Long-term potentiation in hippocampus involves sequential activation of soluble guanylate cyclase, cGMP-dependent protein kinase and cGMP-degrading phosphodiesterase, alterations in hyperammonemia
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چکیده
Hyperammonemia is considered the main responsible for the neurological alterations found in liver disease and hepatic encephalopathy, including decreased intelectual and cognitive function. Ammonia affects both excitatory and inhibitory synaptic transmission in the mammalian brain by a variety of mechanisms. LTP is impaired in hyperammonemia and this may contribute to the impairment of cognitive function. However the mechanism by which hyperammonemia impairs LTP remains unclear. We have demnostrated that a sequential activation of soluble guanylate cyclase (sGC), cGMP-dependent protein kinase (PKG) and cGMP-degrading phosphodiesterase (PDE) is necessary for proper induction of LTP.
منابع مشابه
Long-term potentiation in hippocampus involves sequential activation of soluble guanylate cyclase, cGMP-dependent protein kinase, and cGMP-degrading phosphodiesterase.
Previous studies indicate that cGMP is involved in long-term potentiation (LTP). However, the effects of application of tetanus to induce LTP on cGMP content and the mechanisms by which cGMP may modulate LTP have not been reported. The aim of this work was to study the time course of the changes in cGMP content and of the activity of soluble guanylate cyclase (sGC) (the enzyme that synthesizes ...
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