A modification of a protein-binding method for rapid quantification of cAMP in cell-culture supernatants and body fluid

Nordstedt, Christer; Fredholm, Bertil B.

doi:10.1016/0003-2697(90)90113-n

Cited by 238 publications

(220 citation statements)

References 8 publications

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“…Plates were chilled for 1 h at 41C and spun at 1000 g for 15 min. cAMP was quantified using a competitive binding assay adapted with minor modifications (Nordstedt and Fredholm, 1990). For measurement of cAMP content, trichloroacetic acid extracts (40 ml) were added to reaction tubes containing cAMP assay buffer (100 mM Tris-HCl, pH 7.4, 100 mM NaCl, 5 mM EDTA).…”

Section: Effects Of Aripiprazole On Camp Productionmentioning

confidence: 99%

Aripiprazole, A Novel Atypical Antipsychotic Drug with a Unique and Robust Pharmacology

Shapiro

Renock

Arrington

et al. 2003

Neuropsychopharmacol

845

701

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Atypical antipsychotic drugs have revolutionized the treatment of schizophrenia and related disorders. The current clinically approved atypical antipsychotic drugs are characterized by having relatively low affinities for D 2 -dopamine receptors and relatively high affinities for 5-HT 2A serotonin receptors (5-HT, 5-hydroxytryptamine (serotonin)). Aripiprazole (OPC-14597) is a novel atypical antipsychotic drug that is reported to be a high-affinity D 2 -dopamine receptor partial agonist. We now provide a comprehensive pharmacological profile of aripiprazole at a large number of cloned G protein-coupled receptors, transporters, and ion channels. These data reveal a number of interesting and potentially important molecular targets for which aripiprazole has affinity. Aripiprazole has highest affinity for h5-HT 2B -, hD 2L -, and hD 3 -dopamine receptors, but also has significant affinity

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Section: Effects Of Aripiprazole On Camp Productionmentioning

confidence: 99%

Aripiprazole, A Novel Atypical Antipsychotic Drug with a Unique and Robust Pharmacology

Shapiro

Renock

Arrington

et al. 2003

Neuropsychopharmacol

845

701

View full text Add to dashboard Cite

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“…Intracellular cyclic AMP levels were measured with a competitive protein binding method [24]. CHO cells expressing four subtypes of recombinant ARs were harvested by trypsinization.…”

Section: Cyclic Amp Accumulation Assaymentioning

confidence: 99%

2-Substituted adenosine derivatives: affinity and efficacy at four subtypes of human adenosine receptors

Gao

Mamedova

Chen

et al. 2004

Biochemical Pharmacology

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The affinity and efficacy at four subtypes (A 1 , A 2A , A 2B and A 3 ) of human adenosine receptors (ARs) of a wide range of 2-substituted adenosine derivatives were evaluated using radioligand binding assays and a cyclic AMP functional assay in intact CHO cells stably expressing these receptors. Similar to previous studies of the N 6 -position, several 2-substituents were found to be critical structural determinants for the A 3 AR activation. The following adenosine 2-ethers were moderately potent partial agonists (K i , nM): benzyl (117), 3-chlorobenzyl (72), 2-(3-chlorophenyl)ethyl (41), and 2-(2-naphthyl)ethyl (130). The following adenosine 2-ethers were A 3 AR antagonists: 2,2-diphenylethyl, 2-(2-norbornan)ethyl, R-and S-2-phenylbutyl, and 2-(2-chlorophenyl)ethyl. 2-(S-2-Phenylbutyloxy)a-denosine as an A 3 AR antagonist right-shifted the concentration-response curve for the inhibition by NECA of cyclic AMP accumulation with a K B value of 212 nM, which is similar to its binding affinity (K i = 175 nM). These 2-substituted adenosine derivatives were generally less potent at the A 1 AR in comparison to the A 3 AR, but fully efficacious, with binding K i values over 100 nM. The 2-phenylethyl moiety resulted in higher A 3 AR affinity (K i in nM) when linked to the 2-position of adenosine through an ether group (54), than when linked through an amine (310) or thioether (1960). 2-[2-(lNaphthyl)ethyloxy]adenosine (K i = 3.8 nM) was found to be the most potent and selective (>50-fold) A 2A agonist in this series. Mixed A 2A /A 3 AR agonists have been identified. Interestingly, although most of these compounds were extremely weak at the A 2B AR, 2-[2-(2-naphthyl)ethyloxy]adenosine (EC 50 = 1.4 µM) and 2-[2-(2-thienyl)-ethyloxy]adenosine (EC 50 = 1.8 (M) were found to be relatively potent A 2B agonists, although less potent than NECA (EC 50 = 140 nM).

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“…Intracellular cyclic AMP levels were measured with a competitive protein binding method [18]. CHO cell that expressed the recombinant human A 3 AR were harvested by trypsinization.…”

Section: Cyclic Amp Accumulation Assaymentioning

confidence: 99%

“…Other species included were nucleoside-like analogues, i.e. a rearranged 4′-thionucleoside analogue (16) and those having carbocyclic rings (17)(18)(19)(20)(21)(22). Substitution of the adenine moiety, where present, followed previously determined substitution patterns to obtain high affinity at the human A 3 AR, such as N 6 -methyl and N 6 -iodobenzyl groups, either alone or in combination with the 2-chloro substituent.…”

Section: Structures Of Ribose-modified Nucleoside Analoguesmentioning

confidence: 99%

Structural determinants of efficacy at A3 adenosine receptors: modification of the ribose moiety

Gao

Jeong

Moon

et al. 2004

Biochemical Pharmacology

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We have found previously that structural features of adenosine derivatives, particularly at the N 6 -and 2-positions of adenine, determine the intrinsic efficacy as A 3 adenosine receptor (AR) agonists. Here, we have probed this phenomenon with respect to the ribose moiety using a series of ribose-modified adenosine derivatives, examining binding affinity and activation of the human A 3 AR expressed in CHO cells. Both 2′-and 3′-hydroxyl groups in the ribose moiety contribute to A 3 AR binding and activation, with 2′-OH being more essential. Thus, the 2′-fluoro substitution eliminated both binding and activation, while a 3′-fluoro substitution led to only a partial reduction of potency and efficacy at the A 3 AR. A 5′-uronamide group, known to restore full efficacy in other derivatives, failed to fully overcome the diminished efficacy of 3′-fluoro derivatives. The 4′-thio substitution, which generally enhanced A 3 AR potency and selectivity, resulted in 5′-CH 2 OH analogues (10 and 12) which were partial agonists of the A 3 AR. Interestingly, the shifting of the N 6 -(3-iodobenzyl)adenine moiety from the 1′-to 4′-position had a minor influence on A 3 AR selectivity, but transformed 15 into a potent antagonist (16) (K i = 4.3 nM). Compound 16 antagonized human A 3 AR agonist-induced inhibition of cyclic AMP with a K B value of 3.0 nM. A novel apio analogue (20) of neplanocin A, was a full A 3 AR agonist. The affinities of selected, novel analogues at rat ARs were examined, revealing species differences. In summary, critical structural determinants for human A 3 AR activation have been identified, which should prove useful for further understanding the mechanism of receptor activation and development of more potent and selective full agonists, partial agonists and antagonists for A 3 ARs.

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A modification of a protein-binding method for rapid quantification of cAMP in cell-culture supernatants and body fluid

Cited by 238 publications

References 8 publications

Aripiprazole, A Novel Atypical Antipsychotic Drug with a Unique and Robust Pharmacology

Aripiprazole, A Novel Atypical Antipsychotic Drug with a Unique and Robust Pharmacology

2-Substituted adenosine derivatives: affinity and efficacy at four subtypes of human adenosine receptors

Structural determinants of efficacy at A3 adenosine receptors: modification of the ribose moiety

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