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Biomedical subjects

Y Fischer

Publications and source records attributed to Y Fischer.

At least 19 recordsLinked to original sources
PubMed2006

[Long term change in quality of life after adenotonsillectomy for pediatric obstructive sleep disorders].

BACKGROUND: To study short-term and long-term changes in quality of life (QOL) in children before and after adenotonsillectomy (T and A) for obstructive sleep disorders (OSDs). MATERIALS AND METHODS: Prospective study of 20 children underwent T and A for OSDs at the University hospital of Ulm/Germany. Caregivers were asked to complete the Brouillette-Score (BS) and OSA-18 survey, validated instruments for detecting symptoms and QOL change in children with OSDs, at the initial office visit prior to surgery (BS/1 and OSA-18/1) within 7.5 +/- 1.14 weeks after surgery (BS/2 and OSA-18/2), and 14.8 +/- 1.98 months after surgery (BS/3 and OSA-18/3). The BS comprises 3 items including: difficulty breathing during sleep, apnea observed by the caregivers and snoring. The OSA-18 survey comprises 18 items in 5 domains of sleep disturbance, physical suffering, emotional distress, daytime problems, and caregiver concerns. Scores from the preoperative and postoperative surveys were compared using the paired T-test and SPEARMAN-RANK test. RESULTS: 13 children were male (65 %). The mean age at the time of inclusion in the study was 6.2 +/- 1.63 years, mean preoperative body mass index (BMI) was 17.4 +/- 1.24 kg/m(2). Brouillette-Score: The mean Brouillette-Score before T and A (2.72) was significantly higher ( P = or < .001) than in the short-term (- 2.19) and in the long-term. (- 3.54). OSA-18 SURVEY: The mean total score for OSA-18/1 (83.4) was significantly higher ( P = or < .001) than the mean total score for OSA-18/2 (29.8) and OSA-18/3 (25.6). The overall correlation between BS and OSA-18 was R = .887 ( P = or < .001). CONCLUSION: Children with suspicious OSDs demonstrate significant short term and long-term improvement in the Brouillette-Score and OSA-18 survey. Caregivers perceive a long-term improvement for a minimum of one year in QOL after T and A for OSDs, although these improvements are not uniform across all domains of the OSA-18 survey. Use of the Brouillette-Score and the OSA-18 survey should decrease the need for polysomnographic monitoring and facilitate selection of children for T and A, whereas the OSA-18 questionnaire permits the more differentiated finding.

Adenoidectomy↗
PubMed2006

[Examiner variability of clinical findings in patients with sleep related breathing disorders].

BACKGROUND: Clinical findings in sleep related breathing disorders (SRBD) and primary snoring are not only of diagnostic but also of therapeutic relevance because clinical findings may be used for the selection of surgical interventions such as uvulopalatopharyngoplasty (UPPP), maxillofacial surgery or radiofrequency induced surgical alternatives. We developed a standardized protocol for clinical examination of the upper airway using pictograms. MATERIAL AND METHODS: To determine the interinvestigators variability various parameters such as length of the uvula, position of tongue base, Angle-classification, webbing of posterior pillar and tonsil size were assessed by a number of residents and an assistant professor for Otorhinolaryngology and sleep medicine simultaneously. RESULTS: 95 patients (81 male and 14 female) with a mean age of 47.0 +/- 1.21 years, a Body-Mass-Index (BMI) of 27.2 +/- 0.46 kg/m2, and an Apnea-Hypopnea-Index (AHI) of 17.7 +/- 2.4 were examined. The appearance of the uvula has only little variations between different investigators (corr.: 0.943). The interinvestigator variability is also low for position of tongue base (corr.: 0.931) and Angle-classification (corr.: 0.893). The results of tonsil size and webbing assessment seems to have a higher variability (corr.: 0.880 and 0.693). Statistical significance for all parameters was p=<0.0001. CONCLUSION: As to our knowledge, this is the first controlled study to record intraobserver variations of clinical findings of the upper airway. Standardized protocols are mandatory, and the variability of the measurements must be taken into account if results of different investigations must be compared or if changes after therapeutic interventions are to be investigated.

Adult↗
PubMed2005

An autologous system for culturing head and neck squamous cell carcinomas for the assessment of cellular therapies on the chorioallantois membrane.

The evaluation of novel immunotherapeutic anti-cancer strategies requires target and effector cells from the autologous host to avoid false positive results because of allo-reactivity. Head and neck squamous cell carcinoma cells (HNSCC) do not proliferate under standard culture conditions in plastic ware. To create an autologous model, the chorioallantois membrane (CAM) of chicken embryos was employed to culture HNSCC and peripheral blood mononuclear cells (PBMC). Separated tumor cells were co-incubated with a cytostatic agent, PBMC, or mere cell culture medium as a control. Tumor cell lysis was assessed by acridine orange staining or by flow cytometry analysis of iodide marked cells after 24 and 48 h of co-incubation. Incubation with cisplatin resulted in a decrease of viable cells by 49% after 24 h and 48 h. In contrast, incubation with mere culture medium resulted in an increase of viable tumor cells by 5% after 24 h and a decrease of 4% after 48 h; the incubation of tumor cells and PBMC led to a non-significant decrease by 14% after 24 h and 16% after 48 h. Taken together, the CAM supports a favorable environment for the co-culture of HNSCC and PBMC, thus providing an approximated in vivo autologous model to assess the efficacy of new cell-therapeutical approaches.

Animals↗
PubMed2005

[Sleep-related breathing disorders. Sleep anamnesis questionnaire and determination of clinical results within the framework of staged diagnostics].

Sleep-related breathing disorders (SBAS) affect approximately 8% of the population of middle aged adults. At the age of 20 years, approximately 10% of the population snore, while at the age of 60 about 50% of men snore. Some 9% of middle aged women and 24% of middle aged men have an apnea hypopnea index (AHI) of >5 (number of nocturnal apnea and hypopnea per hour of sleep). Sleep apnea hypopnea syndrome is found in 2% of the women and 4% of the men, i.e. they have an AHI>5 associated with daytime sleepiness. Forms, check lists, summaries and patient-readable questionnaires have proved helpful in the evaluation of SBAS.

Adult↗
PubMed2004

The use of an ambulatory, automatic sleep recording device (QUISI version 1.0) in the evaluation of primary snoring and obstructive sleep apnoea.

Electroencephalogram (EEG) evaluation with polysomnography (PSG) according to the Rechtschaffen & Kales (R&K) rules is time and cost consumptive, but ambulatory polygraphy systems do not allow EEG recording routinely. As a consequence, the number of sleep disordered events cannot be calculated exactly. QUISI is a one-channel, self-applicable ambulatory EEG recording device. The present study was designed as a prospective, non-randomized clinical trial. This investigation evaluated the results of 40 patients with primary snoring and obstructive sleep apnoea measured with level 1 PSG and QUISI simultaneously. Fifteen patients (37.5%) were primary snorers with normal sleep profiles, whereas 25 patients (62.5%) suffered from obstructive sleep apnoea (OSA) with a Respiratory Disturbance Index (RDI) of 38.6 +/- 23.8. The mean total sleeping time (TST) was underestimated by 4.5%, while Sleep Efficiency Index (SEI) was understimated by 4.6% by the QUISI device compared with PSG. The correlation between the QUISI and the PSG estimates for single sleep stages demonstrated only moderate correlation. The statistical significance for sleep stage 2 was r = 0.42, P = 0.002; for sleep stage 3/4, r = 0.31, P = 0.02; and for WAKE, r = 0.33, P = 0.01. Sleep stage 2 as well as sleep stage 3/4 were underestimated by QUISI substantially (difference: -5.6% and -10.3%), while WAKE was overestimated by QUISI to a larger amount (difference: +10.4%). Sensitivity and specificity of QUISI to recognize pathological sleep profiles compared with PSG/R&K were 0.92 and 0.96 respectively. QUISI is able to evaluate normal versus altered sleep profiles in patients with primary snoring and OSA. Comparing the quartile ranges, we found substantial differences between QUISI and PSG/R&K. QUISI gives an impression of sleep architecture and objective verification of a sleep disturbance in an ambulant setting but cannot replace the sleep laboratory-based PSG.

Adult↗
PubMed2003

[Prevalence of obstructive sleep apnea syndrome (OSA) in patients with sudden hearing loss. A pilot study].

BACKGROUND: It is estimated that in patients with sleep-related breathing disorders the probability of a cerebral vascular infarction (CVI) is 3.1 times that in patients without sleep apnea and that 25-50% of all patients who have a stroke suffer from sleep apnea (OSA) and have a respiratory disturbance index (RDI) higher than 10. CVI may be caused by variations in intracranial pressure or in intracranial hemodynamics owing to decreasing pO(2) and increasing pCO(2) during cessation of airflow. It is suspected that the most common causes of sudden deafness are vasospasm, thrombosis, embolism, hypercoagulation and sludging. The present study analyzed the prevalence of sleep apnea in patients with sudden hearing loss. PATIENTS AND METHODS: A 7-channel polygraph was used to test 33 subjects with normal hearing and 27 patients suffering from sudden hearing loss. Statistical analyses were performed with a Chi-square test and the Mann-Whitney test. RESULTS: We found that 29.6% of the patient group and 21.2% of those in the study control group were suffering from OSA and had RDI >10; this difference was not significant ( p=0.554). Sudden hearing loss may also be an indicator of arteriosclerosis secondary to such risk factors as hypertension ( p=0.005), diabetes ( p=0.003), and hyperlipidemia ( p=0.004), which were highly significant for the patient group. CONCLUSION: Patients who develop sudden hearing loss tend to have OSA more frequently than those in the control group owing to the similar risk factors for cerebral infarction and sudden hearing loss.

Adolescent↗
PubMed2001

Inhibition of glucose transport by cyclic GMP in cardiomyocytes.

Recent evidence points to a potential role of cyclic GMP (cGMP) in the control of cardiac glucose utilization. The present work examines whether the glucose transport system of cardiac myocyte is a site of this cGMP-dependent regulation. Treatment of isolated rat cardiomyocytes (for 10 min) with the membrane-permeant cGMP analogue 8-(4-chlorophenylthio)-cGMP (8-p-CPT-cGMP, 200 microM) caused a decrease in glucose transport in non-stimulated (basal) myocytes, as well as in cells stimulated with insulin or with the mitochondrial inhibitor oligomycin B by up to 40%. An inhibitory effect was also observed with another cGMP analogue (8-bromo-cGMP), and in cells stimulated by hydrogen peroxide or anoxia. In contrast, 8-p-CPT-cAMP (200 microM), or the beta-adrenergic agonist isoprenaline (which increases cAMP levels) did not depress glucose transport, and even potentiated the effect of insulin. Blockade of endogenous cGMP formation with the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 microM) significantly increased basal and insulin-dependent glucose transport (by 25%), whereas addition of the guanylate cyclase activator 3-(5'-hydroxymethyl-2'furyl)-1-benzylindazol (YC-1, 30 microM) produced a depression of glucose transport (by 20%). Confocal laser scanning microscopic studies revealed that cGMP partially prevents the insulin-induced redistribution of the glucose transporter GLUT4 from intracellular stores to the cell surface. These observations suggest that the glucose transport system of cardiomyocytes represents a metabolic target of inhibition by cGMP, and that this regulation occurs at the level of the trafficking of glucose transporters.

Animals↗
PubMed2001

Heart-type fatty acid binding protein (hFABP) in the diagnosis of myocardial damage in coronary artery bypass grafting.

OBJECTIVES: Heart-type fatty acid binding protein (hFABP) is an intracellular molecule engaged in the transport of fatty acids through myocardial cytoplasm and has been used as a rapid marker of myocardial infarction. However, its value in the evaluation of perioperative myocardial injury has not yet been assessed. METHODS: 32 consecutive patients undergoing coronary artery bypass grafting were included in a prospective, randomized study using standardized operative procedures and myocardial protection. Three patients with perioperative myocardial infarction were added. Serial blood samples were taken preoperatively, before ischemia, 5 and 60 min after declamping, 1 and 6 h postoperatively and on postoperative days 1, 2 and 10 and were tested for hFABP, creatine kinase isoenzyme MB (CKMB) and troponin I (TnI). RESULTS: Hospital mortality was zero. The kinetics of the biochemical parameters revealed a typical pattern for each marker. In routine patients, hFABP levels peaked as early as 1 h after declamping, whereas CKMB and TnI peaked only 1 h after arrival in the intensive care unit. Patients with perioperative infarction displayed peak levels some hours later in all marker proteins. Peak serum levels of hFABP correlated significantly with peak levels of CKMB (r=0.436, P=0.011) and TnI (r=0.548, P=0.001), indicating the degree of myocardial damage. CONCLUSIONS: hFABP is a rapid marker of perioperative myocardial damage and peaks earlier than CKMB or TnI. The kinetics of marker proteins in serial samples immediately after reperfusion is more suitable for the detection of perioperative myocardial infarction than a fixed cut-off level.

Biomarkers↗
PubMed2001

The endosomal compartment is an insulin-sensitive recruitment site for GLUT4 and GLUT1 glucose transporters in cardiac myocytes.

In nonstimulated cardiomyocytes, the glucose transporter GLUT4 is confined to intracellular vesicles forming at least two populations: a storage pool enriched in GLUT4 (pool 1) and an endosomal pool containing both GLUT4 and GLUT1 (pool 2). We have now studied the dynamics of these pools in response to insulin or the mitochondrial inhibitor rotenone in rat cardiomyocytes. Rotenone recruited GLUT4 and GLUT1 to the cell surface from endosomal pool 2 without affecting pool 1. Kinetic experiments were consistent with rotenone acting on an intracellular compartment that is in close connection with the plasma membrane. In contrast, insulin caused rapid, complete depletion of GLUT4 from pool 1 and reduced the GLUT1 content of pool 2 by approximately 50%, whereas, surprisingly, no net decrease in GLUT4 occurred in this pool. Subsequent insulin withdrawal resulted in slow replenishment of pool 2 with GLUT1 and of pool 1 with GLUT4. When pool 1 was still largely depleted of GLUT4, a second insulin challenge did reduce GLUT4 in pool 2 and stimulated glucose transport to the same extent as the first insulin treatment. In conclusion, the storage pool is the primary source of GLUT4 in response to insulin, but not to rotenone. In addition, the endosomal compartment is an important recruitment site of both GLUT1 and GLUT4 when the storage pool is either unaffected (rotenone) or depleted (by a previous insulin challenge). GLUT4 mobilized by insulin from the storage pool may pass through an intermediary (possibly endosomal) compartment on its way to the cell surface.

Animals↗
PubMed2001

Enhancing filtration rates by the use of blood flow around the capillaries of plasmafilters: an in vitro study.

As the low clearance rate of plasmaseparation limits its use in the treatment of patients suffering from liver failure, sepsis or MOF, we intend to develop strategies for a plasmaseparation unit which increases plasmafiltration rates. Our first question focused on whether commercially available plasmaseparation filters, and in particular their membranes, are suitable for the inversion of blood and plasma compartments. This experimental study was performed using in vitro systems. Commercially available plasmafilters PF2000N (Gambro) and Plasmaflo (Asahi) were compared in both their normal operating mode with blood flow through the capillary lumen, and in the inverse mode. Inverse mode means that blood flows through the outer space of the capillaries while plasma was obtained from the lumen. Heparinised porcine blood (5 I.U./ml) was used in a heated, recirculating in vitro circuit. Our main results were that the normal use of both filter types Plasmaflo and PF2000N enabled maximal blood flows (Qb) of 200 ml/min and filtration rates (Qf) of 25-40 ml/min. Operating the filters in the inverse mode enabled Qb up to 500 ml/min and Qf up to 100 ml/min. Hemolysis, platelet counts and coagulation parameters did not differ significantly regardless of whether the normal or inverse mode was used. The tested plasmafiltration membranes appear to be suitable for use in inverse mode. Although in our experiments, hemocompatibility tests did not indicate severe problems induced by the module geometry, the development of a module specially constructed for blood flow outside of the hollow fibers appears to be necessary in order to minimise shunts and low perfusion areas.

Animals↗
PubMed2000

[Radiofrequency ablation of the soft palate (somnoplasty). A new method in the treatment of habitual and obstructive snoring].

Twenty-nine patients (26 male and 3 female) with habitual or obstructive snoring and socially disturbing character were followed over a ten week period. All patients were treated with radiofrequency volumetric tissue reduction (RFVTR) of the soft palate. In 21 patients this operation was combined with other surgery of the upper airway, eight patients had soft palate reduction with RFVTR exclusively. With this method an electrode is positioned in the musculature of the soft palate submucosally. RFVTR may be performed under local anesthesia and has to be repeated if necessary. Ten weeks postoperatively 24 of 29 patients, respectively their social-partners, reported subjective reduction of snoring after the first treatment. Markable improvement of snoring was seen in 20 of 29 patients postoperatively and reduction of the respiratory-disturbance-index (RDI) for more than 10 was noticed in 7/29 patients polysomnographically. 5/8 patients who were treated with RFVTR exclusively, showed reduction of snoring and 3/8 patients had RDI-reduction for more than 10. We conclude, that RFVTR of the soft palate is successful in the treatment of snoring and may be helpful in the treatment of mild obstructive-sleep-apnea-syndrome (OSAS).

Aged↗
PubMed2000

Sudden onset of EDTA-dependent pseudothrombocytopenia after therapy with the glycoprotein IIb/IIIa antagonist c7E3 Fab.

The development of thrombocytopenia following exposure to the platelet glycoprotein (GP) IIb/ IIIa receptor antagonist abciximab (c7E3 Fab, ReoPro) is associated with adverse clinical outcome and excessive bleeding. Pseudothrombocytopenia is an important differential diagnosis in sudden onset of thrombocytopenia in a patient treated with c7E3 Fab. We report on a case of documented sudden onset of EDTA-dependent pseudothrombocytopenia in a 63-year-old woman who was admitted for emergency coronary intervention. Four hours after bolus administration of c7E3 Fab, the platelet concentration in EDTA-anticoagulated blood decreased from 385 x 10(9)/l to 119 x 10(9)/l, and it showed a further decrease to 57 x 10(9)/l at the end of a 12-h infusion. Despite no warnings or abnormalities of the automated cell counter, platelet aggregates were observed by microscopic evaluation of the blood smear. Repeated platelet counts in citrate-anticoagulated samples revealed platelet concentrations within the reference range. EDTA-dependent pseudothrombocytopenia due to therapy with c7E3 Fab is an important differential diagnosis that needs to be excluded rapidly from other causes of thrombocytopenia to avoid unnecessary further examinations, discontinuation of therapy, or even initiation of inappropriate therapy.

Abciximab↗
PubMed2000

Novel mechanism for presynaptic inhibition: GABA(A) receptors affect the release machinery.

Presynaptic inhibition is produced by increasing Cl(-) conductance, resulting in an action potential of a smaller amplitude at the excitatory axon terminals. This, in turn, reduces Ca(2+) entry to produce a smaller release. For this mechanism to operate, the "inhibitory" effect of shunting should last during the arrival of the "excitatory" action potential to its terminals, and to achieve that, the inhibitory action potential should precede the excitatory action potential. Using the crayfish neuromuscular preparation which is innervated by one excitatory axon and one inhibitory axon, we found, at 12 degrees C, prominent presynaptic inhibition when the inhibitory action potential followed the excitatory action potential by 1, and even 2, ms. The presynaptic excitatory action potential and the excitatory nerve terminal current (ENTC) were not altered, and Ca(2+) imaging at single release boutons showed that this "late" presynaptic inhibition did not result from a reduction in Ca(2+) entry. Since 50 microM picrotoxin blocked this late component of presynaptic inhibition, we suggest that gamma-aminobutyric acid-A (GABA(A)) receptors reduce transmitter release also by a mechanism other than affecting Ca(2+) entry.

Action Potentials↗
PubMed2000

Lower cardiac troponin T and I results in heparin-plasma than in serum.

BACKGROUND: The use of plasma rather than serum for determination of cardiac troponins can improve turnaround time and potentially avoid incomplete serum separation that may produce falsely increased results. We investigated the influence of incomplete serum separation and the effect of heparin-plasma on cardiac troponin concentrations. METHODS: Serum and heparin-plasma samples were drawn simultaneously from 100 patients (50 patients with acute coronary syndrome and 50 patients after open heart surgery) and measured on three different analytical systems, two for determination of cardiac troponin I (cTnI; Abbott AxSYM and Bayer ACS:Centaur) and one for cardiac troponin T (cTnT; Roche Elecsys cTnT STAT). Serum samples were reanalyzed after a second centrifugation to assess the influence of incomplete serum separation. RESULTS: Mean results (+/- 95% confidence interval) in heparin-plasma compared with serum were 101% +/- 2% (AxSYM cTnI), 94% +/- 3% (ACS:Centaur cTnI), and 99% +/- 3% (Elecsys cTnT). Differences >20% were seen in 11% of results on the ACS:Centaur, 9% of results on Elecsys cTnT, and 2% of results on the AxSYM. For the Elecsys cTnT assay, the magnitude of the difference between serum and plasma was independent of the absolute concentration and confined to individual samples, and was reversed by treatment with heparinase. A second centrifugation had no effect on serum results by any of the assays. CONCLUSION: The concentrations of troponins measured in heparin-plasma are markedly lower than in serum in some cases.

Acute Disease↗
PubMed1999

Activation of intrinsic hippocampal theta oscillations by acetylcholine in rat septo-hippocampal cocultures.

1. Oscillatory electro-encephalographic activity at theta frequencies (4-15 Hz) can be recorded from the hippocampus in vivo and depends on intact septal projections. The hypothesis that these oscillations are imposed on the hippocampus by rhythmically active septal inputs was tested using dual intracellular recordings from CA1 and CA3 pyramidal cells in septo-hippocampal cocultures. 2. Septo-hippocampal cocultures displayed spontaneous oscillatory synaptic activity at theta frequencies. In CA3 cells, EPSP/IPSP sequences predominated, whereas only EPSPs were apparent in CA1 cells. Synaptic potentials in CA3 cells preceded those in CA1 cells by 5-10 ms. 3. Oscillatory synaptic activity was blocked in cocultures by the muscarinic antagonist atropine (0.1 microM), facilitated but unchanged in frequency upon application of the acetylcholinesterase inhibitor neostigmine (1 microM), and not seen in hippocampal monocultures. 4. The muscarinic agonist methacholine (5-20 nM) induced oscillatory synaptic activity at 4-15 Hz in hippocampal monocultures, which was identical to that occurring spontaneously in septo-hippocampal cocultures. 5. Synaptic theta activity was observed in cocultures of septal tissue with subdissected hippocampal slices containing area CA3 alone, but not in septo-CA1 cocultures. 6. We conclude that oscillatory synaptic activity at theta frequencies, with similar characteristics to theta activity in vivo, can be generated by the hippocampal network in response to activation of muscarinic receptors by synaptically released acetylcholine from septal afferents. Furthermore, the oscillatory activity is determined by mechanisms intrinsic to the hippocampal circuitry, particularly area CA3. Rhythmic septal input is not required.

Acetylcholine↗
PubMed1999

Purinergic inhibition of glucose transport in cardiomyocytes.

ATP is known to act as an extracellular signal in many organs. In the heart, extracellular ATP modulates ionic processes and contractile function. This study describes a novel, metabolic effect of exogenous ATP in isolated rat cardiomyocytes. In these quiescent (i.e. noncontracting) cells, micromolar concentrations of ATP depressed the rate of basal, catecholamine-stimulated, or insulin-stimulated glucose transport by up to 60% (IC50 for inhibition of insulin-dependent glucose transport, 4 microM). ATP decreased the amount of glucose transporters (GLUT1 and GLUT4) in the plasma membrane, with a concomitant increase in intracellular microsomal membranes. A similar glucose transport inhibition was produced by P2 purinergic agonists with the following rank of potencies: ATP approximately ATPgammaS approximately 2-methylthio-ATP (P2Y-selective) > ADP > alpha,betameATP (P2X-selective), whereas the P1 purinoceptor agonist adenosine was ineffective. The effect of ATP was suppressed by the poorly subtype-selective P2 antagonist pyridoxal-phosphate-6-azophenyl-2', 4'-disulfonic acid but, surprisingly, not by the nonselective antagonist suramin nor by the P2Y-specific Reactive Blue 2. Glucose transport inhibition by ATP was not affected by a drastic reduction of the extracellular concentrations of calcium (down to 10(-9) M) or sodium (down to 0 mM), and it was not mimicked by a potassium-induced depolarization, indicating that purinoceptors of the P2X family (which are nonselective cation channels whose activation leads to a depolarizing sodium and calcium influx) are not involved. Inhibition was specific for the transmembrane transport of glucose because ATP did not inhibit (i) the rate of glycolysis under conditions where the transport step is no longer rate-limiting nor (ii) the rate of [1-14C]pyruvate decarboxylation. In conclusion, extracellular ATP markedly inhibits glucose transport in rat cardiomyocytes by promoting a redistribution of glucose transporters from the cell surface to an intracellular compartment. This effect of ATP is mediated by P2 purinoceptors, possibly by a yet unknown subtype of the P2Y purinoceptor family.

Adenosine Triphosphate↗