Relationships between hair-follicle afferent axons and glycine-immunoreactive profiles in cat spinal dorsal horn.

In order to identify synapses between hair-follicle afferent axons and glycine-containing structures in cat spinal cord, semithin sections containing physiologically identified primary afferent boutons which had been filled with horseradish peroxidase (HRP) were reacted with anti-glycine antiserum, while adjacent ultrathin sections were examined for synaptic contacts. Four axodendritic synapses between hair-follicle afferent boutons and glycine-immunoreactive dendrites and 4 axoaxonic synapses in which HRP-filled boutons were postsynaptic to immunoreactive axons were identified. These results suggest that glycine is involved in the spinal processing of input from A beta hair-follicle afferent axons.