A component of excitation-contraction coupling triggered in the absence of the T671-L690 and L720-Q765 regions of the II-III loop of the dihydropyridine receptor alpha(1s) pore subunit.
AuthorsAhern CA, Bhattacharya D, Mortenson L, Coronado R
JournalBiophys J
PubMed ID11720993
'We conducted a deletion analysis of two regions identified in the II-III loop of alpha(1S), residues 671-690, which were shown to bind to ryanodine receptor type 1 (RyR1) and stimulate RyR1 channels in vitro, and residues 720-765 or the narrower 724-743 region, which confer excitation-contraction (EC) coupling function to chimeric ... More
Initiation and propagation of regenerative Ca(2+)-dependent potentials in dendrites of layer 5 pyramidal neurons.
AuthorsOakley JC, Schwindt PC, Crill WE
JournalJ Neurophysiol
PubMed ID11431528
'The initiation and propagation of dendritic Ca(2+)-dependent regenerative potentials (CDRPs) were investigated by imaging the Ca(2+)-sensitive dye Fluo-4 during whole cell recording from the soma of layer 5 pyramidal neurons visualized in a slice preparation of rat neocortex by the use of infrared-differential interference contrast microscopy. CDRPs were evoked by ... More
Integration of multianalyte sensing functions on a capillary-assembled microchip: simultaneous determination of ion concentrations and enzymatic activities by a "drop-and-sip" technique.
AuthorsHenares TG, Takaishi M, Yoshida N, Terabe S, Mizutani F, Sekizawa R, Hisamoto H
JournalAnal Chem
PubMed ID17263315
'A general and simple implementation of simultaneous multiparametric sensing in a single microchip is presented by using a capillary-assembled microchip (CAs-CHIP) integrated with the plural different reagent-release capillaries (RRCs), acting as various biochemical sensors. A novel "drop-and-sip" technique of fluid handling is performed with a microliter droplet of a model ... More
NAADP controls cross-talk between distinct Ca2+ stores in the heart.
AuthorsMacgregor A, Yamasaki M, Rakovic S, Sanders L, Parkesh R, Churchill GC, Galione A, Terrar DA
JournalJ Biol Chem
PubMed ID17387177
'In cardiac muscle the sarcoplasmic reticulum (SR) plays a key role in the control of contraction, releasing Ca(2+) in response to Ca(2+) influx across the sarcolemma via voltage-gated Ca(2+) channels. Here we report evidence for an additional distinct Ca(2+) store and for actions of nicotinic acid adenine dinucleotide phosphate (NAADP) ... More
Long-term potentiation of exogenous glutamate responses at single dendritic spines.
AuthorsBagal AA, Kao JP, Tang CM, Thompson SM
JournalProc Natl Acad Sci U S A
PubMed ID16186507
'Long-term increases in the strength of excitatory transmission at Schaffer collateral-CA1 cell synapses of the hippocampus require the insertion of new alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors (AMPARs) into the synapse, but the kinetics of this process are not well established. Using microphotolysis of caged glutamate to activate receptors at single dendritic spines in ... More
P2X7 receptor inhibition improves recovery after spinal cord injury.
AuthorsWang X, Arcuino G, Takano T, Lin J, Peng WG, Wan P, Li P, Xu Q, Liu QS, Goldman SA, Nedergaard M
JournalNat Med
PubMed ID15258577
'Secondary injury exacerbates the extent of spinal cord insults, yet the mechanistic basis of this phenomenon has largely been unexplored. Here we report that broad regions of the peritraumatic zone are characterized by a sustained process of pathologic, high ATP release. Spinal cord neurons expressed P2X7 purine receptors (P2X7R), and ... More
SparkMaster: automated calcium spark analysis with ImageJ.
AuthorsPicht E, Zima AV, Blatter LA, Bers DM,
JournalAm J Physiol Cell Physiol
PubMed ID17376815
'Ca sparks are elementary Ca-release events from intracellular Ca stores that are observed in virtually all types of muscle. Typically, Ca sparks are measured in the line-scan mode with confocal laser-scanning microscopes, yielding two-dimensional images (distance vs. time). The manual analysis of these images is time consuming and prone to ... More
Activity-dependent long-term potentiation of intrinsic excitability in hippocampal CA1 pyramidal neurons.
AuthorsXu J, Kang N, Jiang L, Nedergaard M, Kang J
JournalJ Neurosci
PubMed ID15716411
'The efficiency of neural circuits is enhanced not only by increasing synaptic strength but also by increasing intrinsic excitability. In contrast to the detailed analysis of long-term potentiation (LTP), less attention has been given to activity-dependent changes in the intrinsic neuronal excitability. By stimulating hippocampal CA1 pyramidal neurons with synaptic ... More
Analysis of calcium channels in single spines using optical fluctuation analysis.
AuthorsSabatini BL, Svoboda K
JournalNature
PubMed ID11117746
'Most synapses form on small, specialized postsynaptic structures known as dendritic spines. The influx of Ca2+ ions into such spines--through synaptic receptors and voltage-sensitive Ca2+ channels (VSCCs)--triggers diverse processes that underlie synaptic plasticity. Using two-photon laser scanning microscopy, we imaged action-potential-induced transient changes in Ca2+ concentration in spines and dendrites ... More
Nonlinear [Ca2+] signaling in dendrites and spines caused by activity-dependent depression of Ca2+ extrusion.
AuthorsScheuss V, Yasuda R, Sobczyk A, Svoboda K
JournalJ Neurosci
PubMed ID16885232
'Spine Ca2+ triggers the induction of synaptic plasticity and other adaptive neuronal responses. The amplitude and time course of Ca2+ signals specify the activation of the signaling pathways that trigger different forms of plasticity such as long-term potentiation and depression. The shapes of Ca2+ signals are determined by the dynamics ... More
In vivo two-photon laser-scanning microscopy of Ca2+ dynamics in visual motion-sensitive neurons.
AuthorsKalb J, Nielsen T, Fricke M, Egelhaaf M, Kurtz R
JournalBiochem Biophys Res Commun
PubMed ID15020223
'We applied two-photon laser-scanning microscopy (TPLSM) to motion-sensitive visual interneurons of the fly to study Ca(2+) dynamics in vivo at a higher spatial and temporal resolution than possible with conventional fluorescence microscopy. Based on a custom-built two-photon microscope, we performed line scans to measure changes in presynaptic Ca(2+) concentrations elicited ... More
T-type Ca(2+) channels mediate neurotransmitter release in retinal bipolar cells.
AuthorsPan ZH, Hu HJ, Perring P, Andrade R
JournalNeuron
PubMed ID11604141
'Transmitter release in neurons is thought to be mediated exclusively by high-voltage-activated (HVA) Ca(2+) channels. However, we now report that, in retinal bipolar cells, low-voltage-activated (LVA) Ca(2+) channels also mediate neurotransmitter release. Bipolar cells are specialized neurons that release neurotransmitter in response to graded depolarizations. Here we show that these ... More
Beta 1-subunits are required for regulation of coupling between Ca2+ transients and Ca2+-activated K+ (BK) channels by protein kinase C.
AuthorsHagen BM, Bayguinov O, Sanders KM
JournalAm J Physiol Cell Physiol
PubMed ID12867357
'Colonic myocytes have spontaneous, localized, Ins (1,4,5) trisphosphate (IP3) receptor-dependent Ca2+ transients that couple to the activation of Ca2+-dependent K+ channels and spontaneous transient outward currents (STOCs). We previously reported that the coupling strength between spontaneous Ca2+ transients and large conductance Ca2+ activated K+ (BK) channels is regulated by Ca2+ ... More
'Our understanding of the underlying mechanisms of Ca2+ signaling as well as our appreciation for its ubiquitous role in cellular processes has been rapidly advanced, in large part, due to the development of fluorescent Ca2+ indicators. In this chapter, we discuss some of the most common chemical Ca2+ indicators that ... More
Extracellular Ca2+ depletion contributes to fast activity-dependent modulation of synaptic transmission in the brain.
AuthorsRusakov DA, Fine A
JournalNeuron
PubMed ID12546823
'Synaptic activation is associated with rapid changes in intracellular Ca(2+), while the extracellular Ca(2+) level is generally assumed to be constant. Here, using a novel optical method to measure changes in extracellular Ca(2+) at high spatial and temporal resolution, we find that brief trains of synaptic transmission in hippocampal area ... More
Modulation of presynaptic Ca2+ entry by AMPA receptors at individual GABAergic synapses in the cerebellum.
AuthorsRusakov DA, Saitow F, Lehre KP, Konishi S
JournalJ Neurosci
PubMed ID15901774
'Cerebellar Purkinje cells (PCs) receive GABAergic input that undergoes powerful retrograde modulation by presynaptic cannabinoid and glutamate receptors. Here we examine a distinct modulatory mechanism at these synapses, which does not require postsynaptic depolarization and acts via presynaptic AMPA receptors. We find that this mechanism operates mainly in the somatic ... More
Novel fluo-4 analogs for fluorescent calcium measurements.
AuthorsMartin VV, Beierlein M, Morgan JL, Rothe A, Gee KR
JournalCell Calcium
PubMed ID15488600
We report new fluorescent calcium indicators based on fluo-4. Attachment of a carboxamide or methylenecarboxamide moiety to the BAPTA chelator portion of fluo-4 allowed for the attachment of dextrans, protein-reactive moieties, and biotin. In particular, a high affinity fluo-4 dextran conjugate was prepared and shown to be functional in brain ... More
Electrophysiology in the age of light.
AuthorsScanziani M, Häusser M,
JournalNature
PubMed ID19829373
Electrophysiology, the 'gold standard' for investigating neuronal signalling, is being challenged by a new generation of optical probes. Together with new forms of microscopy, these probes allow us to measure and control neuronal signals with spatial resolution and genetic specificity that already greatly surpass those of electrophysiology. We predict that ... More
The life cycle of Ca(2+) ions in dendritic spines.
AuthorsSabatini BL, Oertner TG, Svoboda K
JournalNeuron
PubMed ID11832230
Spine Ca(2+) is critical for the induction of synaptic plasticity, but the factors that control Ca(2+) handling in dendritic spines under physiological conditions are largely unknown. We studied [Ca(2+)] signaling in dendritic spines of CA1 pyramidal neurons and find that spines are specialized structures with low endogenous Ca(2+) buffer capacity ... More
Methods for studying store-operated calcium entry.
AuthorsBird GS, DeHaven WI, Smyth JT, Putney JW,
JournalMethods
PubMed ID18929662
Activation of surface membrane receptors coupled to phospholipase C results in the generation of cytoplasmic Ca2+ signals comprised of both intracellular Ca2+ release, and enhanced entry of Ca2+ across the plasma membrane. A primary mechanism for this Ca2+ entry process is attributed to store-operated Ca2+ entry, a process that is ... More
Dye loading with patch pipettes.
AuthorsEilers J, Konnerth A,
JournalCSH Protoc
PubMed ID20147143
This protocol describes the loading of individual cells with fluorescent probes via patch pipettes. The patch-clamp methodology has been successfully used for single-cell dye labeling in cultured neurons, brain slices, and in vivo preparations. A broad range of dyes can be used with this loading technique. Markers for morphological reconstruction ... More
The number of glutamate receptors opened by synaptic stimulation in single hippocampal spines.
AuthorsNimchinsky EA, Yasuda R, Oertner TG, Svoboda K
JournalJ Neurosci
PubMed ID14985448
The number of receptors opening after glutamate release is critical for understanding the sources of noise and the dynamic range of synaptic transmission. We imaged [Ca2+] transients mediated by synaptically activated NMDA receptors (NMDA-Rs) in individual spines in rat brain slices. We show that Ca2+ influx through single NMDA-Rs can ... More
GABAergic excitation promotes neuronal differentiation in adult hippocampal progenitor cells.
AuthorsTozuka Y, Fukuda S, Namba T, Seki T, Hisatsune T
JournalNeuron
PubMed ID16157276
Hippocampal activity influences neurogenesis in the adult dentate gyrus; however, little is known about the involvement of the hippocampal circuitry in this process. In the subgranular zone of the adult dentate gyrus, neurogenesis involves a series of differentiation steps from radial glia-like stem/progenitor (type-1) cells, to transiently amplifying neuronal progenitor ... More
Selective stimulation of astrocyte calcium in situ does not affect neuronal excitatory synaptic activity.
Astrocytes are considered the third component of the synapse, responding to neurotransmitter release from synaptic terminals and releasing gliotransmitters--including glutamate--in a Ca(2+)-dependent manner to affect neuronal synaptic activity. Many studies reporting astrocyte-driven neuronal activity have evoked astrocyte Ca(2+) increases by application of endogenous ligands that directly activate neuronal receptors, making ... More
Localized calcium signals along the cleavage furrow of the Xenopus egg are not involved in cytokinesis.
AuthorsNoguchi T, Mabuchi I
JournalMol Biol Cell
PubMed ID11950937
It has been proposed that a localized calcium (Ca) signal at the growing end of the cleavage furrow triggers cleavage furrow formation in large eggs. We have examined the possible role of a Ca signal in cleavage furrow formation in the Xenopus laevis egg during the first cleavage. We were ... More
Dual effects of cyclic ADP-ribose on sarcoplasmic reticulum Ca2+ release and storage in cardiac myocytes isolated from guinea-pig and rat ventricle.
AuthorsMacgregor AT, Rakovic S, Galione A, Terrar DA
JournalCell Calcium
PubMed ID17156839
The actions of cyclic ADP-ribose (cADPR), a regulator of Ca2+-induced Ca2+ release (CICR), were investigated on Ca2+ release and sarcoplasmic reticulum (SR) Ca2+ loading in cardiac myocytes at physiological temperature. In guinea-pig ventricular cells, cADPR, applied via patch pipette or from photorelease of its caged derivative, increased contraction amplitude and ... More
Role of mitochondria in kainate-induced fast Ca2+ transients in cultured spinal motor neurons.
AuthorsGrosskreutz J, Haastert K, Dewil M, Van Damme P, Callewaert G, Robberecht W, Dengler R, Van Den Bosch L
JournalCell Calcium
PubMed ID17241659
Motor neuron death in amyotrophic lateral sclerosis (ALS) has been linked to selective vulnerability towards AMPA receptor-mediated excitotoxicity. We investigated intracellular mechanisms leading to impairment of motor neuron Ca2+ homeostasis with near physiological AMPA receptor activation. Using fast solution exchange on patch-clamped cultured neurons, kainate (KA) was applied for 2s. ... More
Chemical and physiological characterization of fluo-4 Ca(2+)-indicator dyes.
AuthorsGee KR, Brown KA, Chen WN, Bishop-Stewart J, Gray D, Johnson I
JournalCell Calcium
PubMed ID10756976
We have developed fluo-4, a new fluorescent dye for quantifying cellular Ca2+ concentrations in the 100 nM to 1 microM range. Fluo-4 is similar in structure and spectral properties to the widely used fluorescent Ca(2+)-indicator dye, fluo-3, but it has certain advantages over fluo-3. Due to its greater absorption near ... More
Local uncaging of caged Ca(2+) reveals distribution of Ca(2+)-activated Cl(-) channels in pancreatic acinar cells.
AuthorsPark MK, Lomax RB, Tepikin AV, Petersen OH
JournalProc Natl Acad Sci U S A
PubMed ID11535807
In exocrine acinar cells, Ca(2+)-activated Cl(-) channels in the apical membrane are essential for fluid secretion, but it is unclear whether such channels are important for Cl(-) uptake at the base. Whole-cell current recording, combined with local uncaging of caged Ca(2+), was used to reveal the Cl(-) channel distribution in ... More
Dynamic regulation of spine-dendrite coupling in cultured hippocampal neurons.
AuthorsKorkotian E, Holcman D, Segal M
JournalEur J Neurosci
PubMed ID15548208
We investigated the role of dendritic spine morphology in spine-dendrite calcium communication using novel experimental and theoretical approaches. A transient rise in [Ca2+]i was produced in individual spine heads of Fluo-4-loaded cultured hippocampal neurons by flash photolysis of caged calcium. Following flash photolysis in the spine head, a delayed [Ca2+]i ... More
Ca(2+)-induced Ca(2+) release in sensory neurons: low gain amplification confers intrinsic stability.
AuthorsOuyang K, Wu C, Cheng H
JournalJ Biol Chem
PubMed ID15749692
Ca(2+)-induced Ca(2+) release (CICR) is a ubiquitous mechanism by which Ca(2+) release from the endoplasmic reticulum amplifies the trigger Ca(2+) entry and generates propagating Ca(2+) waves. To elucidate the mechanisms that control this positive feedback, we investigated the spatial and temporal kinetics and measured the gain function of CICR in ... More
Cold-induced calcium elevation triggers DNA fragmentation in immature pig oocytes.
AuthorsMattioli M, Barboni B, Gioia L, Loi P, Luisa G
JournalMol Reprod Dev
PubMed ID12784251
Fluo-4 loaded immature oocytes were cooled from 30 degrees C to various lower temperatures between 20 and 10 degrees C and changes in intracellular calcium (Ca(2+)) levels were measured. Pig oocytes cooled to 14 degrees C exhibited a clear biphasic Ca(2+) rise. Lower temperatures produced similar responses, while higher temperatures ... More
A comparison of fluorescent Ca2+ indicator properties and their use in measuring elementary and global Ca2+ signals.
AuthorsThomas D, Tovey SC, Collins TJ, Bootman MD, Berridge MJ, Lipp P
JournalCell Calcium
PubMed ID11032777
Quantifying the magnitude of Ca2+ signals from changes in the emission of fluorescent indicators relies on assumptions about the indicator behaviour in situ. Factors such as osmolarity, pH, ionic strength and protein environment can affect indicator properties making it advantageous to calibrate indicators within the required cellular or subcellular environment. ... More
Application of multiline two-photon microscopy to functional in vivo imaging.
AuthorsKurtz R, Fricke M, Kalb J, Tinnefeld P, Sauer M
JournalJ Neurosci Methods
PubMed ID16442636
High spatial resolution and low risks of photodamage make two-photon laser-scanning microscopy (TPLSM) the method of choice for biological imaging. However, the study of functional dynamics such as neuronal calcium regulation often also requires a high temporal resolution. Hitherto, acquisition speed is usually increased by line scanning, which restricts spatial ... More
Timing of Ca(2+) release from intracellular stores and the electrical response of Limulus ventral photoreceptors to dim flashes.
AuthorsPayne R, Demas J
JournalJ Gen Physiol
PubMed ID10828247
Light-induced release of Ca(2+) from stores in Limulus ventral photoreceptors was studied using confocal fluorescence microscopy and the Ca(2+) indicator dyes, Oregon green-5N and fluo-4. Fluorescence was collected from a spot within 4 microm of the microvillar membrane. A dual-flash protocol was used to reconstruct transient elevations of intracellular free ... More
Cytosolic phospholipase A(2) alpha mediates electrophysiologic responses of hippocampal pyramidal neurons to neurotoxic NMDA treatment.
AuthorsShen Y, Kishimoto K, Linden DJ, Sapirstein A
JournalProc Natl Acad Sci U S A
PubMed ID17389392
The arachidonic acid-generating enzyme cytosolic phospholipase A(2) alpha (cPLA(2)alpha) has been implicated in the progression of excitotoxic neuronal injury. However, the mechanisms of cPLA(2)alpha toxicity have yet to be determined. Here, we used a model system exposing mouse hippocampal slices to NMDA as an excitotoxic injury, in combination with simultaneous ... More
Measurement of cytoplasmic calcium concentration in the rods of wild-type and transducin knock-out mice.
A 10 microm spot of argon laser light was focused onto the outer segments of intact mouse rods loaded with fluo-3, fluo-4 or fluo-5F, to estimate dark, resting free Ca(2+) concentration ([Ca(2+)](i)) and changes in [Ca(2+)](i) upon illumination. Dye concentration was adjusted to preserve the normal physiology of the rod, ... More
Direct visualization of sarcoplasmic reticulum regions discharging Ca(2+)sparks in vascular myocytes.
AuthorsGordienko DV, Greenwood IA, Bolton TB
JournalCell Calcium
PubMed ID11133352
Localized Ca(2+)-release events, Ca(2+)sparks, have been suggested to be the 'elementary building blocks' of the calcium signalling system in all types of muscles. In striated muscles these occur at regular intervals along the fibre corresponding to the sarcomeric structures which do not exist in smooth muscle. We showed previously that ... More
The gut microbiota metabolite urolithin A inhibits NF-κB activation in LPS stimulated BMDMs.
Authors
JournalSci Rep
PubMed ID33782464
Sculpting and fusing biomimetic vesicle networks using optical tweezers.
Authors
JournalNat Commun
PubMed ID29760422
Phasic Store-Operated Ca2+ Entry During Excitation-Contraction Coupling in Skeletal Muscle Fibers From Exercised Mice.
Authors
JournalFront Physiol
PubMed ID33262706
Carbon Nanotube Porins in Amphiphilic Block Copolymers as Fully Synthetic Mimics of Biological Membranes.
Authors
JournalAdv Mater
PubMed ID30368926
Cardiac ryanodine receptor distribution is dynamic and changed by auxiliary proteins and post-translational modification.
Authors
JournalElife
PubMed ID31916935
Biophysical classification of a CACNA1D de novo mutation as a high-risk mutation for a severe neurodevelopmental disorder.
Authors
JournalMol Autism
PubMed ID31921405
TRPC3 and NALCN channels drive pacemaking in substantia nigra dopaminergic neurons.
Authors
JournalElife
PubMed ID34409942
Release probability increases towards distal dendrites boosting high-frequency signal transfer in the rodent hippocampus.
Authors
JournalElife
PubMed ID33438578
LTP Induction Boosts Glutamate Spillover by Driving Withdrawal of Perisynaptic Astroglia.
Authors
JournalNeuron
PubMed ID32976770
Simultaneous recording of multiple cellular signaling events by frequency- and spectrally-tuned multiplexing of fluorescent probes.