Characterization of Vicia villosa agglutinin-labeled GABAergic interneurons in the hippocampal formation and in acutely dissociated hippocampus.
The distribution, morphology, and ionic conductances of Vicia villosa agglutinin (VVA)-labeled cells were examined in the rat hippocampal formation. The heaviest labeling and highest density of labeled neurons were found in the subicular complex. Lighter VVA-labeling and fewer labeled cells were found in hippocampal strata pyramidale, oriens, and alveus. VVA-labeled cells were found to be heterogeneous morphologically, including multipolar, bipolar, and basket-like shapes. The majority of VVA-labeled cells contained GABA and parvalbumin immunoreactivity; thus VVA-labeled cells in the hippocampal formation resemble previously described VVA-labeled neurons in cerebral cortex. Electrophysiological properties of subicular VVA-labeled cells were studied in an acutely dissociated neuron preparation. Dissociated cells were labeled in vitro with VVA coupled either to a fluorescent marker or to small beads. The viability of labeled dissociated cells was confirmed, and identified cells were partially characterized electrophysiologically using whole-cell voltage clamp recording. VVA-labeled cells were electrophysiologically similar to pyramidal cells from the same region, except that the VVA-labeled cells showed only small transient outward currents.
Department of Pharmacology, University of Washington, Seattle 98195.
C T
CT
Drake
K A
KA
Mulligan
T L
TL
Wimpey
A
A
Hendrickson
C
C
Chavkin
D000818:Animals; D002469:Cell Separation / Q000379:methods; D004594:Electrophysiology / Q000379:methods; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D066298:In Vitro Techniques; D007395:Interneurons / Q000166:cytology / Q000502:physiology*; D037102:Lectins; D008297:Male; D008564:Membrane Potentials; D037121:Plant Lectins; D011712:Pyramidal Tracts / Q000166:cytology / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D037102:Lectins; D037121:Plant Lectins; C042242:Vicia lectins; D005680:gamma-Aminobutyric Acid