Muscarinic M1, M3, Nicotinic,GABAA and GABAB Receptor ...

al., 2004). GAD expression, a marker of GABAergic activity showed decreased
expression in corpus striatum. GABA receptors decreased in hypoglycemic rats.
Decreased GABA-mediated inhibition in the corpus striatum is attributed to
changes in biosynthetic capacity of the GAD present (Raza et al., 1994). GABAAα1
and GABAB receptor subtype expression showed down regulation in
hypoglycemic rats compared to diabetic and control rats. Results were confirmed
by immunohistochemical study. All classes of striatal neurons receive prominent
inhibitory GABAergic inputs. These inhibitory interactions are likely to be
essential for striatal processing (Waldvogel et al., 2004). Hypoglycemia induced
decrease in GABAergic function thus impairs striatal inhibitory function. It is
suggested that GABAergic inhibition in the striatum is one of the mechanisms that
normally prevent excessive movements (Nakamura et al., 1990; Yoshida et al.,
1991). Reduced inhibition in the striatum contributes to movement disorders such
as some forms of dystonia (Kreil & Richter, 2005) or myoclonus (Darbin et al.,
2000).
GABAergic inputs to striatal interneurons also originate from several
sources and GABA receptor blockade at these sites, counteracting an ambient
GABAergic tone that contributed to the changes in neuronal spiking. Cholinergic
interneurons receive GABAergic input predominately from Medium Spiny
Neurons collaterals (Martone et al., 1992). GABAergic inhibition in the striatum
also act to inhibit seizure generation (Dematteis et al., 2003) or propagation
(Sasaki et al., 2000; Benedek et al., 2004; Biraben et al., 2004; Bouilleret et al.,
2005;). Short-term and long-term regulation of corticostriatal synaptic efficacy is
critical in some pathophysiological conditions and an altered corticostriatal
synaptic activity has been implicated in neurodegenerative diseases (Calabresi et
al., 1998). Modulations of striatal GABA levels therefore represent a
pharmacological target of interest in the treatment of movement disorders and
seizures. Our results showed decreased GABA receptors in the striatum of the
hypoglycemic rats. This decreased GABA receptors facilitate the rapid spread of
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