[Characteristics of sensory neurotransmission in co-culture of neurons from the dorsal root ganglion and dorsal horn spinal cord in rats].

We examined properties of chemical neurotransmission at the level of primary afferent inputs into spinal cord with the new easy-to-use in vitro model of contiguously-cultivated dissociated both the dorsal root ganglion neurons (DRG) and the dorsal horn spinal cord neurons (DHSC) from newborn rats. The results of our studies showed the presence of excitatory and inhibitory DRG neurons synapses on the cells of DHSC. The excitatory afferent signaling in such synapses was mediated by presynaptic release of glutamate and a following activation of both NMDA- and non-NMDA-receptor subclasses. In these cases the activation of non-NMDA-receptors makes a main contribution to realization of excitatory postsynaptic effects. Either glycine- or GABA-ergic DRG neurons were involved in transmission of inhibitory signals to the DHSC neurons. However, in vast majority of examined neuronal pairs the inhibitory synaptic transmission was mediated by presynaptic release of glycine. As distinct from the previous similar methods, an in vitro model of co-culture of both the DRG and the DHSC neurons proposed here allows to use comprehensively modem technical approaches for examination of the transmission of somatosensory information from the periphery to the CNS. The described model could be acceptable for detailed investigation of specific properties of primary afferent synapses.