NADH supplementation decreases pinacidil‐primed I_K(ATP) in ventricular cardiomyocytes by increasing intracellular ATP

Abstract

1 The aim of this study was to investigate the effect of nicotinamide-adenine dinucleotide (NADH) supplementation on the metabolic condition of isolated guinea-pig ventricular cardiomyocytes. The pinacidil-primed ATP-dependent potassium current I K(ATP) was used as an indicator of subsarcolemmal ATP concentration and intracellular adenine nucleotide contents were measured. 2 Membrane currents were studied using the patch-clamp technique in the whole-cell recording mode at 36 -371C. Adenine nucleotides were determined by HPLC.

Development of an ion‐pair HPLC method for investigation of energy charge changes in cerebral ischemia of mice and hypoxia of Neuro‐2a cell line

“…Its value should approach unity in a cell with maximum energy status and fall to zero in a fully depleted cell (Atkinson, 1968). Different methods have been used to measure adenine nucleotides, including enzyme assay (Hearse, 1984), bioluminescence, P 31 nuclear magnetic resonance spectroscopy (NMR), high-performance capillary electrophoresis (HPCE), gas chromatography (GC), high-performance liquid chromatography with ultraviolet light detection (HPLC-UV) (Childs et al, 1996;Pelzmann et al, 2003;Jahraus et al, 2001;Peveri et al, 1992), gradient HPLC (Brown, 1970;Harmsen et al, 1982;Webster et al, 1985) and ion-exchange methods (Anderson, 1962). The present study reports the ionpair reversed-phase HPLC method which, without any chemical manipulation of samples except for trichloroacetic acid (TCA) treatment of cells, allows the direct simultaneous separation adenine nucleotides.…”

Simultaneous determination of adenosine triphosphate and its metabolites in human whole blood by RP-HPLC and UV-detection

“…Several methods have been published to measure nucleotides, including an enzyme assay [10], bioluminescence, 31 P nuclear magnetic resonance spectroscopy (NMR), high-performance capillary electrophoresis (HPCE), gas chromatography (GC), ion-pair reversed-phase HPLC [11][12][13][14][15][16], gradient HPLC [17][18][19], and ion-exchange methods [20]. RP-HPLC lacks some of the drawbacks of other methods, like, for ion-exchange HPLC, the need for highly concentrated elution buffers and long analysis times.…”

Development of an HPLC method for determination of metabolic compounds in myocardial tissue

“…Reperfusion of an ischemic heart showed partial or complete recovery of myocardial high-energy phosphate contents, depending upon the period during which the heart had been exposed to ischemia [2]. Different methods were used to measure metabolic compounds: enzymatic [3,4], high-performance liquid chromatography with ultraviolet light detection (HPLC-UV) [5][6][7][8][9][10][11][12][13], gradient HPLC [14][15][16] or ion-exchange methods [17,18] have been performed with this purpose. In the present work, an isocratic HPLC method with ion-pair system and replacing of ion exchange of previous ones, was optimized and validated for the simultaneous determination of these compounds in extracts from frozen clamped myocardial tissue.…”