical synapses on each other. The resulting neurotransmitter release is calcium dependent and uses synaptotagmin-containing vesicles. On many cells studied, the postsynaptic receptor for the neurotransmitter is a P2X receptor, an ion channel activated by extracellular ATP. This shows that sensory neurons have the machinery to form purinergic synapses on each other and that they do so when placed in short-term tissue culture.