keyword
MENU ▼
Read by QxMD icon Read
search

Current clamp

keyword
https://www.readbyqxmd.com/read/29456510/sodium-tanshinone-ii-a-sulfonate-ds-201-induces-vasorelaxation-of-rat-mesenteric-arteries-via-inhibition-of-l-type-ca-2-channel
#1
Xiao-Dong Zhang, Chun-Xia He, Jun Cheng, Jing Wen, Peng-Yun Li, Na Wang, Guang Li, Xiao-Rong Zeng, Ji-Min Cao, Yan Yang
Background: We previously have proved that sodium tanshinone II-A sulfonate (DS-201), a derivative of traditional Chinese medicinal herb Danshen (Salvia miltiorrhiza), is an opener and vasodilator of BKCa channel in the vascular smooth muscle cells (VSMCs). Vascular tension is closely associated with Ca2+ dynamics and activation of BKCa channel may not be the sole mechanism for the relaxation of the vascular tension by DS-201. Therefore, we hypothesized that the vasorelaxing effect of DS-20 may be also related to Ca2+ channel and cytoplasmic Ca2+ level in the VSMCs...
2018: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/29456141/inhomogeneous-encoding-of-the-visual-field-in-the-mouse-retina
#2
Rebekah A Warwick, Nathali Kaushansky, Nimrod Sarid, Amir Golan, Michal Rivlin-Etzion
Stimulus characteristics of the mouse's visual field differ above and below the skyline. Here, we show for the first time that retinal ganglion cells (RGCs), the output neurons of the retina, gradually change their functional properties along the ventral-dorsal axis to allow better representation of the different stimulus characteristics. We conducted two-photon targeted recordings of transient-Offα-RGCs and found that they gradually became more sustained along the ventral-dorsal axis, revealing >5-fold-longer duration responses in the dorsal retina...
February 9, 2018: Current Biology: CB
https://www.readbyqxmd.com/read/29454619/delineation-of-the-functional-properties-and-the-mechanism-of-action-of-aa29504-an-allosteric-agonist-and-positive-allosteric-modulator-of-gaba-a-receptors
#3
Emma Rie Olander, Nawid Madjroh, Lennart Bunch, Pella Cecilia Söderhielm, Anders A Jensen
The retigabine analog 2-amino-4-(2,4,6-trimethylbenzylamino)-phenyl]-carbamic acid ethyl ester (AA29504) is a positive allosteric modulator (PAM) of γ-aminobutyric acidA receptors (GABAA Rs), and the modulator has been used in ex vivo/in vivo studies to probe the physiological roles of native δ-containing GABAA Rs. In this study, the functional properties and mode of action of AA29504 were investigated at human GABAA Rs expressed in Xenopus oocytes by two-electrode voltage clamp electrophysiology. AA29504 was found to be an allosteric GABAA R agonist displaying low intrinsic activities at 3-30 μM...
February 15, 2018: Biochemical Pharmacology
https://www.readbyqxmd.com/read/29453293/protein-phosphorylation-maintains-the-normal-function-of-cloned-human-ca-v-2-3-channels
#4
Felix Neumaier, Serdar Alpdogan, Jürgen Hescheler, Toni Schneider
R-type currents mediated by native and recombinant Ca v 2.3 voltage-gated Ca 2+ channels (VGCCs) exhibit facilitation (run-up) and subsequent decline (run-down) in whole-cell patch-clamp recordings. A better understanding of the two processes could provide insight into constitutive modulation of the channels in intact cells, but low expression levels and the need for pharmacological isolation have prevented investigations in native systems. Here, to circumvent these limitations, we use conventional and perforated-patch-clamp recordings in a recombinant expression system, which allows us to study the effects of cell dialysis in a reproducible manner...
February 16, 2018: Journal of General Physiology
https://www.readbyqxmd.com/read/29453030/effects-of-triphenyltin-on-glycinergic-transmission-on-rat-spinal-neurons
#5
Kazuki Noma, Hironari Akaike, Yuki Kurauchi, Hiroshi Katsuki, Yasuo Oyama, Norio Akaike
Glycine is a fast inhibitory transmitter like γ-aminobutyric acid in the mammalian spinal cord and brainstem, and it is involved in motor reflex, nociception, and neuronal development. Triphenyltin (TPT) is an organometallic compound causing environmental hazard to many wild creatures. Our previous findings show that TPT ultimately induces a drain and/or exhaustion of glutamate in excitatory presynaptic nerve terminals, resulted in blockage of neurotransmission as well as methylmercury. Therefore, we have investigated the neurotoxic mechanism how TPT modulates inhibitory glycinergic transmission in the synaptic bouton preparation of rat isolated spinal neurons using a patch clamp technique...
February 13, 2018: Environmental Research
https://www.readbyqxmd.com/read/29452158/protein-kinase-c-epsilon-mediates-the-inhibition-of-angiotensin-ii-on-the-slowly-activating-delayed-rectifier-potassium-current-through-channel-phosphorylation
#6
Xiangbo Gou, Wenying Wang, Sihao Zou, Yajuan Qi, Yanfang Xu
The slowly activating delayed rectifier K + current (I Ks ) is one of the main repolarizing currents in the human heart. Evidence has shown that angiotensin II (Ang II) regulates I Ks through the protein kinase C (PKC) pathway, but the related results are controversial. This study was designed to identify PKC isoenzymes involved in the regulation of I Ks by Ang II and the underlying molecular mechanism. The whole-cell patch-clamp technique was used to record I Ks in isolated guinea pig ventricular cardiomyocytes and in human embryonic kidney (HEK) 293 cells co-transfected with human KCNQ1/KCNE1 genes and Ang II type 1 receptor genes...
February 13, 2018: Journal of Molecular and Cellular Cardiology
https://www.readbyqxmd.com/read/29449639/a-herg-mutation-e1039x-produced-a-synergistic-lesion-on-i-ks-together-with-kcnq1-r174c-mutation-in-a-lqts-family-with-three-compound-mutations
#7
Jie Wu, Yuka Mizusawa, Seiko Ohno, Wei-Guang Ding, Takashi Higaki, Qi Wang, Hirohiko Kohjitani, Takeru Makiyama, Hideki Itoh, Futoshi Toyoda, Andrew F James, Jules C Hancox, Hiroshi Matsuura, Minoru Horie
Congenital long QT syndrome (LQTS) caused by compound mutations is usually associated with more severe clinical phenotypes. We identified a LQTS family harboring three compound mutations in different genes (KCNQ1-R174C, hERG-E1039X and SCN5A-E428K). KCNQ1-R174C, hERG-E1039X and SCN5A-E428K mutations and/or relevant wild-type (WT) cDNAs were respectively expressed in mammalian cells. I Ks -like, I Kr -like, I Na -like currents and the functional interaction between KCNQ1-R174C and hERG-E1039X channels were studied using patch-clamp and immunocytochemistry techniques...
February 15, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29449585/electrical-coupling-between-a17-cells-enhances-reciprocal-inhibitory-feedback-to-rod-bipolar-cells
#8
Claudio Elgueta, Felix Leroy, Alex H Vielma, Oliver Schmachtenberg, Adrian G Palacios
A17 amacrine cells are an important part of the scotopic pathway. Their synaptic varicosities receive glutamatergic inputs from rod bipolar cells (RBC) and release GABA onto the same RBC terminal, forming a reciprocal feedback that shapes RBC depolarization. Here, using patch-clamp recordings, we characterized electrical coupling between A17 cells of the rat retina and report the presence of strongly interconnected and non-coupled A17 cells. In coupled A17 cells, evoked currents preferentially flow out of the cell through GJs and cross-synchronization of presynaptic signals in a pair of A17 cells is correlated to their coupling degree...
February 15, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29447952/insulin-enhances-gaba-a-receptor-mediated-inhibitory-currents-in-rat-central-amygdala-neurons
#9
Sergiy V Korol, Atieh Tafreshiha, Amol K Bhandage, Bryndis Birnir, Zhe Jin
Insulin, a pancreatic hormone, can access the central nervous system, activate insulin receptors distributed in selective brain regions and affect various cellular functions such as neurotransmission. We have previously shown that physiologically relevant concentration of insulin potentiates the GABA A receptor-mediated tonic inhibition and reduces excitability of rat hippocampal CA1 neurons. The central nucleus of the amygdala (CeA) comprises heterogeneous neuronal populations that can respond to hormonal stimulus...
February 12, 2018: Neuroscience Letters
https://www.readbyqxmd.com/read/29447844/angiotensin-ii-facilitates-gabaergic-neurotransmission-at-postsynaptic-sites-in-rat-amygdala-neurons
#10
Bo Hu, Hu Qiao, Tian Cao, Bo Sun, Xiao Luo, Ru Jia, Yuanyuan Fan, Nan Wang, Yi Lu, Jianqun Yan
The central nucleus of the amygdala (CeA) is critical in the regulation of sodium appetite. Angiotensin II (Ang II) is important in the generation of sodium appetite and may function as a neurotransmitter or modulator to affect the synaptic transmission and the excitability of neurons. However, the role of Ang II in the CeA remains unclear. In this study, we determined the effects of Ang II on the excitatory and inhibitory synaptic inputs to the CeA neurons in brain slices with whole-cell patch-clamp recordings...
February 12, 2018: Neuropharmacology
https://www.readbyqxmd.com/read/29446159/arginine-vasopressin-differentially-modulates-gabaergic-synaptic-transmission-onto-temperature-sensitive-and-insensitive-neurons-in-the-rat-preoptic-area
#11
Yu Tang, Yan-Ni Sun, Run Xu, Xiao Huang, Shuang Gu, Cheng-Cheng Hong, Mi-Jia Liu, Heng Jiang, Yong-Lu Yang, Jing Shi
The preoptic area (POA) of the hypothalamus, containing temperature-sensitive and -insensitive neurons, plays a key role in specific thermoregulatory responses. Although arginine vasopressin (AVP) has been shown to induce hypothermia by increasing the firing activities of warm-sensitive neurons and decreasing those of cold-sensitive and temperature-insensitive neurons, the effects of AVP on POA GABAergic transmission remain unknown. Herein, inhibitory postsynaptic currents (IPSCs) of temperature-sensitive and temperature-insensitive neurons in POA slices were recorded using whole-cell patch clamp...
February 15, 2018: European Journal of Neuroscience
https://www.readbyqxmd.com/read/29442545/novel-compound-heterozygous-clcnkb-gene-mutations-c-1755a-g-c-848_850deltct-cause-classic-bartter-syndrome
#12
Chunli Wang, Ying Chen, Bixia Zheng, Mengshu Zhu, Jia Fan, Juejin Wang, Zhanjun Jia, Songming Huang, Aihua Zhang
Inactivated variants in CLCNKB gene encoding the basolateral chloride channel ClC-Kb cause classic Bartter syndrome characterized by hypokalemic metabolic alkalosis and hyperreninemic hyperaldosteronism. Here we identified two cBS siblings presenting hypokalemia in a Chinese family due to novel compound heterozygous CLCNKB mutations (c.848_850delTCT/c.1755A>G). Compound heterozygosity was confirmed by amplifying and sequencing the patient's genomic DNA. The synonymous mutation c.1755A>G (Thr585Thr) was located at +2bp from the 5' splice donor site in exon 15, further transcript analysis demonstrated that this single nucleotide mutation causes exclusion of exon 15 in the cDNA from the proband and his mother...
February 14, 2018: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/29440926/local-anesthetics-for-brain-tumor-resection-current-perspectives
#13
REVIEW
Jan-Willem Potters, Markus Klimek
This review summarizes the added value of local anesthetics in patients undergoing craniotomy for brain tumor resection, which is a procedure that is carried out frequently in neurosurgical practice. The procedure can be carried out under general anesthesia, sedation with local anesthesia or under local anesthesia only. Literature shows a large variation in the postoperative pain intensity ranging from no postoperative analgesia requirement in two-thirds of the patients up to a rate of 96% of the patients suffering from severe postoperative pain...
2018: Local and Regional Anesthesia
https://www.readbyqxmd.com/read/29439248/transient-receptor-potential-vanilloid-4-activation-induced-increase-in-glycine-activated-current-in-mouse-hippocampal-pyramidal-neurons
#14
Mengwen Qi, Chunfeng Wu, Zhouqing Wang, Li Zhou, Chen Men, Yimei Du, Songming Huang, Lei Chen, Ling Chen
BACKGROUND/AIMS: Glycine plays an important role in regulating hippocampal inhibitory/ excitatory neurotransmission through activating glycine receptors (GlyRs) and acting as a co-agonist of N-methyl-d-aspartate-type glutamate receptors. Activation of transient receptor potential vanilloid 4 (TRPV4) is reported to inhibit hippocampal A-type γ-aminobutyric acid receptor, a ligand-gated chloride ion channel. GlyRs are also ligand-gated chloride ion channels and this paper aimed to explore whether activation of TRPV4 could modulate GlyRs...
February 7, 2018: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/29438798/short-term-fasting-decreases-excitatory-synaptic-inputs-to-ventromedial-tuberoinfundibular-dopaminergic-neurons-and-attenuates-their-activity-in-male-mice
#15
Takafumi Kubota, Atsushi Fukushima, Hiroko Hagiwara, Yoshinori Kamiya, Miyako Furuta, Tomoyuki Miyazaki, Hitomi Fujioka, Sei-Etsu Fujiwara, Toshiya Funabashi, Tatsuo Akema
Tuberoinfundibular dopaminergic (TIDA) neurons in the arcuate nucleus (ARC) of the hypothalamus play a role in inhibiting prolactin (PRL) secretion from the anterior pituitary. PRL is involved in a variety of behaviors, including feeding. Consequently, we hypothesized that fasting might reduce the activity of TIDA neurons, which might alter PRL secretion. However, direct examinations of TIDA neuron activity are difficult. Recently, transgenic mice were generated that expressed green fluorescent protein (GFP) under the control of the rat tyrosine hydroxylase gene...
February 10, 2018: Neuroscience Letters
https://www.readbyqxmd.com/read/29437381/optimizing-nanoelectrode-arrays-for-scalable-intracellular-electrophysiology
#16
Jeffrey Abbott, Tianyang Ye, Donhee Ham, Hongkun Park
Electrode technology for electrophysiology has a long history of innovation, with some decisive steps including the development of the voltage-clamp measurement technique by Hodgkin and Huxley in the 1940s and the invention of the patch clamp electrode by Neher and Sakmann in the 1970s. The high-precision intracellular recording enabled by the patch clamp electrode has since been a gold standard in studying the fundamental cellular processes underlying the electrical activities of neurons and other excitable cells...
February 13, 2018: Accounts of Chemical Research
https://www.readbyqxmd.com/read/29434817/%C3%AE-opioid-receptor-inhibition-prevents-remifentanil-induced-post-operative-hyperalgesia-via-regulating-glur1-trafficking-and-ampa-receptor-function
#17
Aifen Liu, Xiaopeng Wang, Hui Wang, Guoyi Lv, Yize Li, Hongmei Li
The interaction of remifentanil with glutamate systems has an important role in remifentanil-induced thermal and mechanical hyperalgesia. A previous study by our group suggested that the trafficking and function of glutamate receptor 1 (GluR1) subunits contributes to remifentanil-induced hyperalgesia by regulating the phosphorylation of GluR1 in dorsal horn neurons. The present study demonstrated that δ opioid receptor (DOR) inhibition prevented thermal and mechanical hyperalgesia, which was induced by remifentanil infusion via attenuating GluR1 subunit trafficking and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) function in dorsal horn neurons...
February 2018: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/29422839/exercise-induced-fatigue-impairs-bidirectional-corticostriatal-synaptic-plasticity
#18
Jing Ma, Huimin Chen, Xiaoli Liu, Lingtao Zhang, Decai Qiao
Exercise-induced fatigue (EF) is a ubiquitous phenomenon in sports competition and training. It can impair athletes' motor skill execution and cognition. Corticostriatal synaptic plasticity is considered to be the cellular mechanism of movement control and motor learning. However, the effect of EF on corticostriatal synaptic plasticity remains elusive. In the present study, using field excitatory postsynaptic potential recording, we found that the corticostriatal long-term potentiation (LTP) and long-term depression (LTD) were both impaired in EF mice...
2018: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/29421809/a-potassium-selective-current-affected-by-micromolar-concentrations-of-anion-transport-inhibitors
#19
Roberta Costa, Davide Antonio Civello, Emanuele Bernardinelli, Simone Vanoni, Michaela Zopf, Giada Scantamburlo, Charity Nofziger, Wolfgang Patsch, Markus Paulmichl, Silvia Dossena
BACKGROUND/AIMS: In the human genome, more than 400 genes encode ion channels, which are ubiquitously expressed and often coexist and participate in almost all physiological processes. Therefore, ion channel blockers represent fundamental tools in discriminating the contribution of individual channel types to a physiological phenomenon. However, unspecific effects of these compounds may represent a confounding factor. Three commonly used chloride channel inhibitors, i.e. 4,4'-diisothiocyano-2,2'-stilbene-disulfonic acid (DIDS), 5-nitro-2-[(3-phenylpropyl) amino]benzoic acid (NPPB) and the anti-inflammatory drug niflumic acid were tested to identify the lowest concentration effective on Cl- channels and ineffective on K+ channels...
February 2, 2018: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/29421412/right-subclavian-artery-aneurysms-with-fibromuscular-dysplasia
#20
Daisuke Kaneyuki, Hideki Ueda, Goro Matsumiya
Subclavian artery aneurysms are rare and even more uncommon in patients with fibromuscular dysplasia. A 20-year-old man with a past medical history of moyamoya disease, presented with an abnormal mass shadow in the apex of the right lung on chest x-ray. Based on computed tomography imaging, a diagnosis of right subclavian artery aneurysm was established and an excision of the aneurysm was performed. Since the left vertebral artery is dominant, the proximal and distal right subclavian artery and right vertebral artery were clamped...
February 5, 2018: Annals of Vascular Surgery
keyword
keyword
14648
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"