Disease relevance of Microelectrodes

• We used microelectrode techniques to study the indirect and direct actions of ouabain on human atrial fibers (HAF) obtained from patients with congenital heart disease undergoing open heart surgery [1].
• We used standard microelectrode techniques to evaluate the effects of lidocaine and quinidine on canine Purkinje fibers at normal pH (7.3) and in the presence of acidosis (pH 6.9) [2].
• High-resolution real-time recording with microelectrode biosensors reveals novel aspects of adenosine release during hypoxia in rat hippocampal slices [3].
• Glutamate release from the rat retina and intravitreal P(O2) profiles were monitored during and after ischemia with a microdialysis biosensor and oxygen-sensitive microelectrodes [4].
• 1. Intracellular pH (pHi) of cultured human airway epithelial cells from normal and cystic fibrosis (CF) subjects were measured with double-barrelled pH-sensitive liquid exchanger microelectrodes [5].

Psychiatry related information on Microelectrodes

• The glutamate dehydrogenase-modified microelectrode possesses a 300-ms response time with a detection limit of 0.5 mM glutamate and a 1-60 mM linear concentration range [6].
• In this work, dopamine release and uptake was measured in striatal slices from the R6/2 transgenic mouse model of Huntington's disease using fast-scan cyclic voltammetry at carbon-fiber microelectrodes [7].

High impact information on Microelectrodes

• Changes in transepithelial bioelectric properties and the permeability of the apical membrane to chloride in response to extracellular (apical) UTP were determined with ion-selective microelectrodes in cultured nasal epithelia [8].
• Until recently, intracellular free calcium has been amenable to measurement and investigation only in cells large enough to permit either microinjection of a suitable Ca sensor such as a aequorin or arsenazo III or insertion of a Ca-sensitive microelectrode [9].
• In microelectrode experiments acetylcholine (ACh), gastrin-cholecystokinin (CCK) as well as bombesin peptides evoked Ca2+-dependent opening of the K+ conductance pathway, resulting in membrane hyperpolarization [10].
• With the exception of the ion-sensitive microelectrodes developed for acetylcholine, these techniques are elaborate and time consuming, and cannot be routinely applied to every electrode used [11].
• Lithium accumulation by snail neurones measured by a new Li+-sensitive microelectrode [12].

Chemical compound and disease context of Microelectrodes

• METHODS: Spatial profiles of oxygen tension were obtained in the cat retina, in vivo, with the use of oxygen microelectrodes during control conditions and acute (5.19 +/- 0.83 hour) episodes of hyperglycemia (blood glucose, >350 mg/dL) [13].
• We examined the effects of hypoxia on the release of serotonin (5-HT) from intact neuroepithelial body cells (NEB), presumed airway chemoreceptors, in rabbit lung slices, using amperometry with carbon fibre microelectrodes [14].
• Changes in extracellular space (ECS) diffusion parameters in astrogliotic tissue around a unilateral cortical stab wound were determined from concentration-time profiles of tetramethylammonium (TMA(+)) using TMA(+)-selective microelectrodes [15].
• PURPOSE: Retinal prosthetic devices that use microelectrode arrays to stimulate retinal nerve cells may provide a viable treatment for degenerative retinal diseases [16].
• METHODS: As pericranial temperature was varied between 39 and 25 degrees C in normocapnic halothane-anesthetized rats, CMRG (using 14C-deoxyglucose) or the time to depolarization (using a glass microelectrode in the cortex) after a K(+)-induced cardiac arrest was measured [17].

Biological context of Microelectrodes

• Opening of these channels by diazoxide (100-250 mumol/liter) blocked the effects of glucose on B cell membrane potential (intracellular microelectrodes), free cytosolic Ca2+ (fura-2 method), and insulin release, but it did not prevent those of high K (30 mmol/liter) [18].
• METHODS AND RESULTS: Effects of three class III antiarrhythmic drugs, d,l-sotalol, E-4031, and MS-551, on the carbachol (1 mumol/L)-induced action potential shortening and outward K+ current were examined in guinea pig atrial cells by conventional microelectrode and patch clamp techniques [19].
• Angiogenesis, vessel diameter, blood flow rate, and vascular permeability were proportional to NO levels measured with microelectrodes: Wild-type (WT) > or = WT with l-NIL or iNOS(-/-) > eNOS(-/-) > or = eNOS(-/-) with l-NIL [20].
• The magnitude of CA release was highly correlated with the ocular dominance of neuronal activity measured with tungsten microelectrodes [21].
• Changes in retinal pigment epithelial (RPE) cell volume were measured by monitoring changes in intracellular tetramethylammonium (TMA) using double-barreled K-resin microelectrodes [22].

Anatomical context of Microelectrodes

• Accurate measurements of intracellular calcium activities in salivary gland epithelial cells of the insect Phormia regina were obtained with microelectrodes in which N,N'-di(11-ethoxycarbonyl)undecyl-N,N'-4,5-tetramethyl-3,6-dioxaoctane diacid diamide wsa incorporated in a liquid membrane system [23].
• The effects of thyrotropin-releasing hormone and 17 beta-estradiol on the electrical membrane properties of a prolactin-secretin pituitary cell line (GH3/B6) were studied with intracellular microelectrode recordings [24].
• A microelectrode continuously releasing cyclic adenosine monophosphate can divert the axis of the early chick embryo and attract cells on its ventral surface [25].
• Using microelectrode techniques, the electrical properties of the cell membranes and paracellular pathway of the surface epithelium in Necturus antrum were studied under control conditions and during exposure to mucosal solutions made hyperosmotic by addition of sucrose or urea [26].
• Regulation of intracellular pH in gastric epithelial surface cells exposed to luminal acid was investigated in isolated Necturus antral mucosa using microelectrode technique [27].

Associations of Microelectrodes with chemical compounds

• Calcium ion-selective microelectrodes made with Simon's neutral carrier were used to measure simultaneously sarcoplasmic Ca2+ activity (aiCa) and resting tension (Tr) of rabbit ventricular muscle during reduction and restoration of external sodium ion concentration, [Na]0 [28].
• The sodium-selective ligand 1,1,1-tris[1(1)-(2(1)-oxa-4(1)-oxo-5(1)-aza-5(1)-methyl)dodecanyl]propane dissolved in 3-nitro-o-xylene containing a small amount of the lipophilic anion tetrachlorophenyl borate was used as a liquid ion-exchanger in sodium-selective microelectrodes [29].
• Sensitive Clark-type O2 microelectrodes were inserted into renal cortex and medulla of anesthetized rats [30].
• Membrane electric potential difference (PD) and the responses to luminal Cl- replacement, isoproterenol, and amiloride were measured with intracellular microelectrodes [31].
• By cable analysis and intracellular microelectrode impalement in the in vitro perfused renal tubule, we identified alpha- and beta-intercalated (IC) cells along the rabbit distal nephron segments, including the connecting tubule (CNT), the cortical collecting duct (CCD), and the outer medullary collecting duct in the inner stripe (OMCDi) [32].

Gene context of Microelectrodes

• In the present study we applied patch-clamp whole-cell recordings and measurements of Ca(2+) concentration by ion-selective microelectrodes in eyes of normal and mutant Drosophila to isolate the TRP and TRP-like (TRPL)-dependent currents [33].
• The release of NO from NO-ASA, determined with a selective microelectrode was paralleled by the induction of NQO1 and abrogated by NO scavengers; an exogenous NO donor also induced the expression of NQO1 [34].
• We have examined electrophysiological properties of myelinated axons in hNF-H +/+ mice using intraaxonal microelectrode recording from isolated sciatic and tibial nerves [35].
• MCT1 activity was assessed by changes of intracellular H+ concentration measured by pH-selective microelectrodes during application of lactate [36].
• CONCLUSIONS: These data indicate that CA IX cannot be recommended as a substitute for oxygen microelectrode measurements [37].

Analytical, diagnostic and therapeutic context of Microelectrodes

• Extracellular alkaline transients, measured with pH-sensitive microelectrodes, were generated in the CA1 region of rat hippocampal slices by repetitive electrical stimulation of Schaeffer collateral fibers or by local ejection of glutamate [38].
• We examined this hypothesis in 11 patients with segmental and generalized dystonia undergoing microelectrode exploration of the internal globus pallidus (GPi) before pallidotomy or deep brain stimulation (DBS) implantation [39].
• Measurement of nutritive endoneurial blood flow by microelectrode polarography and hydrogen clearance showed 44% and 45% deficits for 1 and 2 months untreated diabetes (p < 0.001) that were prevented by ponalrestat and ZD5522 treatments, respectively [40].
• Postganglionic muscle sympathetic nerve traffic was recorded from the peroneal nerve at the fibular head with tungsten microelectrodes, and forearm blood flow was measured with venous occlusion plethysmography [41].
• Excitatory synaptic mechanisms associated with burst suppression activity were probed using glutamate receptor antagonists (CNQX and APV), GABA receptor antagonists, and simultaneous whole cell patch clamp and microelectrode EEG recordings [42].

References