Quantification without purification of blood and tissue adenosine by radioimmunoassay

Bredehorst, Reinhard; Wielckens, Klaus; Kupper, Ernst-Wolfram; Schnabel, Werner Wilhelm; Hilz, Helmuth

doi:10.1016/0003-2697(83)90745-5

Cited by 17 publications

(3 citation statements)

References 26 publications

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“…Adenosine was determined by radioimmunoassay. 13 For the quantitation of NO release, isolated hearts were perfused with constant flow (10.23±0.44 mlxmin-1, n=10) with medium containing 5 ,uM HbO2. NO concentration in the effluent perfusate was continuously measured by a specific difference spectrophotometric assay based on the rapid NOinduced oxidation of HbO2 to methemoglobin.14 Because HbO2 traps the entire amount of NO released in less than 100 msec,9 the measurement of the extinction difference between the absorption maximum and isobestic point of HbO2 versus methemoglobin (a,, 401 nm; a2, 411 nm) in a flow-through cell with a double wavelength spectrophotometer (Hitachi 557, Perkin-Elmer, FRG) permitted the continuous assay of released NO.…”

Section: Methodsmentioning

confidence: 99%

Role of nitric oxide in reactive hyperemia of the guinea pig heart.

Kostić

Schrader

1992

Circulation Research

148

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To evaluate the role of nitric oxide (NO) in the flow response after brief coronary arterial occlusion, NO formation by the isolated guinea pig heart was assessed by a specific difference spectrophotometric assay. Release of NO under basal conditions was 121.8 +/- 10.5 pmol x min-1 and increased to 211.1 +/- 16.8 pmol x min-1 after 60 seconds of coronary occlusion. Simultaneously, release of cGMP and adenosine increased by 87% and 652%, respectively. The kinetics of NO release paralleled the reactive hyperemic flow response. Inhibition of NO synthesis with nitro-L-arginine methyl ester (L-NAME, 30 microM) significantly reduced basal flow and attenuated reactive hyperemia, flow repayment, and repayment ratio. L-NAME decreased release of cGMP but significantly increased adenosine release under basal conditions and during reactive hyperemia. Oxyhemoglobin (5 microM) potentiated the effects of L-NAME. The stereoisomer nitro-D-arginine methyl ester was ineffective. Our results suggest 1) NO is an important regulator of coronary flow during reactive hyperemia as well as under basal flow conditions and 2) the significance of the increased adenosine release when NO synthesis is inhibited remains to be determined.

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Section: Methodsmentioning

confidence: 99%

Role of nitric oxide in reactive hyperemia of the guinea pig heart.

Kostić

Schrader

1992

Circulation Research

148

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“…Under many circumstances, adenosine has been used as a marker for quality control of cultured Cordyceps mycelia [6]. Several methods, including high-performance liquid chromatography (HPLC) [12], fluorescence detection [13,14], and radioimmunoassay [15,16] have been developed to quantify adenosine. In addition, HPLC and thin-layer chromatography (TLC) methods have been reported to quantify the level of adenosine in Cordyceps [17,18].…”

Section: Introductionmentioning

confidence: 99%

Determination of nucleosides in naturalCordyceps sinensis and culturedCordyceps mycelia by capillary electrophoresis

Dong

et al. 2001

Electrophoresis

109

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Cordyceps sinensis is a well-known traditional Chinese medicine, and some of the active components are nucleosides. The analysis of nucleosides in Cordyceps material has been performed by reversed-phase high-performance liquid chromatography (HPLC) with gradient elution or by spectrometry. Here, we have explored the possibility of using capillary electrophoresis to determine the content of three major nucleosides (adenosine, guanosine and uridine) in Cordyceps. Capillary electrophoresis needs no gradients, and it provides a better separation due to its higher efficiency. In order to optimize the resolution, the separation of adenosine, guanosine and uridine was determined in Cordyceps with respect to the variation of buffer concentration, pH, temperature, and voltage. By using the calibrated electrophoresis system, the separation was achieved for the three nucleosides in less than 10 min with a background electrolyte consisting of 0.2 M boric acid-sodium hydroxide buffer, pH 8.5. The nucleoside contents of various types of natural Cordyceps and cultured Cordyceps mycelia were determined and compared. There was a great variation of nucleoside content in different sources of Cordyceps; the cultured Cordyceps mycelia, however, contains a much higher concentration than the natural Cordyceps.

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“…Previous studies on the preparation of adenosine antibodies utilized an A/6-(carboxymethyl) functionality to bind the nucleoside to protein amino groups (13). Thus, a synthetic route to Ñ6-(carboxymethyl)-/V-3-methyladenine (III) was devised and is summarised in Scheme I.…”

Section: Resultsmentioning

confidence: 99%

Isolation of urinary 3-methyladenine using immunoaffinity columns prior to determination by low-resolution gas chromatography-mass spectrometry

Friesen¹,

Garren²,

Prévost³

et al. 1991

Chem. Res. Toxicol.

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An ammonium sulfate precipitated immunoglobin G (IgG) fraction from rabbit antiserum, prepared by use of novel haptenic derivatives, was used to make immunoaffinity columns for purification of 3-methyladenine (3-MeAde) from human urine. IgG was covalently bound to protein A-Sepharose, and the resulting affinity gel columns were sufficiently stable for multiple reuse. 3-MeAde (up to 200 ng) was adsorbed at pH 7.4 and, after extensive washing, eluted with 1 M acetic acid. Recovery of 3-MeAde was typically greater than 90%. For gas chromatography-mass spectrometry analysis, deuterium-labeled (d3) 3-MeAde (50 ng per sample) was used as an internal standard. 3-MeAde was determined as the mono-tert-butyldimethylsilyl derivative and quantitated by measurement of ions at m/z 206 (3-MeAde-d0) and m/z 209 (3-MeAde-d3). Repeated analyses of a human urine sample show excellent reproducibility of the method.

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Quantification without purification of blood and tissue adenosine by radioimmunoassay

Cited by 17 publications

References 26 publications

Role of nitric oxide in reactive hyperemia of the guinea pig heart.

Role of nitric oxide in reactive hyperemia of the guinea pig heart.

Determination of nucleosides in naturalCordyceps sinensis and culturedCordyceps mycelia by capillary electrophoresis

Isolation of urinary 3-methyladenine using immunoaffinity columns prior to determination by low-resolution gas chromatography-mass spectrometry

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