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Li J, Zhai J, Wang Y, Yang W, Xie X. Dual functional luminescent nanoprobes for monitoring oxygen and chloride concentration changes in cells. Chem Commun (Camb) 2020; 56:14980-14983. [PMID: 33179655 DOI: 10.1039/d0cc06258h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A dual functional nanoprobe Pd-Q+@PDMS was proposed to simultaneously monitor Cl- and O2, leading to the determination of an average Cl- concentration of 85.7 ± 5.5 mM in lysosomes of HeLa cells. Mimicking ischemic conditions, the cells exhibited a luminescence change corresponding to a decreasing subcellular Cl- concentration.
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Affiliation(s)
- Jing Li
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
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2
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Arosio D, Ratto GM. Twenty years of fluorescence imaging of intracellular chloride. Front Cell Neurosci 2014; 8:258. [PMID: 25221475 PMCID: PMC4148895 DOI: 10.3389/fncel.2014.00258] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/12/2014] [Indexed: 11/23/2022] Open
Abstract
Chloride homeostasis has a pivotal role in controlling neuronal excitability in the adult brain and during development. The intracellular concentration of chloride is regulated by the dynamic equilibrium between passive fluxes through membrane conductances and the active transport mediated by importers and exporters. In cortical neurons, chloride fluxes are coupled to network activity by the opening of the ionotropic GABAA receptors that provides a direct link between the activity of interneurons and chloride fluxes. These molecular mechanisms are not evenly distributed and regulated over the neuron surface and this fact can lead to a compartmentalized control of the intracellular concentration of chloride. The inhibitory drive provided by the activity of the GABAA receptors depends on the direction and strength of the associated currents, which are ultimately dictated by the gradient of chloride, the main charge carrier flowing through the GABAA channel. Thus, the intracellular distribution of chloride determines the local strength of ionotropic inhibition and influences the interaction between converging excitation and inhibition. The importance of chloride regulation is also underlined by its involvement in several brain pathologies, including epilepsy and disorders of the autistic spectra. The full comprehension of the physiological meaning of GABAergic activity on neurons requires the measurement of the spatiotemporal dynamics of chloride fluxes across the membrane. Nowadays, there are several available tools for the task, and both synthetic and genetically encoded indicators have been successfully used for chloride imaging. Here, we will review the available sensors analyzing their properties and outlining desirable future developments.
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Affiliation(s)
- Daniele Arosio
- Institute of Biophysics, National Research Council and Bruno Kessler Foundation Trento, Italy ; Centre for Integrative Biology, University of Trento Trento, Italy
| | - Gian Michele Ratto
- Nanoscience Institute, National Research Council of Italy Pisa, Italy ; NEST, Scuola Normale Superiore Pisa, Italy
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Kolbaev SN, Achilles K, Luhmann HJ, Kilb W. Effect of depolarizing GABA(A)-mediated membrane responses on excitability of Cajal-Retzius cells in the immature rat neocortex. J Neurophysiol 2011; 106:2034-44. [PMID: 21775719 DOI: 10.1152/jn.00699.2010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In immature neurons activation of ionotropic GABA receptors induces depolarizing membrane responses due to a high intracellular Cl(-) concentration ([Cl(-)](i)). However, it is difficult to draw conclusions about the functional consequences of subthreshold GABAergic depolarizations, since GABAergic membrane shunting and additional effects on voltage-dependent ion channels or action potential threshold must be considered. To systematically investigate factors that determine the GABAergic effect on neuronal excitability we performed whole cell patch-clamp recordings from Cajal-Retzius cells in immature rat neocortex, using [Cl(-)](i) between 10 and 50 mM. The effect of focal GABA application was quantified by measuring various parameters of GABAergic responses including the shift in minimal threshold current (rheobase). The rheobase shift was correlated with other parameters of the GABAergic responses by multiple linear regression analyses with a set of simple mathematical models. Our experiments demonstrate that focal GABA application induces heterogeneous rheobase shifts in Cajal-Retzius cells that could not be predicted reliably from [Cl(-)](i) or the GABAergic membrane depolarization. Implementation of a linear mathematical model, which takes the GABAergic membrane conductance and the difference between action potential threshold and GABA reversal potential into account, resulted in a close correlation between calculated and experimentally obtained rheobase shifts. Addition of a linear term proportional to the GABAergic membrane depolarization improved the accuracy of correlation. The main advantage of using multiple linear regression with simple models is that direction and strength of GABAergic excitability shifts can be analyzed by using only measured parameters of GABAergic responses and with minimal a priori information about cellular parameters.
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Affiliation(s)
- S N Kolbaev
- Institute of Physiology and Pathophysiology, University Medical Center Mainz, Johannes Gutenberg University, Mainz, Germany
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Galanopoulou AS. GABA(A) receptors in normal development and seizures: friends or foes? Curr Neuropharmacol 2008; 6:1-20. [PMID: 19305785 PMCID: PMC2645547 DOI: 10.2174/157015908783769653] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 05/24/2007] [Accepted: 08/05/2007] [Indexed: 12/26/2022] Open
Abstract
GABA(A) receptors have an age-adapted function in the brain. During early development, they mediate excitatory effects resulting in activation of calcium sensitive signaling processes that are important for the differentiation of the brain. In more mature stages of development and in adults, GABA(A) receptors transmit inhibitory signals. The maturation of GABA(A) signaling follows sex-specific patterns, which appear to also be important for the sexual differentiation of the brain. The inhibitory effects of GABA(A) receptor activation have been widely exploited in the treatment of conditions where neuronal silencing is necessary. For instance, drugs that target GABA(A) receptors are the mainstay of treatment of seizures. Recent evidence suggests however that the physiology and function of GABA(A) receptors changes in the brain of a subject that has epilepsy or status epilepticus.This review will summarize the physiology of and the developmental factors regulating the signaling and function of GABA(A) receptors; how these may change in the brain that has experienced prior seizures; what are the implications for the age and sex specific treatment of seizures and status epilepticus. Finally, the implications of these changes for the treatment of certain forms of medically refractory epilepsies and status epilepticus will be discussed.
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Affiliation(s)
- Aristea S Galanopoulou
- Albert Einstein College of Medicine, Saul R Korey Department of Neurology & Dominick P Purpura, Department of Neuroscience, Bronx NY, USA.
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Adragna NC, Di Fulvio M, Lauf PK. Regulation of K-Cl cotransport: from function to genes. J Membr Biol 2005; 201:109-37. [PMID: 15711773 DOI: 10.1007/s00232-004-0695-6] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Revised: 06/10/2004] [Indexed: 11/27/2022]
Abstract
This review intends to summarize the vast literature on K-Cl cotransport (COT) regulation from a functional and genetic viewpoint. Special attention has been given to the signaling pathways involved in the transporter's regulation found in several tissues and cell types, and more specifically, in vascular smooth muscle cells (VSMCs). The number of publications on K-Cl COT has been steadily increasing since its discovery at the beginning of the 1980s, with red blood cells (RBCs) from different species (human, sheep, dog, rabbit, guinea pig, turkey, duck, frog, rat, mouse, fish, and lamprey) being the most studied model. Other tissues/cell types under study are brain, kidney, epithelia, muscle/smooth muscle, tumor cells, heart, liver, insect cells, endothelial cells, bone, platelets, thymocytes and Leishmania donovani. One of the salient properties of K-Cl-COT is its activation by cell swelling and its participation in the recovery of cell volume, a process known as regulatory volume decrease (RVD). Activation by thiol modification with N-ethylmaleimide (NEM) has spawned investigations on the redox dependence of K-Cl COT, and is used as a positive control for the operation of the system in many tissues and cells. The most accepted model of K-Cl COT regulation proposes protein kinases and phosphatases linked in a chain of phosphorylation/dephosphorylation events. More recent studies include regulatory pathways involving the phosphatidyl inositol/protein kinase C (PKC)-mediated pathway for regulation by lithium (Li) in low-K sheep red blood cells (LK SRBCs), and the nitric oxide (NO)/cGMP/protein kinase G (PKG) pathway as well as the platelet-derived growth factor (PDGF)-mediated mechanism in VSMCs. Studies on VSM transfected cells containing the PKG catalytic domain demonstrated the participation of this enzyme in K-Cl COT regulation. Commonly used vasodilators activate K-Cl COT in a dose-dependent manner through the NO/cGMP/PKG pathway. Interaction between the cotransporter and the cytoskeleton appears to depend on the cellular origin and experimental conditions. Pathophysiologically, K-Cl COT is altered in sickle cell anemia and neuropathies, and it has also been proposed to play a role in blood pressure control. Four closely related human genes code for KCCs (KCC1-4). Although considerable information is accumulating on tissue distribution, function and pathologies associated with the different isoforms, little is known about the genetic regulation of the KCC genes in terms of transcriptional and post-transcriptional regulation. A few reports indicate that the NO/cGMP/PKG signaling pathway regulates KCC1 and KCC3 mRNA expression in VSMCs at the post-transcriptional level. However, the detailed mechanisms of post-transcriptional regulation of KCC genes and of regulation of KCC2 and KCC4 mRNA expression are unknown. The K-Cl COT field is expected to expand further over the next decades, as new isoforms and/or regulatory pathways are discovered and its implication in health and disease is revealed.
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Affiliation(s)
- N C Adragna
- Department of Pharmacology, Wright State University, School of Medicine, Dayton, OH 45435-0002, USA.
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Pond BB, Galeffi F, Ahrens R, Schwartz-Bloom RD. Chloride transport inhibitors influence recovery from oxygen-glucose deprivation-induced cellular injury in adult hippocampus. Neuropharmacology 2004; 47:253-62. [PMID: 15223304 DOI: 10.1016/j.neuropharm.2004.04.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2003] [Revised: 03/24/2004] [Accepted: 04/22/2004] [Indexed: 11/16/2022]
Abstract
Cerebral ischemia in vivo or oxygen-glucose deprivation (OGD) in vitro are characterized by major disturbances in neuronal ionic homeostasis, including significant rises in intracellular Na(+), Ca(2+), and Cl(-) and extracellular K(+). Recently, considerable attention has been focused on the cation-chloride cotransporters Na-K-Cl cotransporter isoform I (NKCC-1) and K-Cl cotransporter isoform II (KCC2), as they may play an important role in the disruption of ion gradients and subsequent ischemic damage. In this study, we examined the ability of cation-chloride transport inhibitors to influence the biochemical (i.e. ATP) and histological recovery of neurons in adult hippocampal slices exposed to OGD. In the hippocampus, 7 min of OGD caused a loss of ATP that recovered partially (approximately 50%) during 3 h of reoxygenation. Furosemide, which inhibits the NKCC-1 and KCC2 cotransporters, and bumetanide, a more specific NKCC-1 inhibitor, enhanced ATP recovery when measured 3 h after OGD. Furosemide and bumetanide also attenuated area CA1 neuronal injury after OGD. However, higher concentrations of these compounds appear to have additional non-specific toxic effects, limiting ATP recovery following OGD and promoting neuronal injury. The KCC2 cotransporter inhibitor DIOA and the Cl(-) ATPase inhibitor ethacrynic acid caused neuronal death even in the absence of OGD and promoted cytochrome c release from isolated mitochondria, indicating non-specific toxicities of these compounds.
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Affiliation(s)
- Brooks B Pond
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Box 3813, Durham, NC 27710, USA
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Slemmer JE, Matsushita S, De Zeeuw CI, Weber JT, Knöpfel T. Glutamate-induced elevations in intracellular chloride concentration in hippocampal cell cultures derived from EYFP-expressing mice. Eur J Neurosci 2004; 19:2915-22. [PMID: 15182298 DOI: 10.1111/j.0953-816x.2004.03422.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The homeostasis of intracellular Cl(-) concentration ([Cl(-)](i)) is critical for neuronal function, including gamma-aminobutyric acid (GABA)ergic synaptic transmission. Here, we investigated activity-dependent changes in [Cl(-)](i) using a transgenetically expressed Cl(-)-sensitive enhanced yellow-fluorescent protein (EYFP) in cultures of mouse hippocampal neurons. Application of glutamate (100 microm for 3 min) in a bath perfusion to cell cultures of various days in vitro (DIV) revealed a decrease in EYFP fluorescence. The EYFP signal increased in amplitude with increasing DIV, reaching a maximal response after 7 DIV. Glutamate application resulted in a slight neuronal acidification. Although EYFP fluorescence is sensitive to pH, EYFP signals were virtually abolished in Cl(-)-free solution, demonstrating that the EYFP signal represented an increase in [Cl(-)](i). Similar to glutamate, a rise in [Cl(-)](i) was also induced by specific ionotropic glutamate receptor agonists and by increasing extracellular [K(+)], indicating that an increase in driving force for Cl(-) suffices to increase [Cl(-)](i). To elucidate the membrane mechanisms mediating the Cl(-) influx, a series of blockers of ion channels and transporters were tested. The glutamate-induced increase in [Cl(-)](i) was resistant to furosemide, bumetanide and 4,4'-diisothiocyanato-stilbene-2,2'-disulphonic acid (DIDS), was reduced by bicuculline to about 80% of control responses, and was antagonized by niflumic acid (NFA) and 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB). We conclude that membrane depolarization increases [Cl(-)](i) via several pathways involving NFA- and NPPB-sensitive anion channels and GABA(A) receptors, but not through furosemide-, bumetanide- or DIDS-sensitive Cl(-) transporters. The present study highlights the vulnerability of [Cl(-)](i) homeostasis after membrane depolarization in neurons.
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Affiliation(s)
- Jennifer E Slemmer
- Laboratory for Neuronal Circuit Dynamics, Brain Science Institute, Riken, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
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Isomura Y, Sugimoto M, Fujiwara-Tsukamoto Y, Yamamoto-Muraki S, Yamada J, Fukuda A. Synaptically activated Cl- accumulation responsible for depolarizing GABAergic responses in mature hippocampal neurons. J Neurophysiol 2004; 90:2752-6. [PMID: 14534278 DOI: 10.1152/jn.00142.2003] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is known that GABA, a major inhibitory transmitter in the CNS, acts as an excitatory (or depolarizing) transmitter transiently after intense GABAA receptor activation in adult brains. The depolarizing effect is considered to be dependent on two GABAA receptor-permeable anions, chloride (Cl-) and bicarbonate (HCO3-). However, little is known about their spatial and temporal profiles during the GABAergic depolarization in postsynaptic neurons. In the present study, we show that the amplitude of synaptically induced depolarizing response was correlated with intracellular Cl- accumulation in the soma of mature hippocampal CA1 pyramidal cells, by using whole cell patch-clamp recording and Cl- imaging technique with a Cl- indicator 6-methoxy-N-ethylquinolinium iodide (MEQ). The synaptically activated Cl- accumulation was mediated dominantly through GABAA receptors. Basket cells, a subclass of fast-spiking interneurons innervating the somatic portion of the pyramidal cells, actually fired at high frequency during the Cl- accumulation accompanying the depolarizing responses. These results suggest synaptically activated GABAA-mediated Cl- accumulation may play a critical role in generation of an excitatory GABAergic response in the mature pyramidal cells receiving intense synaptic inputs. This may be the first demonstration of microscopic visualization of intracellular Cl- accumulation during synaptic activation.
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Affiliation(s)
- Y Isomura
- Department of System Neuroscience, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Tokyo 183-8526, Japan.
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Ikeda M, Toyoda H, Yamada J, Okabe A, Sato K, Hotta Y, Fukuda A. Differential development of cation-chloride cotransporters and Cl- homeostasis contributes to differential GABAergic actions between developing rat visual cortex and dorsal lateral geniculate nucleus. Brain Res 2003; 984:149-59. [PMID: 12932849 DOI: 10.1016/s0006-8993(03)03126-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A recent study suggested that gamma-aminobutyric acid (GABA) plays differential roles in activity-dependent plasticity between the visual cortex (VC) and the dorsal lateral geniculate nucleus (dLGN). In the present study, to investigate differential GABAergic functions in postnatal visual system development, the development of [Cl(-)](i), cation-Cl(-) cotransporter expression, and the [Ca(2+)](i) responses evoked by GABA were compared between VC and dLGN during the early stages of development. Using rat brain slices from postnatal days (P) 0-17, GABA-evoked [Ca(2+)](i) responses and resting [Cl(-)](i) were measured by means of optical imaging of Ca(2+) and Cl(-), respectively. Changes in the expression of cation-Cl(-) cotransporters (viz. the outwardly-directed K(+)-Cl(-) cotransporter, KCC2, and the inwardly-directed Na(+),K(+)-2Cl(-) cotransporter, NKCC1) were examined in VC and dLGN by in situ hybridization. At birth, the excitatory actions of GABA were powerful in VC, but missing in dLGN (as indicated by neuronal [Ca(2+)](i) transients), and the resting [Cl(-)](i) was significantly higher in VC than in dLGN. Signals for KCC2 mRNA expression were significantly higher in dLGN than in VC at P0. This suggests that extrusion of Cl(-) from neurons is stronger in dLGN than in VC at P0, so that a GABAergic excitatory effect was not observed in dLGN because of more negative equilibrium potential for Cl(-). The present study indicates clear differences in the molecular and physiological bases of Cl(-) homeostasis and GABA actions between the developing VC and dLGN. Such differential GABAergic actions may underlie the distinct mechanisms involved in VC and dLGN development within the visual system.
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Affiliation(s)
- Masahiko Ikeda
- Department of Physiology, Hamamatsu University School of Medicine, Hamamatsu, 431-3192, Shizuoka, Japan
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Schomberg SL, Bauer J, Kintner DB, Su G, Flemmer A, Forbush B, Sun D. Cross talk between the GABA(A) receptor and the Na-K-Cl cotransporter is mediated by intracellular Cl-. J Neurophysiol 2003; 89:159-67. [PMID: 12522168 DOI: 10.1152/jn.00229.2002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It has been suggested that the GABA(A) receptor-mediated depolarization in immature neurons depends on a high intracellular Cl(-) concentration maintained by Na-K-Cl cotransporter isoform1 (NKCC1). We previously found that activation of the GABA(A) receptor led to stimulation of NKCC1. This stimulation could be a result of GABA(A) receptor-mediated Cl(-) efflux. However, a loss of intracellular Cl(-) is associated with cell shrinkage, membrane depolarization, as well as a rise of intracellular Ca(2+) concentration ([Ca(2+)](i)). To determine which cellular mechanism is underlying NKCC1 stimulation, we investigated changes of intracellular Cl(-) content, [Ca(2+)](i), cell volume, and NKCC1 activity following GABA(A) receptor activation. The basal levels of intracellular (36)Cl were 0.70 +/- 0.04 micromol/mg protein. The intracellular (36)Cl content decreased to 0.53 +/- 0.03 micromol/mg protein in response to 30 microM muscimol (P < 0.05). The loss of intracellular (36)Cl was blocked by 10 microM bicuculline. Muscimol triggered a rise in [Ca(2+)](i), but did not cause cell shrinkage. In contrast, 10-50 mM [Cl(-)](o) or hypertonic HEPES-MEM resulted in reversible cell shrinkage (P < 0.05). Moreover, the GABA-mediated stimulation of NKCC1 activity was not abolished either by removal of extracellular Ca(2+) or BAPTA-AM. An increase in phosphorylation of NKCC1 was detected under both 10 mM [Cl(-)](o) and muscimol conditions. These results suggest that a GABA-mediated loss of intracellular Cl(-), but not a subsequent rise in [Ca(2+)](i) or shrinkage, leads to stimulation of NKCC1. This stimulation may be an important positive feedback mechanism to maintain intracellular Cl(-) level and GABA function in immature neurons.
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Affiliation(s)
- Stacey L Schomberg
- Department of Neurological Surgery, University of Wisconsin Medical School, Madison 53792, USA
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Kang TC, An SJ, Park SK, Hwang IK, Yoon DK, Shin HS, Won MH. Changes in Na(+)-K(+)-Cl(-) cotransporter immunoreactivity in the gerbil hippocampus following transient ischemia. Neurosci Res 2002; 44:249-54. [PMID: 12413653 DOI: 10.1016/s0168-0102(02)00131-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We examined alterations in Na(+)-K(+)-Cl(-) cotransporter 1 (NKCC1) immunoreactivity following ischemia. Twelve hours after ischemia, NKCC1 immunoreactivity in the CA1 region and in the hilar region was significantly diminished. Twenty-four hours after ischemia, NKCC1 immunoreactivity was intensified in these hippocampal regions as well as CA2-3. Two days after ischemia, NKCC1 immunoreactivity in the CA1 and the hilar neurons had disappeared, although in the CA2-3 and the granule cell layer NKCC1 immunoreactivities had recovered to the sham level. This finding suggests that NKCC1 may play an important role in the ischemic neuronal injury induced by excitotoxicity as well as neuronal edema.
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Affiliation(s)
- Tae Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Kangwon-Do 200-702, Chunchon, Republic of Korea
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