Co-release and interaction of two inhibitory co-transmitters in rat sacral dorsal commissural neurons.

Conventional whole-cell recording configuration was used to characterize the interaction between two inhibitory neurotransmitters, GABA and glycine, in synaptic bouton preparation obtained from rat sacral dorsal commissural nucleus (SDCN). The co-release of GABA and glycine as well as the interaction between their corresponding receptors was demonstrated. Furthermore, taking advantage of pure glycinergic terminal preparation, the possible interaction between GABA and glycine at synaptic level was studied. The results revealed a novel cross-modulation between the two inhibitory cotransmitters systems. This interaction may contribute to sensory processing such as nociception in the mammalian deep dorsal horn under physiological and/or pathological conditions.