title: Synaptic arrangements formed by serotonin-immunoreactive axons in the substantia gelatinosa of the rat spinal cord.
abstract: Ultrastructural properties of serotonin-immunoreactive axons in the rat's substantia gelatinosa were examined in order to determine the synaptic arrangements that they form in the neuropil. Some immunoreactive varicosities formed synaptic associations with somata or dendrites suggesting that serotoninergic systems are capable of influencing the activity of these structures post-synaptically. No examples of axo-axonic synapses were found. Most varicosities, however, did not form identifiable synaptic junctions, but were closely associated with somata, dendrites or axons. Some of these associations may be functional but morphological evidence for this is lacking.
mesh_terms: D000818:Animals; D007395:Interneurons / Q000502:physiology / Q000648:ultrastructure; D008854:Microscopy, Electron; D051381:Rats; D012701:Serotonin / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology*; D013376:Substantia Gelatinosa / Q000166:cytology* / Q000502:physiology / Q000648:ultrastructure; D013569:Synapses / Q000502:physiology / Q000648:ultrastructure
chemical_list: D012701:Serotonin