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Rp-cAMP

It is well know that /3-adrenoceptors couple to adenylate cyclases to activate a protein kinase A (PKA), but no direct evidence exists for the involvement of the /3-adrenoceptor-PKA signaling pathway in the affective component of pain. Thus, we examined the effect of intra-vBNST administration of a selective PKA inhibitor on isoproterenol- and pain-induced aversion. CPA induced by the intra-vBNST injection of isoproterenol was reversed by the coinjection of Rp-cyclic adenosine monophosphorothioate (Rp-cAMPS), a selective PKA inhibitor. Furthermore, intra-vBNST injection of Rp-cAMPS dose-dependently attenuated the F-CPA. These data suggest that PKA activation within the vBNST via the enhancement of /3-adrenergic transmission is important for the negative affective component of pain (Fig. 3). [Pg.140]

B) This effect is a mediated by a reduction in the sAHP, which curtails repetitive firing in these cells. The serotonin-induced reduction in the sAHP is mediated by 5-HT4 receptors (see text). The 5-HT4 receptor-mediated reduction of /sAHP is suppressed by the selective PKA inhibitor (Rp)cAMPs. [Pg.484]

The necessity of PKA activation for successful preconditioning is demonstrated by the following (i) the beta-adrenergic receptor blocker alprenolol partially abolished ischemic preconditioning (Lochner et al. 1999) (ii) landiolol, a short-acting beta-blocker, blunted the infarct size limitation induced by ischemic preconditioning (Sanada et al. 2004) (iii) PKA inhibitors such as H89 (Sanada et al. 2004 Inserte et al. 2004) and Rp-cAMPs (Sanada et al. 2004) blunted ischemic and dibutyryl-cAMP-induced preconditioning. [Pg.73]

The presence of an interaction between PKC and PKA in modulating TTX-R currents was demonstrated by the finding that the PKC inhibitors, PKCi9 3g staurosporine, significantly attenuated the ability of forskolin to modulate TTX-R currents. In contrast, the PKA inhibitors WIPTIDE and Rp-cAMPs failed to affect the PDBu-mediated changes in increases in peak TTX-R current conductance, although the PDBu effects on kinetics were reduced (Gold et al 1998). [Pg.148]

Fig. 3. Effect of oxytocin (0,1,10 or 100 ng/mL medium) (O) and oxytocin (0,1,10 or 100 ng/mL medium) in combination with protein kinase A inhibitor Rp-cAMPS ( 1 imo ) on prostaglandin (PG)E release by isolated and cultured porcine ovarian follicles. Values are means + SEM. Significant differences (P< 0.05) between cells cultured with and without exogenous oxytocin. Methods of isolation and culture of ovarian follicles, as well as the prostaglandin E radioimmunoassay are described in (8). [Pg.152]

Other protein kinases may indirectly influence the activation of NF-kappap. For example, in contrast to the pro-inflammatory effects typically observed with activation of kinases, the elevation ofcAMP activates PKA and blocks transcription of iNOS mRNA [51,178, 229, 230]. Astrocytes contain a variety of NT receptors that are coupled to Gs-adenylate cyclase [231] and, either activation of P-adrenergic/dopamine receptors or employing agents that increase cAMP, such as forskolin (adenylate cyclase activator), PDE inhibitors [i.e. pentoxifylline], dibutyrl cAMP, or 8-bromo cAMP can attenuate lipopolysaccharide (LPS)/cytokine activated iNOS mRNA in microglia, astrocytes and a number of other cell types [51,176,177,178, 232-237]. In contrast, agents that suppress the intracellular concentration of cAM P such as H-89 and Rp-cAM P are pro-... [Pg.356]

Lu Q, Hutchins AE, Doyle CM, Lundblad JR, Kwok RP (2003) Acetylation of CAMP-responsive element-binding protein (CREB) by CREB-binding protein enhances (REB-dependent Transcription. J Biol Chem. 278(18) 15727-15734... [Pg.210]

In its inactive state, PKA is a tetrameric holoenzyme consisting of two regulatory (R, with four isoforms in humans Rp, R , Rp) and two catalytic (C, with several isoforms in humans) subunits. The binding of four molecules of cAMP to the dimeric R subunit leads to the dissociation of the holoenzyme releasing the active C subunits (Taylor et al., 2004). [Pg.161]

HeUendall RP, Ting JP. 1997. Differential regulation of cytokine-induced major histocompatibility complex class II expression and nitric oxide release in rat microglia and astrocytes by effectors of tyrosine kinase, protein kinase C, and cAMP. J Neuroimmunol 74 19-29. [Pg.83]

Functional evidence also suggests that the adenylyl cyclase second messenger cascade in the cerebellum may be involved in cannabinoid withdrawal. An intrac-erebellar infusion of the cAMP blocker Rp-8Br-cAMPs reduced several behavioral... [Pg.704]

The preparation of (Rp) and (Sp)-N, N, O -tribenzoyladenosine 3, 5 -phosphoranilidates (96) has been greatly improved by treating the cyclic phosphate (97) with oxalyl chloride and a catalytic amount of DMF, rather than the triphenylphosphine-carbon tetrachloride mixture (Appel reaction) used previously, followed by addition of aniline. 5 near-quantitative yield of (97) obtained as a mixture of diastereoisomers is easily separated. The cyclic phosphoramidates (98-100) have also been obtained in improved yield by treating cAMP with a mixture of phosphoryl chloride and trimethyl phosphate (which had previously been pretreated with one-half a molar equivalent of water) at 0°, followed by ammonium carbonate or the appropriate amine. x e (Sp)-diastereoisomers are formed in excess, e.g. for (100) yields of 13 % of the Rp-isomer and 54 % of the Sp-isomer are obtained, and the proportion of Rp-product decreases further if pre-treatment with... [Pg.226]

In these equations, as before, a, j8 and y denote the normalized concentrations of ATP, intracellular cAMP and extracellular cAMP, whereas Py represents the total fraction of receptor in the active state (i.e. the sum of the concentration of the free form R and those of the complexes RP, E, and ES, divided by Rj). [Pg.201]

In the limit of fast binding of extracellular cAMP to both forms of the receptor and fast association between RP and C, C and S, E and S, the following inequality on the rate constants for the reaction steps 1 holds ... [Pg.235]

Employing the p-diastereomer of ATP(aS) as substrate, Coderre and Gerlt (1980) determined the absolute stereochemistry of the product cAMP(S) to be Rp. This result demonstrates that the enzyme catalyses cyclization with overall inversion of stereochemistry at phosphorus. Confirmation was provided by chiral phosphate analysis, taking advantage of the reversibility of the adenylate-cyclase reaction and employing chiral, dia-stereomerically pure cAMP(a 0) as substrate. The most simple explanation for the observed stereochemistry is a mechanism involving direct intramole-... [Pg.221]

As part of their extensive survey of the behaviour of cAMP-dependent systems with analogues of cAMP, Jastorff and his group have compared the substrate specificity of cAMP phosphodiesterase from Dictyostelium discoi-deum with that from beef heart (Van Haastert et ai, 1983). The former is a cell-surface enzyme with low specificity for cAMP, the latter a low- T, (high-affinity) calmodulin-dependent phosphodiesterase. Twenty-five analogues were studied, but our interest lies with the phosphorothioate diastereomers of cAMP(S). The Sp diastereomer is shown to be hydrolysed faster by at least two orders of magnitude than the Rp diastereomer by the beef-heart enzyme, despite similar relative values. The mechanistic interpretation of this phenomenon is based on the theoretical calculations of Van Ool and Buck, and led Jastorff to support Eckstein s double-displacement mechanism, involving pseudorotation (Scheme 37d cf. 37b). [Pg.225]

Since the relative apicophilicity of a hydroxy ligand is greater than that of a sulphydryl, TBPs with apical oxygen will be favoured over those with apical sulphur. Thus with c Jo-adjacent nucleophilic attack, nucleophilic substitution on the S p isomer of cAMP(S) will be favoured over attack on the Rp isomer. This provides one explanation for the selectivity of beef-heart cAMP phosphodiesterase for the Sp isomer of cAMP(S). Analysis based... [Pg.225]

KG Marinova, TD Gurkov, OD Velev, IB Ivanov, B Camp-hell RP Borwankar. Colloids Surfaces A 123/124 155— 167,1997. [Pg.658]

Ld Rg and Rp wtgreeeak the rado of donor to acceptor humpies for eadi species. At aay given cAMP concentration, die observed rado R is... [Pg.670]

Kelly HW, Van Natta ML, Covar RA, Tonascia J, Green RP, Strunk RC. CAMP Research Group. Effect of long-term corticosteroid use on bone mineral density in children a prospective longitudinal assessment in the Childhood Asthma Management Program (CAMP) Study. Pediatrics 2008 122(1) e53-61. [Pg.371]

Reaction of a nucleoside with thiophosphoryl chloride, followed by base-promoted cyclization, provides a direct synthesis of nucleoside-3, 5 -cycllc phosphorothioates (both epimers at phosphorus). 125 Treatment of cyclic AMP with dlphenylphosphoiyl chloride produces the mixed anhydride, predominantly of Rp configuration (62), due to the greater basicity of the axial oxygen in the cAMP. The anhydride reacted with dimethylamine with inversion to give the cyclic phosphoramidate.i26 Activation of cAMP with POCI3 in (MeOlaPO, followed by treatment with an amine, also gave predominantly the Sp-phosphoramidate (63),127 and in the case of a protected cAMP, oxalyl chloride activation achieved a similar result. 128 The hydrolysis of... [Pg.217]

The monodentate ligand (R)-CAMP was soon after replaced by the bidentate bisphosphine ligand (Rp,Rp)-DIPAMP that increased enantioselectivity to 95% ee (Scheme 29.2). " " Application of asymmetric hydrogenation for the industrial synthesis of l-DOPA represents one of the rare examples of very fast transfer of basic knowledge into commercial application. [Pg.867]


See other pages where Rp-cAMP is mentioned: [Pg.238]    [Pg.97]    [Pg.99]    [Pg.471]    [Pg.153]    [Pg.98]    [Pg.73]    [Pg.867]    [Pg.238]    [Pg.97]    [Pg.99]    [Pg.471]    [Pg.153]    [Pg.98]    [Pg.73]    [Pg.867]    [Pg.61]    [Pg.94]    [Pg.349]    [Pg.101]    [Pg.38]    [Pg.38]    [Pg.333]    [Pg.259]    [Pg.226]    [Pg.314]    [Pg.316]    [Pg.198]    [Pg.219]    [Pg.2908]    [Pg.3906]    [Pg.115]   


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CAMP

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