4-Hydroxynonenal dependent alteration of TRPV1-mediated coronary microvascular signaling.
*4-Hydroxynonenal; *Coronary regulation; *Lipid peroxidation; *Post-translational modification; *Protein Processing; *Reactive oxygen species; *Signal Transduction; *TRPV1; Action Potentials/drug effects; Aldehydes/antagonists & inhibitors/metabolism/*pharmacology; Animal; Animals; Blood Flow Velocity; Calcium Signaling/drug effects; Capsaicin/*pharmacology; Cardiovascular Agents/*pharmacology; Coronary Circulation/drug effects; Coronary Vessels/metabolism/physiopathology; Cysteine/genetics/metabolism; Diabetes Mellitus/drug therapy/*metabolism/physiopathology; Disease Models; Femoral Artery/metabolism/physiopathology; HEK293 Cells; Humans; Inbred C57BL; Lipid Peroxidation; Male; Mice; Patch-Clamp Techniques; Post-Translational; TRPV Cation Channels/genetics/*metabolism; Vasodilation/drug effects
We demonstrated previously that TRPV1-dependent regulation of coronary blood flow (CBF) is disrupted in diabetes. Further, we have shown that endothelial TRPV1 is differentially regulated, ultimately leading to the inactivation of TRPV1, when exposed to a prolonged pathophysiological oxidative environment. This environment has been shown to increase lipid peroxidation byproducts including
DelloStritto Daniel J; Sinharoy Pritam; Connell Patrick J; Fahmy Joseph N; Cappelli Holly C; Thodeti Charles K; Geldenhuys Werner J; Damron Derek S; Bratz Ian N
Free radical biology & medicine
2016
2016-12
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.freeradbiomed.2016.09.021" target="_blank" rel="noreferrer noopener">10.1016/j.freeradbiomed.2016.09.021</a>
Differential regulation of TRPV1 channels by H2O2: implications for diabetic microvascular dysfunction.
*Coronary Circulation; *Microcirculation; Animals; Capsaicin; Coronary blood flow; Diabetic Angiopathies/*metabolism; HEK293 Cells; Humans; Hydrogen peroxide; Hydrogen Peroxide/*metabolism; Inbred C57BL; Knockout; Male; Mice; Reactive oxygen species; TRPV Cation Channels/*metabolism; TRPV1
We demonstrated previously that TRPV1-dependent coupling of coronary blood flow (CBF) to metabolism is disrupted in diabetes. A critical amount of H2O2 contributes to CBF regulation; however, excessive H2O2 impairs responses. We sought to determine the extent to which differential regulation of TRPV1 by H2O2 modulates CBF and vascular reactivity in diabetes. We used contrast echocardiography to study TRPV1 knockout (V1KO), db/db diabetic, and wild type C57BKS/J (WT) mice. H2O2 dose-dependently increased CBF in WT mice, a response blocked by the TRPV1 antagonist SB366791. H2O2-induced vasodilation was significantly inhibited in db/db and V1KO mice. H2O2 caused robust
DelloStritto Daniel J; Connell Patrick J; Dick Gregory M; Fancher Ibra S; Klarich Brittany; Fahmy Joseph N; Kang Patrick T; Chen Yeong-Renn; Damron Derek S; Thodeti Charles K; Bratz Ian N
Basic research in cardiology
2016
2016-03
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1007/s00395-016-0539-4" target="_blank" rel="noreferrer noopener">10.1007/s00395-016-0539-4</a>
Disruption of TRPV1-mediated coupling of coronary blood flow to cardiac metabolism in diabetic mice: role of nitric oxide and BK channels.
13-dienoic Acid/pharmacology; 15-Hydroxy-11 alpha; 9 alpha-(epoxymethano)prosta-5; Anilides/pharmacology; Animals; Capsaicin/analogs & derivatives/pharmacology; Cinnamates/pharmacology; Coronary Vessels/drug effects/*metabolism/physiopathology; Diabetes Mellitus; Diabetic Cardiomyopathies/drug therapy/*metabolism; Enzyme Inhibitors/pharmacology; Inbred C57BL; Large-Conductance Calcium-Activated Potassium Channels/antagonists & inhibitors/*metabolism; Male; Mice; Microvessels/drug effects/physiopathology; NG-Nitroarginine Methyl Ester/pharmacology; Nitric Oxide/*metabolism; Peptides/pharmacology; TRPV Cation Channels/agonists/antagonists & inhibitors/biosynthesis/*metabolism; Type 2/drug therapy/*metabolism; Vasoconstrictor Agents/pharmacology; Vasodilation/drug effects
We have previously shown transient receptor potential vanilloid subtype 1 (TRPV1) channel-dependent coronary function is compromised in pigs with metabolic syndrome (MetS). However, the mechanisms through which TRPV1 channels couple coronary blood flow to metabolism are not fully understood. We employed mice lacking TRPV1 [TRPV1((-/-))], db/db diabetic, and control C57BKS/J mice to determine the extent to which TRPV1 channels modulate coronary function and contribute to vascular dysfunction in diabetic cardiomyopathy. Animals were subjected to in vivo infusion of the TRPV1 agonist capsaicin to examine the hemodynamic actions of TRPV1 activation. Capsaicin (1-100 mug.kg(-1).min(-1)) dose dependently increased coronary blood flow in control mice, which was inhibited by the TRPV1 antagonist capsazepine or the nitric oxide synthase (NOS) inhibitor N-nitro-l-arginine methyl ester (L-NAME). In addition, the capsaicin-mediated increase in blood flow was attenuated in db/db mice. TRPV1((-/-)) mice exhibited no changes in coronary blood flow in response to capsaicin. Vasoreactivity studies in isolated pressurized mouse coronary microvessels revealed a capsaicin-dependent relaxation that was inhibited by the TRPV1 inhibitor SB366791 l-NAME and to the large conductance calcium-sensitive potassium channel (BK) inhibitors iberiotoxin and Penetrim A. Similar to in vivo responses, capsaicin-mediated relaxation was impaired in db/db mice compared with controls. Changes in pH (pH 7.4-6.0) relaxed coronary vessels contracted to the thromboxane mimetic U46619 in all three groups of mice; however, pH-mediated relaxation was blunted in vessels obtained from TRPV1((-/-)) and db/db mice compared with controls. Western blot analysis revealed decreased myocardial TRPV1 protein expression in db/db mice compared with controls. Our data reveal TRPV1 channels mediate coupling of myocardial blood flow to cardiac metabolism via a nitric oxide-dependent, BK channel-dependent pathway that is corrupted in diabetes.
Guarini Giacinta; Ohanyan Vahagn A; Kmetz John G; DelloStritto Daniel J; Thoppil Roslin J; Thodeti Charles K; Meszaros J Gary; Damron Derek S; Bratz Ian N
American journal of physiology. Heart and circulatory physiology
2012
2012-07
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/ajpheart.00011.2012" target="_blank" rel="noreferrer noopener">10.1152/ajpheart.00011.2012</a>
Endothelin-mediated in vivo pressor responses following TRPV1 activation.
*Blood Pressure/drug effects; *Vasoconstriction/drug effects; Adrenergic alpha-Agonists/administration & dosage; Analysis of Variance; Animal; Animals; Azepines/administration & dosage; Biphenyl Compounds/administration & dosage; Capsaicin/administration & dosage; Cells; Cultured; Diabetes Mellitus; Diabetic Angiopathies/genetics/*metabolism/physiopathology; Dipeptides/administration & dosage; Disease Models; Dose-Response Relationship; Drug; Endothelial Cells/metabolism; Endothelin A Receptor Antagonists; Endothelin A/metabolism; Endothelin B Receptor Antagonists; Endothelin B/metabolism; Endothelin-1/*metabolism; Enzyme-Linked Immunosorbent Assay; Femoral Artery/drug effects/*metabolism/physiopathology; Inbred C57BL; Indoles/administration & dosage; Infusions; Intravenous; Knockout; Male; Mice; Phenylephrine/administration & dosage; Receptor; TRPV Cation Channels/agonists/deficiency/genetics/*metabolism; Type 2/genetics/*metabolism/physiopathology; Vasoconstrictor Agents/administration & dosage
Transient receptor potential vanilliod 1 (TRPV1) channels have recently been postulated to play a role in the vascular complications/consequences associated with diabetes despite the fact that the mechanisms through which TRPV1 regulates vascular function are not fully known. Accordingly, our goal was to define the mechanisms by which TRPV1 channels modulate vascular function and contribute to vascular dysfunction in diabetes. We subjected mice lacking TRPV1 [TRPV1((-/-))], db/db, and control C57BLKS/J mice to in vivo infusion of the TRPV1 agonist capsaicin or the alpha-adrenergic agonist phenylephrine (PE) to examine the integrated circulatory actions of TRPV1. Capsaicin (1, 10, 20, and 100 mug/kg) dose dependently increased MAP in control mice (5.7 +/- 1.6, 11.7 +/- 2.1, 25.4 +/- 3.4, and 51.6 +/- 3.9%), which was attenuated in db/db mice (3.4 +/- 2.1, 3.9 +/- 2.1, 7.0 +/- 3.3, and 17.9 +/- 6.2%). TRPV1((-/-)) mice exhibited no changes in MAP in response to capsaicin, suggesting the actions of this agonist are specific to TRPV1 activation. Immunoblot analysis revealed decreased aortic TRPV1 protein expression in db/db compared with control mice. Capsaicin-induced responses were recorded following inhibition of endothelin A and B receptors (ET(A) /ET(B)). Inhibition of ET(A) receptors abolished the capsaicin-mediated increases in MAP. Combined antagonism of ET(A) and ET(B) receptors did not further inhibit the capsaicin response. Cultured endothelial cell exposure to capsaicin increased endothelin production as shown by an endothelin ELISA assay, which was attenuated by inhibition of TRPV1 or endothelin-converting enzyme. TRPV1 channels contribute to the regulation of vascular reactivity and MAP via production of endothelin and subsequent activation of vascular ET(A) receptors. Impairment of TRPV1 channel function may contribute to vascular dysfunction in diabetes.
Ohanyan Vahagn A; Guarini Giacinta; Thodeti Charles K; Talasila Phani K; Raman Priya; Haney Rebecca M; Meszaros J Gary; Damron Derek S; Bratz Ian N
American journal of physiology. Heart and circulatory physiology
2011
2011-09
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/ajpheart.00082.2011" target="_blank" rel="noreferrer noopener">10.1152/ajpheart.00082.2011</a>
PKCalpha mediates acetylcholine-induced activation of TRPV4-dependent calcium influx in endothelial cells.
Acetylcholine/*pharmacology; Animals; Calcium Signaling/*drug effects; Carbazoles/pharmacology; Cells; Cultured; Endothelial Cells/*drug effects/enzymology; Enzyme Activation; Inbred C57BL; Knockout; Male; Mesenteric Arteries/drug effects/enzymology; Mice; Mutation; Nitric Oxide Synthase Type III/metabolism; Phosphorylation; Protein Kinase C-alpha/genetics/*metabolism; Protein Kinase Inhibitors/pharmacology; Tetradecanoylphorbol Acetate/pharmacology; Time Factors; Transfection; TRPV Cation Channels/*agonists/deficiency/genetics/metabolism; Vasodilation/*drug effects; Vasodilator Agents/*pharmacology
Transient receptor potential vanilloid channel 4 (TRPV4) is a polymodally activated nonselective cationic channel implicated in the regulation of vasodilation and hypertension. We and others have recently shown that cyclic stretch and shear stress activate TRPV4-mediated calcium influx in endothelial cells (EC). In addition to the mechanical forces, acetylcholine (ACh) was shown to activate TRPV4-mediated calcium influx in endothelial cells, which is important for nitric oxide-dependent vasodilation. However, the molecular mechanism through which ACh activates TRPV4 is not known. Here, we show that ACh-induced calcium influx and endothelial nitric oxide synthase (eNOS) phosphorylation but not calcium release from intracellular stores is inhibited by a specific TRPV4 antagonist, AB-159908. Importantly, activation of store-operated calcium influx was not altered in the TRPV4 null EC, suggesting that
Adapala Ravi K; Talasila Phani K; Bratz Ian N; Zhang David X; Suzuki Makoto; Meszaros J Gary; Thodeti Charles K
American journal of physiology. Heart and circulatory physiology
2011
2011-09
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/ajpheart.00142.2011" target="_blank" rel="noreferrer noopener">10.1152/ajpheart.00142.2011</a>
Propofol causes vasodilation in vivo via TRPA1 ion channels: role of nitric oxide and BKCa channels.
Female; Male; Animals; Mice; Signal Transduction; TRPA1 Cation Channel; Arterial Pressure/drug effects; Vasodilator Agents/*pharmacology; Propofol/*pharmacology; Transient Receptor Potential Channels/genetics/*metabolism; Large-Conductance Calcium-Activated Potassium Channel alpha Subunits/*physiology; Nitric Oxide/*physiology; TRPV Cation Channels/genetics/metabolism; Inbred C57BL; Knockout; Drug Evaluation; Preclinical
BACKGROUND: Transient receptor potential (TRP) ion channels of the A1 (TRPA1) and V1 (TRPV1) subtypes are key regulators of vasomotor tone. Propofol is an intravenous anesthetic known to cause vasorelaxation. Our objectives were to examine the extent to which TRPA1 and/or TRPV1 ion channels mediate propofol-induced depressor responses in vivo and to delineate the signaling pathway(s) involved. METHODS: Mice were subjected to surgery under 1.5-2.5% sevoflurane gas with supplemental oxygen. After a stable baseline in mean arterial pressure (MAP) was achieved propofol (2.5, 5.0, 10.0 mg/kg/min) was administered to assess the hemodynamic actions of the intravenous anesthetic. The effect of nitric oxide synthase (NOS) inhibition with L-NAME and/or calcium-gated K+ channel (BKCa) inhibition with Penetrim A (Pen A), alone and in combination, on propofol-induced decreases in mean arterial pressure were assessed in control C57Bl/6J, TRPA1-/-, TRPV1-/- and double-knockout mice (TRPAV-/-). RESULTS: Propofol decreased MAP in control mice and this effect was markedly attenuated in
Sinha Sayantani; Sinharoy Pritam; Bratz Ian N; Damron Derek S
PloS one
2015
1905-07
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1371/journal.pone.0122189" target="_blank" rel="noreferrer noopener">10.1371/journal.pone.0122189</a>
Propofol restores transient receptor potential vanilloid receptor subtype-1 sensitivity via activation of transient receptor potential ankyrin receptor subtype-1 in sensory neurons.
Male; Mice; Capsaicin; Cells; Anesthetics; Animal Studies; Genes – Drug Effects; Carrier Proteins – Drug Effects; Carrier Proteins – Metabolism; Intravenous – Pharmacodynamics; Propofol – Pharmacodynamics; Sensory Receptor Cells – Drug Effects
Background: Cross talk between peripheral nociceptors belonging to the transient receptor potential vanilloid receptor subtype-1 (TRPV1) and ankyrin subtype-1 (TRPA1) family has been demonstrated recently. Moreover, the intravenous anesthetic propofol has directly activates TRPA1 receptors and indirectly restores sensitivity of TRPV1 receptors in dorsal root ganglion (DRG) sensory neurons. Our objective was to determine the extent to which TRPA1 activation is involved in mediating the propofol-induced restoration of TRPV1 sensitivity.Methods: Mouse DRG neurons were isolated by enzymatic dissociation and grown for 24 h. F-11 cells were transfected with complementary DNA for both TRPV1 and TRPA1 or TRPV1 only. The intracellular Ca concentration was measured in individual cells via fluorescence microscopy. After TRPV1 desensitization with capsaicin (100 nM), cells were treated with propofol (1, 5, and 10 μM) alone or with propofol in the presence of the TRPA1 antagonist, HC-030031 (0.5 μM), or the TRPA1 agonist, allyl isothiocyanate (AITC; 100 μM); capsaicin was then reapplied.Results: In DRG neurons that contain both TRPV1 and TRPA1, propofol and AITC restored TRPV1 sensitivity. However, in DRG neurons containing only TRPV1 receptors, exposure to propofol or AITC after desensitization did not restore capsaicin-induced TRPV1 sensitivity. Similarly, in F-11 cells transfected with both TRPV1 and TRPA1, propofol and AITC restored TRPV1 sensitivity. However, in F-11 cells transfected with TRPV1 only, neither propofol nor AITC was capable of restoring TRPV1 sensitivity.Conclusions: These data demonstrate that propofol restores TRPV1 sensitivity in primary DRG neurons and in cultured F-11 cells transfected with both the TRPV1 and TRPA1 receptors via a TRPA1-dependent process. Propofol's effects on sensory neurons may be clinically important and may contribute to peripheral sensitization to nociceptive stimuli in traumatized tissue.
Zhang H; Wickley PJ; Sinha S; Bratz IN; Damron DS; Zhang Hongyu; Wickley Peter J; Sinha Sayantani; Bratz Ian N; Damron Derek S
Anesthesiology
2011
2011-05
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1097/ALN.0b013e31820dee67" target="_blank" rel="noreferrer noopener">10.1097/ALN.0b013e31820dee67</a>
Propofol restores TRPV1 sensitivity via a TRPA1-, nitric oxide synthase-dependent activation of PKCepsilon.
PKCepsilon and NOS; propofol; TRPA1; TRPV1
We previously demonstrated that the intravenous anesthetic, propofol, restores the sensitivity of transient receptor potential vanilloid channel subtype-1 (TRPV1) receptors via a protein kinase C epsilon (PKCepsilon)-dependent and transient receptor potential ankyrin channel subtype-1 (TRPA1)-dependent pathway in sensory neurons. The extent to which the two pathways are directly linked or operating in parallel has not been determined. Using a molecular approach, our objectives of the current study were to confirm that TRPA1 activation directly results in PKCepsilon activation and to elucidate the cellular mechanism by which this occurs. F-11 cells were transfected with complimentary DNA (cDNA) for TRPV1 only or both TRPV1 and TRPA1. Intracellular Ca(2+) concentration was measured in individual cells via fluorescence microscopy. An immunoblot analysis of the total and phosphorylated forms of PKCepsilon, nitric oxide synthase (nNOS), and TRPV1 was also performed. In F-11 cells containing both channels, PKCepsilon inhibition prevented the propofol- and allyl isothiocyanate (AITC)-induced restoration of TRPV1 sensitivity to agonist stimulation as well as increased phosphorylation of PKCepsilon and TRPV1. In cells containing TRPV1 only, neither agonist induced PKCepsilon or TRPV1 phosphorylation. Moreover, NOS inhibition blocked propofol-and AITC-induced restoration of TRPV1 sensitivity and PKCepsilon phosphorylation, and PKCepsilon inhibition prevented the nitric oxide donor, SNAP, from restoring TRPV1 sensitivity. Also, propofol-and AITC-induced phosphorylation of nNOS and nitric oxide (NO) production were blocked with the
Sinharoy Pritam; Zhang Hongyu; Sinha Sayantani; Prudner Bethany C; Bratz Ian N; Damron Derek S
Pharmacology research & perspectives
2015
2015-08
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1002/prp2.153" target="_blank" rel="noreferrer noopener">10.1002/prp2.153</a>
TRPA1 and TRPV1 contribute to propofol-mediated antagonism of U46619-induced constriction in murine coronary arteries.
Male; Animals; Mice; TRPV Cation Channels/genetics/*metabolism; TRPA1 Cation Channel; Endothelial Cells/drug effects/metabolism; Nitric Oxide Synthase Type III/metabolism; Vasodilator Agents/*pharmacology; Coronary Vessels/*drug effects/metabolism; Large-Conductance Calcium-Activated Potassium Channel alpha Subunits/metabolism; Microvessels/drug effects/metabolism; Propofol/*pharmacology; Transient Receptor Potential Channels/genetics/*metabolism; Vasoconstrictor Agents/antagonists & inhibitors/pharmacology; Vasodilation/drug effects/physiology; Cells; Cultured; Inbred C57BL; Knockout; 15-Hydroxy-11 alpha; 9 alpha-(epoxymethano)prosta-5; 13-dienoic Acid/*antagonists & inhibitors/pharmacology
BACKGROUND: Transient receptor potential (TRP) ion channels have emerged as key components contributing to vasoreactivity. Propofol, an anesthetic is associated with adverse side effects including hypotension and acute pain upon infusion. Our objective was to determine the extent to which TRPA1 and/or TRPV1 ion channels are involved in mediating propofol-induced vasorelaxation of mouse coronary arterioles in vitro and elucidate the potential cellular signal transduction pathway by which this occurs. METHODS: Hearts were excised from anesthetized mice and coronary arterioles were dissected from control C57Bl/6J, TRPA1-/-, TRPV1-/- and double-knockout mice (TRPAV-/-). Isolated microvessels were cannulated and secured in a temperature-controlled chamber and allowed to equilibrate for 1 hr. Vasoreactivity studies were performed in microvessels pre-constricted with U46619 to assess the dose-dependent relaxation effects of propofol on coronary microvascular tone. RESULTS: Propofol-induced relaxation was unaffected in vessels obtained from TRPV1-/- mice, markedly attenuated in pre-constricted vessels obtained from TRPA1-/- mice and abolished in vessels obtained from
Sinharoy Pritam; Bratz Ian N; Sinha Sayantani; Showalter Loral E; Andrei Spencer R; Damron Derek S
PloS one
2017
2017
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1371/journal.pone.0180106" target="_blank" rel="noreferrer noopener">10.1371/journal.pone.0180106</a>
TRPA1 ion channel stimulation enhances cardiomyocyte contractile function via a CaMKII-dependent pathway.
[Ca2+]i; *Myocardial Contraction; Animals; Calcium-Calmodulin-Dependent Protein Kinase Type 2/*metabolism; CaMKII; Cardiac/*metabolism; cardiomyocytes; contractility; Inbred C57BL; Knockout; Mice; Myocytes; TRPA1; TRPA1 Cation Channel/deficiency/*metabolism
RATIONALE: Transient receptor potential channels of the ankyrin subtype-1 (TRPA1) are non-selective cation channels that show high permeability to calcium. Previous studies from our laboratory have demonstrated that TRPA1 ion channels are expressed in adult mouse ventricular cardiomyocytes (CMs) and are localized at the z-disk, costamere and intercalated disk. The functional significance of TRPA1 ion channels in the modulation of CM contractile function have not been explored. OBJECTIVE: To identify the extent to which TRPA1 ion channels are involved in modulating CM contractile function and elucidate the cellular mechanism of action. METHODS AND RESULTS: Freshly isolated CMs were obtained from murine heart and loaded with Fura-2 AM. Simultaneous measurement of intracellular free Ca(2+) concentration ([Ca(2+)]i) and contractility was performed in individual CMs paced at 0.3 Hz. Our findings demonstrate that TRPA1 stimulation with AITC results in a dose-dependent increase in peak [Ca(2+)]i and a concomitant increase in CM fractional shortening. Further analysis revealed a dose-dependent acceleration in time to peak [Ca(2+)]i and velocity of shortening as well as an acceleration in [Ca(2+)]i decay and velocity of relengthening. These effects of TRPA1 stimulation were not observed in CMs pre-treated with the TRPA1 antagonist, HC-030031 (10 micromol/L) nor in CMs obtained from TRPA1(-/-) mice. Moreover, we observed no significant increase in cAMP levels or PKA activity in response to TRPA1 stimulation and the PKA inhibitor peptide (PKI
Andrei Spencer R; Ghosh Monica; Sinharoy Pritam; Dey Souvik; Bratz Ian N; Damron Derek S
Channels (Austin, Tex.)
2017
2017-11
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1080/19336950.2017.1365206" target="_blank" rel="noreferrer noopener">10.1080/19336950.2017.1365206</a>
TRPA1 is functionally co-expressed with TRPV1 in cardiac muscle: Co-localization at z-discs, costameres and intercalated discs.
Animals; Ca2+; Calcium/physiology; Cardiac/*physiology; cardiomyocytes; Inbred C57BL; Male; Mice; Myocytes; Transient Receptor Potential Channels/genetics/*physiology; TRPA1; TRPA1 Cation Channel; TRPV Cation Channels/genetics/*physiology; TRPV1; Z-disc
Transient receptor potential channels of the ankyrin subtype-1 (TRPA1) and vanilloid subtype-1 (TRPV1) are structurally related, non-selective cation channels that show a high permeability to calcium. Previous studies indicate that TRP channels play a prominent role in the regulation of cardiovascular dynamics and homeostasis, but also contribute to the pathophysiology of many diseases and disorders within the cardiovascular system. However, no studies to date have identified the functional expression and/or intracellular localization of TRPA1 in primary adult mouse ventricular cardiomyocytes (CMs). Although TRPV1 has been implicated in the regulation of cardiac function, there is a paucity of information regarding functional expression and localization of TRPV1 in adult CMs. Our current studies demonstrate that TRPA1 and TRPV1 ion channels are co-expressed at the protein level in CMs and both channels are expressed throughout the endocardium, myocardium and epicardium. Moreover, immunocytochemical localization demonstrates that both channels predominantly colocalize at the Z-discs, costameres and intercalated discs. Furthermore, specific TRPA1 and TRPV1 agonists elicit dose-dependent, transient rises in intracellular free calcium concentration ([Ca(2+)]i) that are abolished in CMs obtained from TRPA1(-/-) and TRPV1(-/-) mice. Similarly, we observed a dose-dependent attenuation of the TRPA1 and TRPV1 agonist-induced increase in [Ca(2+)]i when WT CMs were pretreated with increasing concentrations of selective TRPA1 or TRPV1 channel antagonists. In summary, these findings demonstrate functional expression and the precise ultrastructural localization of TRPA1 and TRPV1 ion channels in freshly isolated mouse CMs. Crosstalk between TRPA1 and TRPV1 may be important in mediating cellular signaling events in cardiac muscle.
Andrei Spencer R; Sinharoy Pritam; Bratz Ian N; Damron Derek S
Channels (Austin, Tex.)
2016
2016-09
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1080/19336950.2016.1185579" target="_blank" rel="noreferrer noopener">10.1080/19336950.2016.1185579</a>