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PubMed1994

In vitro development of bovine embryos as affected by different lots of bovine serum albumin and citrate.

The effect of bovine serum albumin (BSA) lots on the development of in vitro-derived bovine embryos in synthetic oviductal fluid was investigated. Citrate concentration was determined for each lot of BSA, and then correlated with differences noted in the ability of BSA lots to support embryo development. Development of bovine embryos to the blastocyst stage was also compared after culture in chemically-defined medium with varying levels of citrate. There were distinct differences in the ability of the different BSA lots to support embryo development to the blastocyst stage (P<or=0.05). Citrate content (based on 3.2% BSA) of the medium varied from 320 to 1280 microM. Although there was an overall linear trend (P<0.001) for increased number of blastocysts with increasing concentrations of citrate in the medium, there were also substantial deviations (P=0.024) from this linear trend, suggesting that factors other than citrate could be responsible for stimulating blastocyst development. In the second experiment, the percentages of cleaved embryos that developed to the blastocyst stage in defined medium with 0, 100, 300 or 900 microM citrate ranged from 18.2 to 27.8% and were similar among treatments (P=0.441). The mean number of cells in the embryos developing to the blastocyst stage did not differ among treatments (P=0.545). Overall, these results indicate citrate has little affect on development of bovine embryos to the blastocyst stage in vitro.

Journal Article↗
PubMed1996

Sequence parameters of double spin-echo sequences affect quantification of citrate.

Quantification of citrate by localized 1H spectroscopy is usually performed using the water signal as reference, but the signal behavior of the J-coupled AB spin system of citrate after multipulse excitation is not as trivial as for uncoupled substances. The influence of the timing scheme of double spin-echo sequences and of the spatial flip angle distribution of (nonideal) refocusing pulses was analyzed systematically for the citrate resonances. Both single echo times of the double spin-echo sequence were varied between 20 ms and 250 ms in theoretical and experimental approaches. Relatively long total echo times (TE > 120 ms) provide high selectivity to citrate signals, since signals from triglycerides at 2.6 ppm are markedly reduced. Asymmetrical timing schemes of the double spin-echo sequence with one short single echo time of 20 ms and one longer single echo time of about 120 ms result in high integral signal from the central lines of citrate, whereas symmetrical timing leads to high sensitivity for total echo times TE near 100 ms. The integral citrate signals in spectra with relatively long echo times (TE > 120 ms) were found to depend markedly on the type of the refocusing pulses, affecting quantitative citrate measurements in vitro and in vivo.

Citric Acid↗
PubMed1993

Induction of oxidative single- and double-strand breaks in DNA by ferric citrate.

The relative risk of primary hepatocellular carcinoma in genetic hemochromatosis (GH) is estimated at over 200 times as that of control populations. Recently, ferric ion chelated to citrate (Fe-citrate) was identified as the major non-transferrin-bound iron in the serum of GH patients. We investigated whether low concentration of Fe-citrate plus reductant could damage supercoiled plasmid DNA under physiological pH and ionic strength. Incubation of Fe-citrate with either H2O2, L-ascorbate, or L-cysteine induced single- and double-strand breaks in supercoiled plasmid pZ189 in a concentration- and time-dependent fashion. DNA strand breaks produced by Fe-citrate plus H2O2 increased at reduced pH (< or = 6.9). Catalase and free radical scavengers inhibited the DNA breakage produced by Fe-citrate in combination with each reductant, suggesting that H2O2 and finally .OH are responsible DNA damaging species. The catalytic ability of Fe-citrate to induce DNA strand breaks, particularly double-strand breaks (DSBs), may contribute to the carcinogenic processes observed in GH.

Ascorbic Acid↗
PubMed2006

Functional characterization of Na+ -coupled citrate transporter NaC2/NaCT expressed in primary cultures of neurons from mouse cerebral cortex.

Neurons are known to express a high-affinity Na+ -coupled dicarboxylate transporter(s) for uptake of tricarboxylic acid cycle intermediates, such as alpha-ketoglutarate and malate, which are precursors for neurotransmitters including glutamate and gamma-aminobutyric acid. There is, however, little information available on the molecular identity of the transporters responsible for this uptake process in neurons. In the present study, we investigated the characteristics of Na+ -dependent citrate transport in primary cultures of neurons from mouse cerebral cortex and established the molecular identity of this transport system as the Na+ -coupled citrate transporter (NaC2/NaCT). Reverse transcriptase (RT)-PCR and immunocytochemical analyses revealed that only NaC2/NaCT was expressed in mouse cerebrocortical neurons but not in astrocytes. Uptake of citrate in neurons was Na+ -dependent, Li+ -sensitive, and saturable with the Kt value of 12.3 microM. This Kt value was comparable with that in the case of Na+ -dependent succinate transport (Kt = 9.2 microM). Na+ -activation kinetics revealed that the Na+ -to-citrate stoichiometry was 3.4:1 and concentration of Na+ necessary for half-maximal activation (K0.5(Na)) was 45.7 mM. Na+ -dependent uptake of [14C]citrate (18 microM) was significantly inhibited by unlabeled citrate as well as dicarboxylates such as succinate, malate, fumarate, and alpha-ketoglutarate. This is the first report demonstrating the molecular identity of the Na+ -coupled di/tricarboxylate transport system expressed in neurons as NaC2/NaCT, which can transport the tricarboxylate citrate as well as dicarboxylates such as succinate, alpha-ketoglutarate, and malate.

Animals↗
PubMed2006

Tolerable infusion rate of citrate based on clinical signs and the electrocardiogram in conscious dogs.

BACKGROUND & AIMS: The possible clinical significance of the toxic effects of citrate has not yet been fully clarified. This study was therefore conducted to confirm the toxicity and determine the tolerable infusion rate of citrate administered by rapid intravenous infusion to conscious dogs. METHODS: Citrate solutions were infused via the cephalic vein of 4 conscious dogs at 0.33, 0.67, or 1.33mmol/kg/h up to 1.33mmol/kg. Clinical signs and the electrocardiogram were observed during and after infusion. Serum citrate and ionized calcium levels were also measured. RESULTS: Although the mean citrate level increased in accordance with the infusion rate, the calcium level decreased. No significant changes in clinical signs or the electrocardiogram were observed during infusion at 0.33mmol/kg/h despite an increase in the serum citrate level to 1.22+/-0.11mmol/l (pre-infusion value: 0.38+/-0.01mmol/l) and a decrease in the serum calcium level to 1.28+/-0.03mmol/l (pre-infusion value: 1.50+/-0.05mmol/l). Vomiting and QTc prolongation were observed at 0.67mmol/kg/h or higher. Salivation and tachycardia were observed at 1.33mmol/kg/h. CONCLUSIONS: Based on clinical signs and the electrocardiogram, the tolerable infusion rate of citrate in conscious dogs is concluded to be 0.33mmol/kg/h.

Animals↗
PubMed2005

Spectroscopic studies of aqueous gallium(III) and aluminum(III) citrate complexes.

Aqueous gallium(III) citrate complexes have been studied in the 10(-2) M concentration range with extended X-ray absorption fine structure (EXAFS) and FTIR techniques. From EXAFS data, one mononuclear and one oligomeric species were identified at different Ga(III) to citrate ratios. The first shell of the mononuclear complex was found to be distorted, with average Ga-O bond lengths of 1.95 and 2.06 A, in agreement with the solid-state structure of Ga(Cit)2(3-) (Cit=citrate). Also the oligomeric species was found to have a distorted first shell, with average Ga-O bond lengths of 1.95 and 2.04 A. This complex was found to contain two Ga-Ga distances at 3.03 and 3.56 A, typical for edge and corner sharing GaO6 octahedra, respectively. The gallium(III) and aluminum(III) citrate systems were compared by means of FTIR, and were found to be analogous. The IR results suggest that the bond lengths derived from EXAFS for the 1:2 gallium(III) citrate complex also provide a good estimate of the corresponding distances in the mononuclear 1:1 complex. Direct coordination of citrate to the metal ions in the oligomeric gallium(III) citrate complex was indicated from both EXAFS and IR results, and this complex is stoichiometrically analogous to the Al3(H-1Cit)3(OH)(H2O)4- complex, which has been structurally determined. However, while the formation of the aluminum trimer has been shown to be slow, the gallium trimer was significantly more labile with a rate of formation indicated to be in the order of seconds or faster.

Journal Article↗
PubMed2003

The citrate carrier CitS probed by single-molecule fluorescence spectroscopy.

A prominent region of the Na(+)-dependent citrate carrier (CitS) from Klebsiella pneumoniae is the highly conserved loop X-XI, which contains a putative citrate binding site. To monitor potential conformational changes within this region by single-molecule fluorescence spectroscopy, the target cysteines C398 and C414 of the single-Cys mutants (CitS-sC398, CitS-sC414) were selectively labeled with the thiol-reactive fluorophores AlexaFluor 546/568 C(5) maleimide (AF(546), AF(568)). While both single-cysteine mutants were catalytically active citrate carriers, labeling with the fluorophore was only tolerated at C398. Upon citrate addition to the functional protein fluorophore conjugate CitS-sC398-AF(546), complete fluorescence quenching of the majority of molecules was observed, indicating a citrate-induced conformational change of the fluorophore-containing domain of CitS. This quenching was specific for the physiological substrate citrate and therefore most likely reflecting a conformational change in the citrate transport mechanism. Single-molecule studies with dual-labeled CitS-sC398-AF(546/568) and dual-color detection provided strong evidence for a homodimeric association of CitS.

Bacterial Proteins↗
PubMed1998

Citrate inhibition of snake venom proteases.

Thirty snake venoms had a citrate content of 2.3 to 12.9%, dry basis, by an aconitase isocitric dehydrogenase coupled enzyme assay. This is a venom concentration range of approximately 30 to 150 mM citrate assuming 25% venom solids content. Inhibition of snake venom protease activity by the addition of exogenous citrate was obtained using azure blue hide powder and azocasein as substrates. Protease inhibitions of 7.5% for Crotalus atrox venom to 78% for Bothrops picadoi venom were observed with citrate. Complete inhibition of snake venom protease activity by citrate was not observed. Bothrops asper (Pacifico) venom showed a 41% protease inhibition by citrate with azocasein as the substrate and 46% inhibition of Bothrops asper (Alantico) venom protease with azure blue hide power as a substrate. Trypsin was not inhibited in this system. Citrate may inhibit some venom protease activity by forming a complex with the zinc of zinc-dependent enzymes. reserved.

Animals↗
PubMed2000

Effect of a neutral citrate solution on the fluoride release of resin-modified glass ionomer and polyacid-modified composite resin cements.

The effect of 0.01 mol/l citrate solution at pH = 7 on the fluoride release is compared for the resin-modified glass ionomer cements (RM-GIC) GC Lining LC, PhotacBond, Vitremer and Vitrebond and for the polyacid-modified composite resins (PAM-C) Variglass and Dyract by means of the six-month fluoride release profiles at 37 degrees C. The fluoride release of both RM-GIC and PAM-C increases in the neutral citrate solution as compared to water, which can be explained by the ability of citrate to complex metal ions and hence to degrade the glass as well as the polysalt matrix of the cement. Although RM-GIC release more fluoride than PAM-C in water as well as in citrate solution, the relative increase in fluoride release upon immersion in citrate solution is most pronounced for PAM-C. Whereas for the latter citrate affects both the short-term and long-term fluoride release, for RM-GIC only the long-term fluoride release is affected. This suggests that the action of citrate increases with decreasing importance of the polysalt formation in the hardening of the material. This could be explained on the basis of the difference in the chemical properties of the cement matrix.

Acrylic Resins↗
PubMed1998

Gastrointestinal absorption of aluminium and citrate in man.

Aluminium (Al) is an abundant terrestrial element, but toxic to tissues, including brain. The body is largely protected because systemic Al absorption is very low and in normal individuals almost all absorbed Al is excreted from the body. However gastrointestinal (Gl) absorption is enhanced by organic acids, including citrate. Aluminium and citrate Gl absorption was measured in three healthy males, aged 40-46. After overnight fast, subjects drank a 100 ml fruit drink containing 280 mg Al and 3.2 g citrate (104 and 167 mM, respectively). Al was measured in timed blood and urine samples by GFAAS and serum citrate by enzymatic assay. Blood Al peaked by an increase of 13 +/- 2.1 micrograms/l after 87 +/- 19 min then fell slowly over 24 h. Plasma citrate peaked after 32 min, returning to baseline by 90 min. Al was excreted at a constant rate for the first 24 h, 0.4% of the dose being excreted in urine by this time. It is unlikely that Al is absorbed as Al citrate because the blood citrate peak preceded the Al peak by 45-60 min.

Administration, Oral↗
PubMed1997

Synthesis of citrate from phosphoenolpyruvate and acetylcarnitine by mitochondria from rabbit enterocytes: implications for lipogenesis.

Enterocytes from fasted rabbits make glucose from exogenous fructose and dihydroxyacetone at rates of 180 and 91 nmol/min/10(8) cells but do not make glucose from glycerol, aspartate, malate, lactate, alpha-ketoglutarate, glutamate or glutamine. Total activities of phosphoenolpyruvate carboxykinase, fructose 1,6-bisphosphatase and glucose 6-phosphatase in isolated enterocytes are 0.44, 0.60 and 1.90 mumol/min/10(8) cells, and > or = 95% of carboxykinase activity is intramitochondrial. Enterocytes contain marginal glycerol kinase (0.05 mumol/ min/10(8) cells) and essentially no pyruvate carboxylase activities. Enterocyte mitochondria synthesize citrate from exogenous phosphoenolpyruvate and acetylcarnitine at a rate of 2.40 nmol/min/mg protein. Citrate formation is highly dependent on exogenous HCO3 and inhibited strongly by 3-mercaptopicolinate and 1,2,3-benzenetricarboxylate. Citrate synthesis is stimulated consistently by GDP and significantly so by GTP. Citrate production is unaffected by ADP or ATP. Enterocytes from fasted-refed rabbits contain activities of 0.05, 0.12, 0.39 and 0.56 mumol/min/mg cytosolic protein of ATP:citrate lyase, NADP:malate dehydrogenase, glucose 6-phosphate dehydrogenase and NADP:isocitrate dehydrogenase. Activities of NADP:malate dehydrogenase, glucose 6-phosphate dehydrogenase and NADP:isocitrate dehydrogenase are significantly higher in enterocytes from fasted-refed rabbits than those from fasted rabbits. Mitochondrial phosphoenolpyruvate carboxykinase in enterocytes in vivo could convert glycolysis-derived phosphoenolpyruvate to oxaloacetate that, with acetyl CoA, could form citrate for export to support cytosolic lipogenesis as an activator of acetyl CoA carboxylase, a source of carbon via ATP:citrate lyase and of NADPH via NADP:malate dehydrogenase or NADP:isocitrate dehydrogenase.

Acetylcarnitine↗
PubMed2000

Silica xerogel carrier material for controlled release of toremifene citrate.

Sol-gel processed silica xerogel was used as a carrier material for toremifene citrate in order to develop an implantable controlled release formulation which could be localised to a desired site providing targeted and long-lasting disease control and resulting in a reduced amount of drug needed. Toremifene citrate, an anti-estrogenic compound, was incorporated into silica xerogel matrixes during polycondensation of organic silicate, tetraethyl ortho silicate (TEOS). The effects of drug amount, drying temperature and polyethylene glycol (PEG) on the release rate of toremifene citrate and degradation of the silica xerogel matrixes were investigated. Addition of PEG (M(w) 4600/10000) decreased the specific surface area of the matrix and lowered the release rate of the drug. Reducing the amount of drug in the matrix also decreased the release rate of toremifene citrate. However, drying temperature did not affect the release rate of silica or toremifene citrate. The release profiles of toremifene citrate were according to zero order kinetics, suggesting that drug release was controlled by erosion of the silica xerogel matrix. These results suggest that the toremifene citrate release rate can be controlled to some extent by adding (PEG) or by varying the amount of drug in the silica xerogel matrix.

Delayed-Action Preparations↗
PubMed1999

Cloning and sequencing of the chromosomal DNA and cDNA encoding the mitochondrial citrate synthase of Aspergillus niger WU-2223L.

The complementary DNA (cDNA) and chromosomal DNA encoding the citrate synthase (EC 4.1.3.7) gene (cit1) of Aspergillus niger WU-2223L, a citric acid-producing strain, were cloned. Synthetic oligonucleotide primers were designed according to the amino acid sequences of already known eukaryotic citrate synthases and the codon bias of A. niger genes. The 920-bp DNA fragment was amplified by polymerase chain reaction with these primers using chromosomal DNA of WU-2223L as a template, and was employed to screen a cDNA library of A. niger. One full-length cDNA clone was isolated and sequenced, within which an ORF of 1425 by encoding a protein of 475 as with a molecular weight of 52,153 Da was found. Its N-terminal region contains a typical mitochondrial-targeting motif. The predicted as sequence was 82, 68, and 65% homologous with the mitochondrial citrate synthases of Neurospora crassa, Saccharomyces cerevisiae, and pig, respectively, but it showed lower homology to bacterial citrate synthases. The full-length cDNA clone was used to screen a chromosomal library of A. niger WU-2223L, and a 7.5 kb-SalI fragment containing the corresponding chromosomal gene was isolated. Comparison of the chromosomal and cDNA sequences revealed that the cit1 gene is interrupted by six introns. In the chromosomal DNA, upstream of the coding region, a CT-rich region, but not the TATAAA or CAAT motifs, was found. Escherichia coli MOB150, a citrate synthase-deficient mutant showing a glutamate-requiring phenotype, was transformed with the plasmid pKAC-35S, which is the expression vector pKK223-3 containing the cDNA fragment encoding a putative mature protein of A. niger citrate synthase. The transformant harboring pKAC-35S showed citrate synthase activity and a glutamate-nonrequiring phenotype.

Journal Article↗
PubMed1998

Citrate, calcium, phosphate and magnesium in sows' milk at initiation of lactation.

Colostrum and milk were collected from ten sows at frequent intervals from before farrowing until 9 d after farrowing. Ionized calcium, pH, and total concentrations of citrate, calcium, phosphate and magnesium were measured in whole milk. The diffusible fraction of the mammary secretion was separated by ultrafiltration and was used for the measurement of diffusible citrate, calcium, phosphate and magnesium. The pH before farrowing was 5.7, and increased to 6.5 on day 4 as total calcium and phosphate also increased. Before farrowing, total and diffusible citrate were 7.8 and 7.3 mM respectively, while diffusible phosphate was 11.9 mM, and these concentrations all decreased during the study period. Total magnesium ranged between 3.3 and 4.1 mM, while diffusible magnesium ranged between 2.0 and 3.1 mM. While these concentrations and patterns of change of diffusible calcium and citrate are quite different from those of women's milk during the first week after birth, theoretical physicochemical relationships between diffusible calcium and citrate, and ionized calcium and HPO4(2-) were corroborated by these results. We conclude that diffusible citrate plays an important role in the determination of the concentration of diffusible calcium. However, while citrate may be the major determinant of the total concentration of calcium in women's milk, this is not the case in sows' milk.

Animals↗
PubMed1998

Cardiac accumulation of citrate during brief myocardial ischaemia and reperfusion in the pig in vivo.

Citrate is a key intermediate in energy metabolism and an inhibitor of phosphofructokinase of the glycolytic pathway. During myocardial ischaemia glycolysis is the main source of cardiac ATP. The aim of the present study was to determine if myocardial ischaemia and reperfusion alter cardiac tissue levels of citrate. Open-chest, anaesthetized pigs were subjected to 10 min of regional myocardial ischaemia by occlusion of the left anterior descending coronary artery, with and without reperfusion, and to 10 min of global ischaemia by circulatory arrest. Citrate, amino acids, glucose and NH3 were measured in biopsies. Ischaemia, whether regional or global, caused a 60-70% increase in tissue levels of citrate. During 1 min of reperfusion following regional ischaemia the level of citrate increased 460%, to approximately 600 nmol g-1 wet weight. The level of glutamate decreased by 20-33% (corresponding to 1300-2200 nmol g-1 wet weight), indicating net consumption of this amino acid during ischaemia. The level of aspartate decreased 50% indicating conversion of aspartate to oxaloacetate for the synthesis of citrate. Theoretically, the accumulation of myocardial citrate during brief ischaemia and early reperfusion is large enough to significantly inhibit phosphofructokinase activity and could therefore affect the ability of the myocardium to increase the glycolytic rate in response to ischaemia. This could, however, be partly compensated by the metabolism of myocardial glutamate.

Amino Acids↗
PubMed2001

Comparison of 1-week vs. 2- or 4-week therapy regimens with ranitidine bismuth citrate plus two antibiotics for Helicobacter pylori eradication.

BACKGROUND: Helicobacter pylori eradication therapies based on ranitidine bismuth citrate have recently been introduced in clinical practice. AIM: To compare the efficacy of three regimens containing ranitidine bismuth citrate given for 1, 2 and 4 weeks, combined with two antibiotics for the first week, in the eradication of H. pylori. METHODS: Eighty-six consecutive patients (50 duodenal ulcer disease, 36 non-ulcer dyspepsia) with H. pylori infection were offered three eradication regimens: (a) 1-week group (n=28), ranitidine bismuth citrate 400 mg b.d. for 7 days; (b) 2-week group (n=29), ranitidine bismuth citrate 400 mg b.d. for 14 days; and (c) 4-week group (n=29), ranitidine bismuth citrate 400 mg b.d. for 28 days. In all patients, clarithromycin 500 mg b.d. and metronidazole 500 mg b.d. were given for the first week. Endoscopy was repeated 1 month after the end of treatment and eradication was considered to be successful if both rapid urease test and histology were negative. RESULTS: Overall, H. pylori was eradicated in 84% (72/86) patients on intention-to-treat analysis, whereas the per protocol cure rate was 89% (72/81). Eradication rates were 23/27 (85%) (95% confidence interval (CI): 66-96%), 25/27 (92%) (95% CI: 76-99%) and 24/27 (89%) (95% CI: 71-98%) in the 1-, 2- and 4-week groups, respectively, on per protocol analysis, and 25/28 (82%) (95% CI: 63-94%), 25/29 (86%) (95% CI: 68-96%) and 24/29 (83%) (95% CI: 64-94%), respectively, on intention-to-treat analysis (P > 0.05, N.S.). No significant differences were observed between groups concerning duodenal ulcer healing, resolution of symptoms and adverse effects. CONCLUSIONS: The 1-week regimen with ranitidine bismuth citrate, clarithromycin and metronidazole is effective in H. pylori eradication. Prolongation of treatment with ranitidine bismuth citrate for 2 or 4 weeks does not achieve a statistically significant more favourable outcome.

Adult↗
PubMed2001

One-week regimens containing ranitidine bismuth citrate, furazolidone and either amoxicillin or tetracycline effectively eradicate Helicobacter pylori: a multicentre, randomized, double-blind study.

BACKGROUND: The metronidazole resistance of Helicobacter pylori strains has increased rapidly. AIM: To evaluate the efficacy and safety of new 1-week regimens containing ranitidine bismuth citrate, furazolidone and either amoxicillin or tetracycline. METHODS: One hundred and twenty patients with H. pylori-positive inactive duodenal ulcer or non-ulcer dyspepsia diagnosed by endoscopy were recruited randomly to receive one of two regimens for 7 days: ranitidine bismuth citrate, 350 mg b.d., furazolidone, 100 mg b.d., and either amoxicillin, 1000 mg b.d. (n=60), or tetracycline, 500 mg b.d. (n=60). H. pylori infection was identified by rapid urease testing and histology. 13C-Urea breath test was performed to evaluate the cure of H. pylori infection at least 4 weeks after completion of triple therapy. RESULTS: The eradication rates of H. pylori by ranitidine bismuth citrate-furazolidone-amoxicillin and ranitidine bismuth citrate-furazolidone-tetracycline regimens were 82% and 85% (P > 0.05), respectively, by intention-to-treat analysis, and 85% and 91% (P > 0.05), respectively, by per protocol analysis. Adverse effects were mild in both ranitidine bismuth citrate-furazolidone-amoxicillin and ranitidine bismuth citrate-furazolidone-tetracycline groups. CONCLUSIONS: One-week regimens containing ranitidine bismuth citrate, furazolidone and amoxicillin or tetracycline are well tolerated and effective for the eradication of H. pylori.

Adolescent↗
PubMed1997

Citrate metabolism by human platelets.

As part of a study on the utilization of substrates by platelets in defined media the metabolism of citrate was measured, since citrate is a common anticoagulant of nearly all such media, and is also an intermediate of oxidative metabolism. Human platelets transferred from plasma to an artificial medium by gel filtration, were incubated with [14C]citrate at 22 degrees C and labelled carbon dioxide produced was measured during short-term incubations of 2 h. Citrate (1 mM) was oxidized to carbon dioxide at low (0.3 nmol per 10(9) platelets h-1) but significant rates, and the oxidation was decreased by the presence of an alternative substrate (acetate) in the medium. There was, however, no significant conversion of citrate to glycogen. It was calculated that under normal storage conditions of platelet concentrates for transfusion purposes, the amount of citrate used cannot decrease citrate concentrations sufficiently to bring about platelet activation.

Blood Platelets↗