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Erythrocyte membrane permeability in the men with metastatic adenocarcinoma of the prostate.
Veshapidze, N, Alibegashvili, M, Gabunia, N, Ramishvili, L, Kotrikadze, N
Georgian medical news. 2009;(166):9-12
Abstract
The aim of our study was to investigate the alterations of the erythrocyte membrane permeability in the men with metastatic adenocarcinoma of the prostate before and six months after castration. For experimental research were used the erythrocytes of 15 men with metastatic prostate cancer (Pca) (before and after 6 months from castration) and of the 15 practically healthy men (control group). The patients age was vacillate from 60 to 75 years old. Clinical stage of the disease was established at A. Tsulukidze National Center of Urology. Investigations revealed the changes of Na(+)/K(+)-ATP-ase activity and the changes of Na(+) and K(+) ions concentration in metastatic Pca patients before and six months after castration. It was determined that after the castration alterations of the erythrocytes transportive function is less pronounced in comparison with pre-operational data; These indicate the overall improvement of the organism's condition in the post-operational period and partial recovery of the cellular homeostasis.
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The in vivo and in vitro effects of L-carnitine supplementation on the erythrocyte membrane acetylcholinesterase, Na+, K+-ATPase and Mg2+-ATPase activities in basketball players.
Parthimos, T, Schulpis, KH, Angelogianni, P, Tsopanakis, C, Parthimos, N, Tsakiris, S
Clinical chemistry and laboratory medicine. 2008;(1):137-42
Abstract
BACKGROUND We investigated whether the activities of erythrocyte membrane acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase are modulated in basketball players pre- vs. post-forced training with or without L-carnitine (L-C) supplementation. METHODS Blood was obtained from 10 male players pre-game (group A) and post-game (group B) and after 1 month L-C supplementation (2 g/24 h orally) pre-training (group C) and post-training (group D). Lactate, pyruvate and total antioxidant status (TAS) were measured with commercial kits, catecholamines with HPLC and the enzyme activities spectrophotometrically. RESULTS Lactate, pyruvate, AChE, Na+, K+-ATPase and catecholamines were increased (p<0.001) and TAS was decreased (p<0.001) in group B. In contrast, TAS remained unaltered and the all enzyme activities were reduced (p<0.001) in group D at the same time of study. Mg2+-ATPase activity remained unchanged. In vitro incubation of the modulated AChE and Na+, K+-ATPase with L-C (25 microM) from group B and group D resulted in a non-significant reduction of the enzymes in group B and complete restoration of their activities in group D. CONCLUSIONS The increase of AChE and Na+, K+-ATPase activities may be due to the elevation of catecholamines in group B. Carnitine utilization by the muscles during training may result in a reduction of the enzyme activities (group D). The latter is supported by the recovery of the enzyme activities after incubation of the membranes from group D with L-C.
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3.
Ion fluxes in giant excised cardiac membrane patches detected and quantified with ion-selective microelectrodes.
Kang, TM, Markin, VS, Hilgemann, DW
The Journal of general physiology. 2003;(4):325-47
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Abstract
We have used ion-selective electrodes (ISEs) to quantify ion fluxes across giant membrane patches by measuring and simulating ion gradients on both membrane sides. Experimental conditions are selected with low concentrations of the ions detected on the membrane side being monitored. For detection from the cytoplasmic (bath) side, the patch pipette is oscillated laterally in front of an ISE. For detection on the extracellular (pipette) side, ISEs are fabricated from flexible quartz capillary tubing (tip diameters, 2-3 microns), and an ISE is positioned carefully within the patch pipette with the tip at a controlled distance from the mouth of the patch pipette. Transport activity is then manipulated by solution changes on the cytoplasmic side. Ion fluxes can be quantified by simulating the ion gradients with appropriate diffusion models. For extracellular (intrapatch pipette) recordings, ion diffusion coefficients can be determined from the time courses of concentration changes. The sensitivity and utility of the methods are demonstrated with cardiac membrane patches by measuring (a) potassium fluxes via ion channels, valinomycin, and Na/K pumps; (b) calcium fluxes mediated by Na/Ca exchangers; (c) sodium fluxes mediated by gramicidin and Na/K pumps; and (d) proton fluxes mediated by an unknown electrogenic mechanism. The potassium flux-to-current ratio for the Na/K pump is approximately twice that determined for potassium channels and valinomycin, as expected for a 3Na/2K pump stoichiometery (i.e., 2K/charge moved). For valinomycin-mediated potassium currents and gramicidin-mediated sodium currents, the ion fluxes calculated from diffusion models are typically 10-15% smaller than expected from the membrane currents. As presently implemented, the ISE methods allow reliable detection of calcium and proton fluxes equivalent to monovalent cation currents <1 pA in magnitude, and they allow detection of sodium and potassium fluxes equivalent to <5 pA currents. The capability to monitor ion fluxes, independent of membrane currents, should facilitate studies of both electrogenic and electroneutral ion-coupled transporters in giant patches.
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Hypothalamic digoxin, regulation of neuronal transmission, and cerebral dominance.
Kurup, RK, Kurup, PA
The International journal of neuroscience. 2003;(6):821-30
Abstract
The present study assessed the neurochemical differences between right hemispheric dominant and left hemispheric dominant individuals. The HMG CoA reductase activity, serum digoxin, magnesium, tryptophan catabolites, tyrosine catabolites, and RBC membrane (Na+)-K+ ATPase activity were measured in individuals of differing hemispheric dominance. The results showed that right hemispheric dominant individuals had elevated digoxin synthesis, increased tryptophan catabolites, and reduced tyrosine catabolites and membrane (Na+)-K+ ATPase with hypomagnesemia. Left hemispheric dominant individuals had the opposite patterns. Right hemispheric dominance represents a hyperdigoxinemic state with membrane sodium-potassium ATPase inhibition. Left hemispheric dominance represents the reverse pattern with hypodigoxinemia and membrane sodium-potassium ATPase stimulation.
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Hypothalamic-mediated model for Creutzfeldt-Jakob disease: relation to hemispheric chemical dominance.
Kurup, RK, Kurup, PA
The International journal of neuroscience. 2003;(7):971-87
Abstract
The isoprenoid pathway including endogenous digoxin was assessed in Creutzfeldt-Jakob Disease (CJD). This was also studied for comparison in patients with right hemispheric and left hemispheric dominance. The isoprenoid pathway was upregulated with increased digoxin synthesis in patients with CJD and in those with right hemispheric chemical dominance. In this group of patients (i) the tryptophan catabolites were increased and the tyrosine catabolites reduced, (ii) the dolichol and glycoconjugate levels were elevated, (iii) lysosomal stability was reduced, (iv) ubiquinone levels were low and free radical levels increased, and (v) the membrane cholesterol:phospholipid ratios were increased and membrane glyco conjugates reduced. On the other hand, in patients with left hemispheric chemical dominance, the reverse patterns were obtained. The role of the isoprenoid pathway in the pathogenesis of CJD and its relation to hemispheric chemical dominance is discussed.
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Hypothalamic digoxin, cerebral chemical dominance, and calcium/magnesium metabolism.
Kurup, RK, Kurup, PA
The International journal of neuroscience. 2003;(7):999-1004
Abstract
The study assessed the biochemical differences between right hemispheric dominant and left hemispheric dominant individuals. The HMG CoA reductase activity, isoprenoid metabolites--serum digoxin--serum magnesium, and RBC membrane Na+-K+ ATPase activity were also studied. The results showed that right hemispheric chemically dominant individuals had increased (i) HMG CoA reductase activity, elevated digoxin levels, (ii) reduced RBC membrane Na+-K+ ATPase activity and serum magnesium levels. Left hemispheric chemically dominant individuals had the opposite patterns. Right hemispheric chemical dominance represents a hyperdigoxinemic/hypomagnesemic state with membrane sodium-potassium ATPase inhibition. Left hemispheric chemical dominance represents the reverse pattern with hypodigoxinemia/hypermagnesemia and membrane sodium-potassium ATPase stimulation. Cerebral chemical dominance can regulate calcium/magnesium metabolism.
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The concept of cerebral chemical dominance.
Kurup, RK, Kurup, PA
The International journal of neuroscience. 2003;(7):957-70
Abstract
The study assessed the biochemical differences between right hemispheric dominant and left hemispheric dominant individuals detected by handedness and the dichotic listening test. The isoprenoid metabolites--digoxin, dolichol, and ubiquinone, glycoconjugate metabolism, free radical metabolism, and the RBC membrane composition were studied in individuals with differing hemispheric dominance. The results showed that all right hemispheric dominant individuals and 50% of left hemispheric dominant individuals had increased HMG CoA reductase activity, elevated digoxin and dolichol levels. The serum magnesium, RBC membrane Na+-K+ ATPase activity and serum ubiquinone levels were reduced in all right hemispheric dominant individuals and 50% of left hemispheric dominant individuals. The tryptophan-derived neurotransmitters--serotonin, quinolinic acid, strychnine, and nicotine--were increased while the tyrosine derived neurotransmitters--dopamine, noradrenaline, and morphine--were reduced in all right hemispheric dominant individuals and 50% of left hemispheric dominant individuals. The other 50% of left hemispheric dominant individuals had decreased HMG CoA reductase activity, reduced digoxin, and dolichol levels. The serum magnesium, RBC membrane Na+-K+ ATPase activity, and serum ubiquinone levels were increased in this group. The tryptophan derived neurotransmitters--serotonin, quinolinic acid, strychnine, and nicotine were reduced, while the tyrosine-derived neurotransmitters--dopamine, noradrenaline, and morphine-- were increased in the rest (50% of left hemispheric dominant individuals). Hemispheric dominance detected by the dichotic listening test and handedness has no correlation with cerebral chemical dominance.