title: Putative GABAergic input to axons of spinal interneurons and primary sensory neurons in the lamprey spinal cord as shown by intracellular Lucifer yellow and GABA immunohistochemistry.
abstract: GABAergic phasic modulation of the membrane potential occurs in spinal interneurons during fictive locomotion in lamprey presumably indicating a presynaptic inhibition. GABA also modulates synaptic transmission from primary sensory neurons (dorsal cells) at a presynaptic site. From these findings GABA terminals would be expected to be in close contact with phasically modulated axons of spinal interneurons and/or dorsal cells and their axons. To test this supposition intracellular injections of Lucifer yellow into spinal interneurons or dorsal cells were combined with GABA immunohistochemistry. GABA-immunoreactive (ir) varicosities were found to be in close contact (less than 1 micron distance) with axons modulated during fictive locomotion as well as dorsal cell axons. Small GABA-ir bipolar neurons form processes, which are in close contact with the axons of dorsal cells.
authors.affiliation: Nobelinstitute for Neurophysiology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Christenson
authors.forename: F
authors.initials: F
authors.lastname: Bongianni
authors.forename: S
authors.initials: S
authors.lastname: Grillner
authors.forename: T
authors.initials: T
authors.lastname: Hökfelt
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D007150:Immunohistochemistry; D007395:Interneurons / Q000502:physiology*; D007546:Isoquinolines; D007798:Lampreys / Q000502:physiology*; D009475:Neurons, Afferent / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: D007546:Isoquinolines; D005680:gamma-Aminobutyric Acid; C017475:lucifer yellow