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[Accumulation of Ca ions in intracellular structures of rat myometrium during subacute, acute, and chronic administration of ethanol]

https://arctichealth.org/en/permalink/ahliterature10292
Source
Ukr Biokhim Zh. 2000 May-Jun;72(3):44-55
Publication Type
Article
Author
L A Borisova
L G Babich
S G Shlykov
S A Kosterin
Author Affiliation
A. V. Palladin Institute of Biochemistry, NAS of Ukraine, Kyiv.
Source
Ukr Biokhim Zh. 2000 May-Jun;72(3):44-55
Language
Russian
Publication Type
Article
Keywords
Animals
Calcium - metabolism
Endoplasmic Reticulum - metabolism
English Abstract
Ethanol - administration & dosage - pharmacology
Female
Mitochondria - metabolism
Myometrium - drug effects - metabolism
Rats
Abstract
The effects of subacute, acute and chronic ethanol exposure on the activity of Ca(2+)-accumulating systems of mitochondria and endoplasmic reticulum in myometrial cells of nonpregnant estrogen-treated rats were studied. It has been shown that the activity of Ca(2+)-accumulating system of mitochondria was higher than the activity of Ca(2+)-accumulating system of endoplasmic reticulum in myometrial cells from control, acute and subacute treated with ethanol rats. Under ethanol chronical assumption both Ca(2+)-accumulation in mitochondria and Ca(2+)-transporting activity of endoplasmic reticulum are inhibited. In the latter ease Mg2+, ATP-dependent Ca(2+)-pump lost its sensitivity to oxytocin.
PubMed ID
11200474 View in PubMed
Less detail

Activation of P2-purino-, alpha 1-adreno and H1-histamine receptors triggers cytoplasmic calcium signalling in cerebellar Purkinje neurons.

https://arctichealth.org/en/permalink/ahliterature11198
Source
Neuroscience. 1996 Aug;73(3):643-7
Publication Type
Article
Date
Aug-1996
Author
S. Kirischuk
V. Matiash
A. Kulik
N. Voitenko
P. Kostyuk
A. Verkhratsky
Author Affiliation
Bogomoletz Institute of Physiology, Kiev, Ukraine.
Source
Neuroscience. 1996 Aug;73(3):643-7
Date
Aug-1996
Language
English
Publication Type
Article
Keywords
Adenosine Triphosphate - pharmacology
Animals
Calcium - metabolism
Cerebellum - drug effects
Dose-Response Relationship, Drug
Epinephrine - pharmacology
Histamine - pharmacology
Mice
Mice, Inbred Strains
Purkinje Cells - drug effects
Receptors, Adrenergic, alpha-1 - drug effects
Receptors, Histamine - drug effects
Receptors, Purinergic - drug effects
Research Support, Non-U.S. Gov't
Abstract
The cytoplasmic calcium concentration ([Ca2+]i) was measured from Purkinje neurons in acutely prepared cerebellar slices. Neurons were loaded with calcium indicator Fura-2 by 40-min slice incubation in Tyrode solution containing 5 microM Fura-2/AM and 0.02% pluronic-F127. Bath applications of ATP (100 microM), epinephrine (10 microM) and histamine (100 microM) triggered a transient increase of [Ca2+]i in Purkinje neurons. ATP-induced [Ca2+]i elevation in Purkinje neurons was mimicked by ADP, but not AMP or adenosine pointing to the involvement of P2Y metabotropic purinoreceptors. Epinephrine-triggered [Ca2+]i responses were blocked by the selective alpha 1-antagonist prazosin and were mimicked by the alpha 1-adrenoreceptor agonist phenylephrine, and were not affected by beta- and alpha 2-adrenoreceptor agonists (isoproterenol and clonidine) and antagonists (propranolol and yohimbine). Histamine-induced [Ca2+]i responses demonstrated specific sensitivity to selective H1 antagonist chlorpheniramine, and were not sensitive to H2 and H3 histamine receptors modulators. The [Ca2+]i responses to all three agonists persisted in Ca(2+)-free extracellular media and were blocked by slice preincubation with thapsigargin (500 nM). We conclude that cerebellar Purkinje neurons are endowed with metabotropic P2 gamma purinoreceptors, alpha 1-adrenoreceptors and H1 histamine receptors which mediate the generation of intracellular [Ca2+]i signals via activation of Ca2+ release from inositol-1,4,5-trisphosphate-sensitive intracellular stores.
PubMed ID
8809785 View in PubMed
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Adaptation of Inuit children to a low-calcium diet.

https://arctichealth.org/en/permalink/ahliterature4790
Source
CMAJ. 2003 Apr 29;168(9):1141-3
Publication Type
Article
Date
Apr-29-2003
Author
Elizabeth A C Sellers
Atul Sharma
Celia Rodd
Author Affiliation
Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Man.
Source
CMAJ. 2003 Apr 29;168(9):1141-3
Date
Apr-29-2003
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Adolescent
Calcium - metabolism - urine
Child
Child Welfare
Child, Preschool
Diet
Female
Humans
Intestinal Absorption
Inuits
Male
Research Support, Non-U.S. Gov't
Vitamin D - metabolism
Abstract
For Inuit children, a traditional diet contains 20 mg of elemental calcium per day, well below the recommended daily intake. To identify alterations in intestinal or renal calcium absorption, 10 healthy Inuit children (5 to 17 years of age) were given a standardized calcium load (Pak test). Five had hypercalciuria (hyperabsorptive in 3 and renal leak in 2), a frequency markedly different from that for white children (p
Notes
Comment In: CMAJ. 2003 Sep 16;169(6):542; author reply 542-312975217
Erratum In: CMAJ. 2003 Sep 16;169(6):545
PubMed ID
12719317 View in PubMed
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An intact actin-containing cytoskeleton is required for capacitative calcium entry, but not for ATP-induced calcium-mediated cell signaling in cultured human keratinocytes.

https://arctichealth.org/en/permalink/ahliterature18348
Source
Med Sci Monit. 2003 Jun;9(6):BR199-207
Publication Type
Article
Date
Jun-2003
Author
Timo Korkiamäki
Heli Ylä-Outinen
Jussi Koivunen
Juha Peltonen
Author Affiliation
Department of Anatomy and Cell Biology, University of Oulu, Oulu, Finland. tkorkiam@paju.oulu.fi
Source
Med Sci Monit. 2003 Jun;9(6):BR199-207
Date
Jun-2003
Language
English
Publication Type
Article
Keywords
Actins - physiology
Adenosine Triphosphate - pharmacology
Adult
Biological Transport
Calcium - metabolism - pharmacology - physiology
Cells, Cultured
Cytochalasin D - pharmacology
Cytoskeleton - drug effects - physiology - ultrastructure
Humans
Keratinocytes - cytology - drug effects - physiology
Middle Aged
Neurofibromatosis 1 - pathology
Research Support, Non-U.S. Gov't
Signal Transduction - drug effects - physiology
Skin - cytology - drug effects
Thapsigargin - pharmacology
Abstract
BACKGROUND: The present study was focused on structural relationship between intracellular calcium stores and plasma membrane store-operated calcium channels in cultured normal and NF1 keratinocytes. MATERIAL/METHODS: Calcium mobilization induced by thapsigargin or extracellular ATP was studied in control and cytochalasin D-treated human keratinocytes. RESULTS: Treatment of keratinocytes with cytochalasin D disrupted the actin cytoskeleton and changed the cells from a planar, extended morphology, to a rounded shape. In normal control keratinocytes, thapsigargin induced a marked increase in intracellular calcium concentration ([Ca2+]i). The capacitative calcium influx of cytochalasin D-treated normal keratinocytes was significantly weaker compared to normal control cells. In normal keratinocytes, ATP induced a rapid and transient increase in [Ca2+]i. Thus disruption of the cytoskeleton blocked thapsigargin-induced calcium mobilization, but had no effect on ATP-induced [Ca2+]i mobilization in keratinocytes. The results suggest that microfilaments play crucial role for functional capacitative Ca2+ entry in cultured keratinocytes. The cytoskeleton and calcium mediated cell signaling have been demonstrated to be abnormal in keratinocytes cultured from patients with neurofibromatosis type 1 (NF1). In NF1 keratinocytes, thapsigargin induced a slow and moderate increase in [Ca2+]i. The effect of cytochalasin D on NF1 keratinocytes was less pronounced compared to normal keratinocytes. In NF1 keratinocytes, ATP induced a rapid and transient increase in [Ca2+]i. CONCLUSIONS: The actin microfilaments play a crucial role for functional capacitative Ca2+ entry in cultured keratinocytes, and that aberrant organization of cytoskeleton may partly explain altered calcium-mediated cell signaling in NF1.
PubMed ID
12824940 View in PubMed
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Arctic mutant Aß40 aggregates on a7 nicotinic acetylcholine receptors and inhibits their functions.

https://arctichealth.org/en/permalink/ahliterature259619
Source
J Neurochem. 2014 Dec;131(5):667-74
Publication Type
Article
Date
Dec-2014
Author
Ye Ju
Toru Asahi
Naoya Sawamura
Source
J Neurochem. 2014 Dec;131(5):667-74
Date
Dec-2014
Language
English
Publication Type
Article
Keywords
Amyloid beta-Peptides - genetics
Animals
CHO Cells
Calcium - metabolism
Cricetulus
Humans
Microscopy, Electron, Transmission
Mutation - genetics
Peptide Fragments - genetics
Protein Aggregates - genetics
Protein Binding - genetics
Transfection
alpha7 Nicotinic Acetylcholine Receptor - metabolism - ultrastructure
Abstract
Amyloid ß protein (Aß) plays a central role in the pathogenesis of Alzheimer's disease (AD). Point mutations within the Aß sequence associated with familial AD (FAD) are clustered around the central hydrophobic core of Aß. Several types of mutations within the Aß sequence have been identified, and the 'Arctic' mutation (E22G) has a purely cognitive phenotype typical of AD. Previous studies have shown that the primary result of the 'Arctic' mutation is increased formation of Aß protofibrils. However, the molecular mechanism underlying this effect remains unknown. Aß42 binds to a neuronal nicotinic acetylcholine receptor subunit, neuronal acetylcholine receptor subunit alpha-7 (CHRNA7), with high affinity and, thus, may be involved in the pathogenesis of AD. Therefore, to clarify the molecular mechanism of Arctic mutation-mediated FAD, we focused on CHRNA7 as a target molecule of Arctic Aß. We performed an in vitro binding assay using purified CHRNA7 and synthetic Arctic Aß40, and demonstrated that Arctic Aß40 specifically bound to CHRNA7. The aggregation of Arctic Aß40 was enhanced with the addition of CHRNA7. Furthermore, the function of CHRNA7 was detected by measuring Ca(2+) flux and phospho-p44/42 MAPK (ERK1/2) activation. Our results indicated that Arctic Aß40 aggregation was enhanced by the addition of CHRNA7, which destabilized the function of CHRNA7 via inhibition of Ca(2+) responses and activation of ERK1/2. These findings indicate that Arctic Aß mutation may be involved in the mechanism underlying FAD. This mechanism may involve binding and aggregation, leading to the inhibition of CHRNA7 functions.
PubMed ID
25059095 View in PubMed
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ATP-induced cytoplasmic calcium mobilization in Bergmann glial cells.

https://arctichealth.org/en/permalink/ahliterature11322
Source
J Neurosci. 1995 Dec;15(12):7861-71
Publication Type
Article
Date
Dec-1995
Author
S. Kirischuk
T. Möller
N. Voitenko
H. Kettenmann
A. Verkhratsky
Author Affiliation
Bogomoletz Institute of Physiology, Kiev-24, Ukraine.
Source
J Neurosci. 1995 Dec;15(12):7861-71
Date
Dec-1995
Language
English
Publication Type
Article
Keywords
Adenosine Triphosphate - pharmacology
Animals
Biological Transport - drug effects
Calcium - metabolism
Cerebellum - cytology - metabolism
Cytoplasm - metabolism
Inositol 1,4,5-Trisphosphate - pharmacology
Mice
Neuroglia - metabolism
Osmolar Concentration
Receptors, Purinergic P2 - metabolism
Research Support, Non-U.S. Gov't
Subcellular Fractions - metabolism
Abstract
ATP receptor mediated Ca2+ signaling was recorded from Bergmann glial cells in cerebellar slices obtained from mice of different ages (postnatal days 6 to 45). To measure the cytoplasmic concentration of Ca2+ ([Ca2+]in), either individual cells were loaded with the Ca(2+)-sensitive probes using the whole cell patch clamp technique or slices were incubated with the dye and the microfluorimetric system was focused on individual cells. Signals were recorded either with single-detector microfluorimetry of the dye fura-2 or by confocal laser scanning microfluorimetry (fluo-3-based recordings). Extracellular application of 100 microns ATP caused a transient elevation of [Ca2+]in, which amplitude was significantly higher in Bergmann glial cell processes as compared with their soma. The rank order of potency for the purinoreceptor agonists was: ADP > or = ATP > UTP >> AMP = adenosine = alpha, beta-methylene-ATP. ATP-triggered Ca2+ transients were reversibly inhibited by the P2 purinoreceptor agonist suramin (100 microM). The involvement of P2 metabotropic receptors is inferred by the observation that ATP mediated cytoplasmic Ca2+ transients were not associated with a measurable change in membrane conductance. The [Ca2+]in increase was due to release from inositol-1,4,5-trisphosphate (InsP3)-sensitive intracellular stores since responses were still observed in Ca(2+)-free extracellular solutions and were irreversibly blocked by the inhibitor of the sarco(endo)plasmic reticulum Ca2+ ATPase, thapsigargin, and by the competitive inhibitor of the InsP3-gated intracellular Ca2+ channels heparin. Intracellular dialysis altered the refilling process of the InsP3-sensitive stores, suggesting that cytoplasmic factors control ATP mediated Ca2+ signalling.
PubMed ID
8613725 View in PubMed
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ATP induces Ca2+ release from IP3-sensitive Ca2+ stores exclusively in large DRG neurones.

https://arctichealth.org/en/permalink/ahliterature11053
Source
Neuroreport. 1997 May 6;8(7):1555-9
Publication Type
Article
Date
May-6-1997
Author
N. Svichar
A. Shmigol
A. Verkhratsky
P. Kostyuk
Author Affiliation
Bogomoletz Institute of Physiology, Kiev, Ukraine.
Source
Neuroreport. 1997 May 6;8(7):1555-9
Date
May-6-1997
Language
English
Publication Type
Article
Keywords
Adenosine Triphosphate - pharmacology
Animals
Calcium - metabolism
Ganglia, Spinal - cytology - drug effects - metabolism
In Vitro
Inositol 1,4,5-Trisphosphate - pharmacology
Mice
Neurons - drug effects
Receptors, Purinergic P2 - metabolism
Research Support, Non-U.S. Gov't
Abstract
PURINORECEPTOR-MEDIATED intracellular Ca2+ release was studied in freshly isolated adult mouse dorsal root ganglia (DRG) neurones. The cytoplasmic Ca2+ concentration ([Ca2+]i) was measured using indo-1-based microfluorimetry. The application of 100 microM ATP in Ca(2+)-free solution triggered an increase in [Ca2+]i in 93% of large DRG neurones but in no small ones. The ATP-induced [Ca2+]i transients in large neurones were inhibited by cells incubation with thapsigargin or by intracellular dialysis with heparin-containing solution. The ATP-triggered increase in [Ca2+]i was not mimicked by adenosine and was blocked by suramin, suggesting the involvement of metabotropic (PZY) purinoreceptors. We conclude that large (proprioceptive) DRG neurones express PZY purinoreceptors linked to the inositol 1,4,5-triphosphate-Ca2+ intracellular signal transduction cascade, whereas small (nociceptive) DRG neurones are devoid of such a mechanism.
PubMed ID
9189891 View in PubMed
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Bioenergetics and permeability transition pore opening in heart subsarcolemmal and interfibrillar mitochondria: effects of aging and lifelong calorie restriction.

https://arctichealth.org/en/permalink/ahliterature89070
Source
Mech Ageing Dev. 2009 May;130(5):297-307
Publication Type
Article
Date
May-2009
Author
Hofer Tim
Servais Stephane
Seo Arnold Young
Marzetti Emanuele
Hiona Asimina
Upadhyay Shashank Jagdish
Wohlgemuth Stephanie Eva
Leeuwenburgh Christiaan
Author Affiliation
Department of Aging and Geriatric Research, College of Medicine, Institute on Aging, Division of Biology of Aging, University of Florida, Gainesville, FL 32610, USA. tim.hofer@comhem.se
Source
Mech Ageing Dev. 2009 May;130(5):297-307
Date
May-2009
Language
English
Publication Type
Article
Keywords
Animals
Calcium - metabolism
Caloric Restriction
Caspase 3 - metabolism
Caspase 9 - metabolism
Cell Membrane Permeability
Cyclophilins - metabolism
Cytochromes c - metabolism
Electron Transport Complex IV - metabolism
Energy Metabolism
Hydrogen Peroxide - metabolism
Longevity
Male
Mitochondria, Heart - metabolism
Mitochondrial ADP, ATP Translocases - metabolism
Myocardium - metabolism - ultrastructure
Oxygen consumption
Rats
Rats, Inbred BN
Rats, Inbred F344
Sarcolemma - metabolism - ultrastructure
Abstract
Loss of cardiac mitochondrial function with age may cause increased cardiomyocyte death through mitochondria-mediated release of apoptogenic factors. We investigated ventricular subsarcolemmal (SSM) and interfibrillar (IFM) mitochondrial bioenergetics and susceptibility towards Ca(2+)-induced permeability transition pore (mPTP) opening with aging and lifelong calorie restriction (CR). Cardiac mitochondria were isolated from 8-, 18-, 29- and 37-month-old male Fischer 344 x Brown Norway rats fed either ad libitum (AL) or 40% calorie restricted diets. With age, H(2)O(2) generation did not increase and oxygen consumption did not significantly decrease in either SSM or IFM. Strikingly, IFM displayed an increased susceptibility towards mPTP opening during senescence. In contrast, Ca(2+) retention capacity of SSM was not affected by age, but SSM tolerated much less Ca(2+) than IFM. Only modest age-dependent increases in cytosolic caspase activities and cytochrome c levels were observed and were not affected by CR. Levels of putative mPTP-modulating components: cyclophilin-D, the adenine nucleotide translocase (ANT), and the voltage-dependent ion channel (VDAC) were not affected by aging or CR. In summary, the age-related reduction of Ca(2+) retention capacity in IFM may explain the increased susceptibility to stress-induced cell death in the aged myocardium.
PubMed ID
19428447 View in PubMed
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164 records – page 1 of 17.