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

transcription and cell metabolism (Lipton, 1999), as well as immediate effects on
electrophysiological properties (Krnjevic, 2008) serve to protect neurons, thereby
allowing them to recover from ischemic insults of short duration. It has been
demonstrated that neuronal activity in many systems is required to provide trophic
factors essential for neuronal survival (Thoenen, 1995). Any sustained decrease in
neuronal activity resulting from stress could therefore lead to a decreased supply
of essential trophic factors, which would likely be detrimental to hippocampal
neurons (Johnson & Deckwerth, 1993). Recent investigations have shown that the
hypoglycemic condition, even in the absence of isoelectricity, induce discrete
neuronal damage in vulnerable regions, such as hippocampus, when it is sustained
for prolonged periods of time (Tkacs et al., 2005; Ennis et al., 2008; Haces et al.,
2010). Furthermore, increased lipoperoxidation has been observed in the
hippocampus of hypoglycemic animals not subjected to a coma period (Patockova
et al., 2003; Haces et al., 2010). The impairment in cognitive abilities is associated
with insulin induced hypoglycemic neuronal damage (Roghani et al., 2006).
Present study suggests that cognitive and memory deficits associated with
hypoglycemia is attributed to the altered cholinergic expression and thereby
function mediated through muscarinic receptors in the hippocampus. Stress
condition due to hypoglycemia result in deficits in several neurotransmitter
systems, including cholinergic transmission (Ghajar et al., 1985) which support
the present findings that stress during glucose deprivations affects acetylcholine
metabolism and cholinergic neurotransmission in the hippocampus.
MUSCARINIC RECEPTOR ALTERATIONS IN THE PANCREAS
Diabetes mellitus, characterized by uncontrolled hyperglycemia and
maintenance of blood glucose within the physiological range is critical for the
prevention of diabetes-related complications. Insulin secretion from pancreatic
islet β-cells is a tightly regulated process, under the close control of blood glucose
concentrations and several hormones and neurotransmitters. However, tight
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