Guanosine-3,5-cyclic monophosphate

Cyclic nucleotide phosphodiesterases (PDEs) are a class of enzymes that catalyze the hydrolysis of 3, 5 -cyclic guanosine monophosphate (cGMP) or 3, 5 -cyclic adenosine monophosphate (cAMP) to 5 -guanosine monophosphate (GMP) or 5 -adenosine monophosphate (AMP), respectively. 

Cyclic guanosine monophosphate l,3-Diphenyl-6-vinyl-l//-pyrazolo[3,4-i>]quinoline... 

Reagents. Cyclic nucleotides (3, 5 -cyclic adenosine monophosphate (c-AMP), 3, 5 -cyclic guanosine monophosphate (c-GMP), and 3, 5 -cyclic inosine monophosphate (c-IMP)) sodium tetraborate hydrochloric acid and potassium hydroxide were purchased from Sigma Chemical Company, St. Louis, Missouri). Millex disposable filter units (0.22 pm) were obtained from Millipore Corporation (Bedford, Massachusetts). Triply distilled and deionized water was used for the preparation of buffer solutions. Both buffers and samples were routinely degassed with helium after filtration (using microfilter units). 

De Vente, J, Steinbusch, H. W. M., and Schipper, J (1987) A new approach to immunocytochemistry of 3, 5 -cyclic guanosine monophosphate preparation, specificity, and initial application of a new antiserum against formaldehyde-fixed 3, 5 -cychc guanosine monophosphate. Neuroscience 22,361—373. 

Shuttleworth, C. W., Xue, C., Ward, S. M., De Vente, J., and Sanders, K. M. (1993) Immunohistochemical localization of 3, 5 -cyclic guanosine monophosphate in the canine proximal colon, responses to nitnc oxide and electncal stimulation of enteric inhibitory neurons. Neuroscience 56,513-522. 

Fig. 2.14 Dependence of the rate of reaction of 3, 5 -cyclic guanosine monophosphate (cGMP) on the arene in [(r -arene)Ru(en)(H20)] complexes, as determined by integration of the nucleotide H NMR H8 peak for the...

Cyclic Guanosine Monophosphate Guanylyl Cyclase Nitric Oxide Carbon Monoxide... 

Cyclic Nucleotide-regulated Cation Channels Cyclic Guanosine Monophosphate... 

Cyclic Adenosine Monophosphate Table Appendix Membrane Transport Proteins Cyclic Guanosine Monophosphate Non-Selective Cation Channels... 

Adenylyl Cyclases Guanylyl Cyclases Transmembrane Signalling Cyclic Adenosine Monophosphate Cyclic Guanosine Monophosphate Cyclic Nucleotide-gated Channels Phosphodiesterases... 

Cyclic Guanosine Monophosphate Guanylyl Cyclases Smooth Muscle Tone Regulation... 

Cyclic-AMP Response Element Binding Protein Cyclic GMP-dependent Protein Kinase Cyclic GMP-regulated Phosphodiesterases Cyclic Guanosine Monophosphate (Cyclic GMP cGMP)... 

Dipyridamole exerts its effect by inhibition of platelet phosphodiesterase E5, increasing cyclic guanosine monophosphate and cyclic adenosine monophosphate (cAMP). By inhibiting its uptake and metabolism by erythrocytes, dipyridamole also increases the availability of adenosine within blood vessels, promoting inhibition of platelet aggregation and local vasodilatation. " Dipyridamole may also inhibit cAMP phosphodiesterase in platelets, which further increases cAMP levels and may enhance endothelial nitric oxide production, contributing to its antithrombotic effect. Existing trials of dipyridamole in stroke have focused on secondary prevention and will be discussed briefly. 

The effect of receptor stimulation is thus to catalyze a reaction cycle. This leads to considerable amplification of the initial signal. For example, in the process of visual excitation, the photoisomerization of one rhodopsin molecule leads to the activation of approximately 500 to 1000 transdudn (Gt) molecules, each of which in turn catalyzes the hydrolysis of many hundreds of cyclic guanosine monophosphate (cGMP) molecules by phosphodiesterase. Amplification in the adenylate cyclase cascade is less but still substantial each ligand-bound P-adrenoceptor activates approximately 10 to 20 Gs molecules, each of which in turn catalyzes the production of hundreds of cyclic adenosine monophosphate (cAMP) molecules by adenylate cyclase. 

Forte LR, Eber SL, Turner JT, Freeman RH, Fok KF, Currie MG Guanylin stimulation of Cl- secretion in human intestinal T84 cells via cyclic guanosine monophosphate. J Clin Invest 1993 91 2423-2428. 

CGD cGMP ci- CMC CMML chronic granulomatous disease cyclic guanosine monophosphate chloride ion critical micellar concentration chronic myelomonocytic leukaemia... 

Guanylate cyclase converts guanosine triphosphate (GTP) to cyclic guanosine monophosphate (cyclic GMP). 

Fig. 3. Mechanisms of vasocontraction and vasorelaxation in endothelial and smooth muscle cells. COX cyclooxygenase, eNOS endothelial nitric oxide synthase, HO-1 heme oxygenase-1, EET epoxyeicosatrienoic acid, EDHF endothelium-derived hyperpolariz-ing factor, PGI2 prostaglandin I2, NO nitric oxide, CO carbon monoxide, PLC phospholipase C, IP3 inositol 1,4,5-trisphosphate, DAG diacylglycerol, ER/SR endo-plasmic/sarcoplasmic reticulum, AC adenylyl cyclase, cAMP cyclic adenosine monophosphate, sGC soluble guanylyl cyclase, cGMP cyclic guanosine monophosphate.

Fig. 1. The EDRF/NO pathway in vascular smooth muscle. Vasodilatation by nitrates at a cellular level. Nitrates, nitrites, and nitroprusside-Na are able to release nitric oxide (NO), which stimulates the conversion of GTP into cyclic guanosine monophosphate (cGMP), thus causing vasodilatation. The release of EDRF (=NO) from endothelial cells can be stimulated by various endogenous compounds. Endogenous EDRF (=NO) then causes vasodilatation, similar to the NO released by...

NOS-containing neurons have a very discrete localization in the CNS, representing only 1% of neuronal cells. However, their axons ramify so extensively that virtually every cell in the brain may encounter a NOS nerve terminal. As a diatomic gas, NO is freely diffusible and thus can readily enter adjacent neuronal cells. Once inside the target cell, NO binds the iron in heme contained within the active site of soluble guanylyl cyclase, activating the enzyme to form cyclic guanosine monophosphate (GMP). The activity of NO is therefore mediated by an enzyme receptor. In neurons, NO is formed in response to calcium influx reminiscent of calcium-dependent exocytotic release of neurotransmitters. 

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