GABA transporter-1 (GAT-1) immunoreactivity in the cat periaqueductal gray matter.
Using light- and electron-microscopic immunocytochemistry, we investigated the regional distribution and the ultrastructural localization of GAT-1, a prominent GABA transporter, in the cat PAG. Light microscopic observations indicate that GAT-1-immunoreactive elements are particularly dense in PAG-DL and form a pair of longitudinal columns extending in the intermediate region of this structure. At electron-microscopic level, GAT-1 immunoreactivity was present in axon terminals forming symmetric synapses and in the distal processes of astroglial cells. These data further confirm the existence of longitudinal columns within PAG. They also indicate that GAT-1 could influence the action of GABA on its receptors, probably regulating the magnitude and duration of GABA's synaptic action on PAG neurons, and suggest that astrocytes may play an important role in this process.
Institute of Human Physiology, University of Ancona, Italy. fisiolum@popcsi.unian.it
P
P
Barbaresi
G
G
Gazzanelli
M
M
Malatesta
D000818:Animals; D002352:Carrier Proteins / Q000032:analysis*; D002415:Cats; D050485:GABA Plasma Membrane Transport Proteins; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000032:analysis*; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins / Q000032:analysis*; D027361:Organic Anion Transporters; D010487:Periaqueductal Gray / Q000737:chemistry* / Q000648:ultrastructure; D017729:Presynaptic Terminals / Q000737:chemistry / Q000648:ultrastructure; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D002352:Carrier Proteins; D050485:GABA Plasma Membrane Transport Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D027361:Organic Anion Transporters; D005680:gamma-Aminobutyric Acid