GABA(B) localization in hippocampus?

[Matt Jones]

In article <52hq0c$o02 at gap.cco.caltech.edu> Hannah Dvorak,
hdvorak at cns.caltech.edu writes:
>Does anyone know if the distribution of GABA(B) receptors in the 
>hippocampus has been determined?  A reasonably comprehensive 
>literature search turned up studies of localization of GABA(B)
>receptors in cerebellum, vestibular nucleus, central auditory 
>system of the brown bat, and rat GI tract, but nothing from the
>hippocampus.

Hi Hannah,

I'm interested to know what kinds of techniques were used in those
localization studies. The GABA-B receptor hasn't been purified or cloned
yet, and I wasn't aware of any antibodies against it. I'm also guessing
it is hard to do autoradiographic binding because it has a pretty low
affinity as G-protein coupled receptors go. So that leaves
electrophysiological techniques mainly, right?