Nitric oxide dependent cyclic guanosine

Synthesized by soluble guanylyl cyclase and particulate guanylyl cyclase from guanosine triphosphate (GTP). Nitric oxide activates soluble guanylyl cyclase to enhance cyclic GMP production that contributes to various NO actions. Cyclic GMP is hydrolyzed by phosphodiesterases. Cyclic GMP binds to and activates cGMP-dependent protein kinase, phosphodiesterases, and Cyclic Nucleotide-regulated Cation Channels. 

Schmidtko, A., Ruth, P., Geisslinger, G., and Tegeder, I. (2003). Inhibition of cyclic guanosine S -monophosphate-dependent protein kinase I (PKG-I) in lumbar spinal cord reduces formalin-induced hyperalgesia and PKG upregulation. Nitric Oxide 8, 89-94. 

The precise mechanisms that explain protamine-mediated systemic hypotension are unknown, but there is evidence that it may be mediated by the endothelium and dependent on nitric oxide/cyclic guanosine monophosphate it has been suggested that methylthioninium chloride (methylene blue) may be of use in treating hemodynamic complications caused by the use of protamine after cardiopulmonary bypass (4). 

Fig. 76.2 Polyphenols and polyphenol-rich sources induce endothelial-dependent NO- and EDH-mediated relaxations. Polyphenols are potent inducers of the oidothelial formation of nitric oxide (NO) and endothelium-derived hyperpolarizatitm (EDH) via a redox-soisitive mechanism. SKca small conductance calcium-activated potassium channels, IKca intermediate conductance calcium-activated potassium channels, Src Src family kinase, PI3K phosphatidylinositol 3-kinase, eNOS endothelial NO synthase, L-Arg L-arginine, sGC soluble guanylyl cyclase, GTP guanosine triphosphate, cGMP cyclic guanosine monophosphate, AA arachidonic acid, COX cyclooxygenase, ATP adenosine triphosphate, cAMP cyclic adenosine monophosphate...

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