A5100414801- Ion channel regulation and function
- Neuroscience of respiration and sleep
- Cardiac electrophysiology and arrhythmias
- Neuroscience and Neuropharmacology Research
- High Altitude and Hypoxia
- Ion Channels and Receptors
- Hemoglobin structure and function
- Nitric Oxide and Endothelin Effects
- Ion Transport and Channel Regulation
- Receptor Mechanisms and Signaling
- Sleep and Wakefulness Research
- Heart Rate Variability and Autonomic Control
- Nicotinic Acetylcholine Receptors Study
- Neurobiology and Insect Physiology Research
- Biochemical Analysis and Sensing Techniques
- Restraint-Related Deaths
- Neuroscience and Neural Engineering
- Sulfur Compounds in Biology
- Cancer, Hypoxia, and Metabolism
- Cardiac Ischemia and Reperfusion
- Olfactory and Sensory Function Studies
- Advanced Chemical Sensor Technologies
- Postharvest Quality and Shelf Life Management
- Mitochondrial Function and Pathology
- Phytochemicals and Antioxidant Activities
Rosalind Franklin University of Medicine and Science
2014-2024
Boramae Medical Center
2024
Franklin University
2012-2014
Abstract TRPA1 is an ion channel and has been proposed as a thermosensor across species. In invertebrate ancestral vertebrates such fly, mosquito, frog, lizard snakes, serves heat receptor, sensory input utilized for avoidance or infrared detection. However, in mammals, whether receptor noxious cold highly controversial, activation by was observed some groups but disputed others. Here we attribute the discrepancy to species differences. We show that activates rat mouse not human rhesus...
Recently, several mammalian K+channel subunits (TWIK, TREK-1, TRAAK, and TASK) possessing four transmembrane segments two pore-forming domains have been identified. We report the cloning of a new member this tandem-pore K+ channel from rat cerebellum cDNA library. It is 538-amino acid protein shares 65% amino sequence identity with TREK-1. Therefore, clone was named TREK-2. Unlike whose mRNA has reported to be expressed in many different tissues, TREK-2 mainly cerebellum, spleen, testis as...
TREK‐1, TREK‐2 and TRAAK are members of the two‐pore domain K + (K 2P ) channel family activated by membrane stretch free fatty acids. TREK‐1 has been shown to be sensitive temperature in expression systems. We studied temperature‐sensitivity COS‐7 cells neuronal cells. In transfected cells, whole‐cell currents increased ∼20‐fold as bath was raised from 24°C 42°C. Similarly, cell‐attached patches activity very low, but progressively The thresholds for activation were ∼25°C ∼31°C,...
Dorsal root ganglion (DRG) neurons express mRNAs for many two-pore domain K + (K 2P ) channels that behave as background channels. To identify functional in DRG neurons, we examined the properties of single-channel openings from cell-attached and inside-out patches cell bodies neurons. We found seven types channels, with conductance ranging 14 to 120 pS 150 mM KCl bath solution. Four these showed biophysical pharmacological similar TRESK (14 pS), TREK-1 (112 TREK-2 (50 TRAAK (73 which are...
Carotid body (CB) glomus cells from rat express a TASK-like background K+ channel that is believed to play critical role in the regulation of excitability and hypoxia-induced increase respiration. Here we studied kinetic behaviour single openings CB determine molecular identity 'TASK-like' channels. In outside-out patches, was inhibited >90% by reduction pH(o) 7.3 5.8. cell-attached patches with 140 mM KCl 1 Mg2+ bath pipette solutions, two main open levels conductance approximately 14 pS 32...
TASK-1 and TASK-3 are functional members of the tandem-pore K+ (K2P) channel family, mRNAs for both channels expressed together in many brain regions. Although subunits able to form heteromers when their complementary RNAs injected into oocytes, whether present native tissue is not known. Using cultured cerebellar granule (CG) neurones that express TASK-3, we studied presence by comparing sensitivities cloned extracellular pH (pHo) ruthenium red. The single-channel conductance TASK-1, a...
Background: A number of prostaglandins (PGs) sensitize dorsal root ganglion (DRG) neurons and contribute to inflammatory hyperalgesia by signaling through specific G protein-coupled receptors (GPCRs). One mechanism whereby PGs these is modulation “thermoTRPs,” a subset ion channels activated temperature belonging the Transient Receptor Potential channel superfamily. Acrid, electrophilic chemicals including cinnamaldehyde (CA) allyl isothiocyanate (AITC), derivatives cinnamon mustard oil...
Abundantly expressed in pain-sensing neurons, TRPV1, TRPA1 and TRPM8 are major cellular sensors of thermal, chemical mechanical stimuli. The function these ion channels has been attributed to their selective permeation small cations (e.g., Ca2+, Na+ K+), the selectivity assumed be an invariant fingerprint a given channel. However, for notion revised recently. When activated, TRPV1 undergoes time agonist-dependent pore dilation, allowing large organic such as Yo-Pro NMDG+. dilation is...
Cerebellar granule neurons express a standing outward (background) K + current ( I K,SO ) that regulates the resting membrane potential and cell excitability. As several tandem‐pore (2P) channel mRNAs are highly expressed in cerebellar cells, we studied whether, which, 2P channels contribute to . was sensitive changes extracellular pH partially inhibited by acetylcholine, as reported previously. In cell‐attached patches from cultured neurons, four types of were found be active when held at...
A mammalian K(+) channel subunit (TBAK-1/TASK-1) containing two pore domains and four transmembrane segments whose mRNA is highly expressed in the heart has been cloned recently. TBAK-1 TASK-1 are identical except for additional nine amino acids NH(2) terminus of TBAK-1. We examined their kinetic properties, pH sensitivity, regional cardiac expression determined whether a native with similar properties was present. When or transiently COS-7 cells, time- voltage-independent whole cell...
Membrane phosphatidylinositol-4,5-bisphosphate (PIP2) is critical for the function of many transient receptor potential (TRP) ion channels. The role PIP2 in TRPA1 not well known. effect on was investigated by direct application and using polylysine antibody that sequester PIP2. In inside-out patches from HeLa cells expressing mouse TRPA1, polytriphosphate (PPPi) added to bath solution keep sensitive allyl isothiocyanate (AITC; mustard oil). Direct (10 μM) did activate but AITC Δ 9...
A new member of the tandem-pore K+ (K2P) channel family has been isolated from mouse testis complementary DNA. The K2P was named TRESK-2, as its amino acid sequence shares 65% identity with that TRESK-1. Mouse TRESK-2 is a 394-amino protein and possesses four putative transmembrane segments two pore-forming domains. long cytoplasmic domain joining second third short carboxyl terminus. In rat, mRNA transcripts were expressed abundantly in thymus spleen at low levels many other tissues,...
TREK-2 expressed in mammalian cells exhibits small ( approximately 52 pS) and large 220 unitary conductance levels. Here we tested the role of N-terminus (69 amino acids long) control conductance, alternative translation initiation as a mechanism that produces isoforms show different Deletion first half (Delta1-36) had no effect. However, deletion most (Delta1-66) resulted appearance only large-conductance channel pS). In support critical function distal N-terminus, mutants Delta1-44...
Ca2+ signaling plays a fundamental role in cardiac hypertrophic remodeling, but the underlying mechanisms remain poorly understood. We investigated of Ca2+-mobilizing second messengers, NAADP and cADPR, hypertrophy induced by β-adrenergic stimulation isoproterenol. Isoproterenol an initial transients followed sustained rises. Inhibition cADPR pathway with 8-Br-cADPR abolished only increase, whereas inhibition bafilomycin-A1 both rapid phases isoproterenol-mediated signal, indicating that...
Magnocellular neurosecretory cells (MNCs) were isolated from the supraoptic nucleus of rat hypothalamus, and properties K + channels that may regulate resting membrane potential excitability MNCs studied. showed large transient outward currents, typical vasopressin‐ oxytocin‐releasing neurons. in identified by recording open at rest cell‐attached inside‐out patches symmetrical 150 m KCl. Eight different could be distinguished unambiguously their single‐channel kinetics voltage‐dependent...
TREK-2 is a member of the two-pore domain K(+) channel family and provides part background current in many types cells. Neurotransmitters that act on receptors coupled to G(q) strongly inhibit thus enhance cell excitability. The molecular basis for inhibition was studied. In COS-7 cells expressing M(3) receptor, acetylcholine (ACh) applied bath solution inhibited whole current, this markedly reduced presence U-73122, an inhibitor PLC. also observed cell-attached patches when ACh solution....
Importance Many epidemiologic studies have suggested that low levels of plasma leptin, a major adipokine, are associated with increased risk Alzheimer disease (AD) dementia and cognitive decline. Nevertheless, the mechanistic pathway linking leptin AD-related decline is not yet fully understood. Objective To examine association in vivo AD pathologies, including amyloid-beta (Aβ) tau deposition, through both cross-sectional longitudinal approaches among cognitively unimpaired older adults....