Neuropeptide Y induced increase of cytosolic and nuclear Ca2+ in heart and vascular smooth muscle cells

It was reported that neuropeptide Y (NPY) affects cardiac and vascular smooth muscle (VSM) function probably by increasing intracellular Ca2+. In this study, using fura-2 microfluorometry and fluo-3 confocal microscopy techniques for intracellular Ca2+ measurement, we attempted to verify whether the action of NPY receptor's stimulation in heart and VSM cells modulates intracellular Ca2+ and whether this effect is mediated via the Y1 receptor type. Using spontaneously contracting single ventricular heart cells of 10-day-old embryonic chicks and the fluo-3 confocal microscopy Ca2+ measurement technique to localize cytosolic ([Ca]c) and nuclear ([Ca]n) free Ca2+ level and distribution, 10-10 M of human (h) NPY significantly (P < 0.05) increased the frequency of cytosolic and nuclear Ca2+ transients during spontaneous contraction. Increasing the concentration of hNPY (10-9 M) did not further increase the frequency of Ca2+ transients. The L-type Ca2+ channel blocker, nifedipine (10-5 M), significantly (P < 0.001) blocked the spontaneous rise of intracellular Ca2+ in the absence and presence of hNPY (10-10 and 10-9 M). However, the selective Y1 receptor antagonist, BIBP3226 (10-6 M), significantly decreased the hNPY-induced (10-10 and 10-9 M) increase in the frequency of Ca2+ transients back to near the control level (P < 0.05). In resting nonworking heart and human aortic VSM cells, hNPY induced a dose-dependent sustained increase of basal resting intracellular Ca2+ with an EC50 near 10-9 M. This sustained increase was cytosolic and nuclear and was completely blocked by the Ca2+ chelator EGTA, and was significantly decreased by the Y1 receptor antagonist BIBP3226 in both heart (P < 0.05) and VSM (P < 0.01) cells. These results strongly suggest that NPY stimulates the resting basal steady-state Ca2+ influx through the sarcolemma and induces sustained increases of cytosolic and nuclear calcium, in good part, via the activation of the sarcolemma membrane Y1 receptor type in both resting heart and VSM cells. In addition, NPY also increased the frequency of Ca2+ transients during spontaneous contraction of heart cells mainly via the activation of the Y1 receptor type, which may explain in part the active cardiovascular action of this peptide.Key words: heart, vascular smooth muscle, neuropeptide Y, BIBP3226, calcium, nucleus.

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Neuropeptide Y (NPY) and NPY receptors in the cardiovascular system: implication in the regulation of intracellular calciumThis paper is one of a selection of papers published in this Special Issue, entitled Young Investigators' Forum.

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y06-106 ◽

2007 ◽

Vol 85 (1) ◽

pp. 43-53 ◽

Cited By ~ 28

Author(s):

Danielle Jacques ◽

Dima Abdel-Samad

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Neuropeptide Y ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Cell Types ◽

Heart Cells ◽

Microscopy Technique ◽

Intracellular Ca

The 3-dimensional confocal microscopy technique has allowed us to identify the presence of yet another cardioactive factor and its receptor, namely neuropeptide Y (NPY) and its Y1 receptor, at the level of vascular smooth muscle cells and heart cells including endocardial endothelial cells (EECs). Using this technique, we also demonstrated that NPY is able to induce an increase in both cytosolic and nuclear calcium in all these cell types. Furthermore, besides being expressed at the level of EECs, NPY is also released from these cells following a sustained increase of intracellular Ca2+. This suggests the ability of NPY to contribute to the regulation of the excitation–secretion coupling of EECs and the excitation–contraction coupling of cardiomyocytes and vascular smooth muscle cells.

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Nonpeptidic antagonists of ETA and ETB receptors reverse the ET-1-induced sustained increase of cytosolic and nuclear calcium in human aortic vascular smooth muscle cellsThis article is one of a selection of papers published in the special issue (part 2 of 2) on Forefronts in Endothelin.

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y08-048 ◽

2008 ◽

Vol 86 (8) ◽

pp. 546-556 ◽

Cited By ~ 14

Author(s):

Ghassan Bkaily ◽

Sanaa Choufani ◽

Levon Avedanian ◽

Lena Ahmarani ◽

Moni Nader ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Receptor Antagonist ◽

G Protein ◽

Calcium Influx ◽

Receptor Activation ◽

3 Dimensional ◽

Intracellular Ca ◽

Selection Of ◽

Sustained Increase

Our previous work showed that ET-1 induced a concentration-dependent increase of cytosolic Ca2+ ([Ca]c) and nuclear Ca2+ ([Ca]n) in human aortic vascular smooth muscle cells (hVSMCs). In the present study, using hVSMCs and 3-dimensional confocal microscopy coupled to the Ca2+ fluorescent probe Fluo-3, we showed that peptidic antagonists of ETA and ETB receptors (BQ-123 (10−6 mol/L) and BQ-788 (10−7 mol/L), respectively) prevented, but did not reverse, ET-1-induced sustained increase of [Ca]c and [Ca]n. In contrast, nonpeptidic antagonists of ETA and ETB (respectively, BMS-182874 (10−8–10−6 mol/L) and A-192621 (10−7 mol/L)) both prevented and reversed ET-1-induced sustained increase of [Ca]c and [Ca]n. Furthermore, activation of the ETB receptor alone using the specific agonist IRL-1620 (10−9 mol/L) induced sustained increases of [Ca]c and [Ca]n, and subsequent administration of ET-1 (10−7 mol/L) further increased nuclear Ca2+. ET-1-induced increase of [Ca]c and [Ca]n was completely blocked by extracellular application of the Ca2+ chelator EGTA. Pretreatment with the G protein inhibitors pertussis toxin (PTX) and cholera toxin (CTX) also prevented the ET-1 response; however, strong membrane depolarization with KCl (30 mmol/L) subsequently induced sustained increase of [Ca]c and [Ca]n. Pretreatment of hVSMCs with either the PKC activator phorbol-12,13-dibutyrate or the PKC inhibitor bisindolylmaleimide did not affect ET-1-induced sustained increase of intracellular Ca2+. These results suggest that both ETA- and ETB-receptor activation contribute to ET-1-induced sustained increase of [Ca]c and [Ca]n in hVSMCs. Moreover, in contrast to the peptidic antagonists of ET-1 receptors, the nonpeptidic ETA-receptor antagonist BMS-182874 and the nonpeptidic ETB-receptor antagonist A-192621 were able to reverse the effect of ET-1. Nonpeptidic ETA- and ETB-receptor antagonists may therefore be better pharmacological tools for blocking ET-1-induced sustained increase of intracellular Ca2+ in hVSMCs. Our results also suggest that the ET-1-induced sustained increase of [Ca]c and [Ca]n is not mediated via activation of PKC, but via a PTX- and CTX-sensitive G protein calcium influx through the R-type Ca2+ channel.

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Growth-dependent alterations of intracellular Ca(2+)-handling mechanisms of vascular smooth muscle cells. PDGF negatively regulates functional expression of voltage-dependent, IP3-mediated, and CA(2+)-induced Ca2+ release channels.

Circulation Research ◽

10.1161/01.res.69.5.1327 ◽

1991 ◽

Vol 69 (5) ◽

pp. 1327-1339 ◽

Cited By ~ 24

Author(s):

M Masuo ◽

T Toyo-oka ◽

W S Shin ◽

T Sugimoto

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Functional Expression ◽

Voltage Dependent ◽

Intracellular Ca

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Ets-1 is an early response gene activated by ET-1 and PDGF-BB in vascular smooth muscle cells

AJP Cell Physiology ◽

10.1152/ajpcell.1998.274.2.c472 ◽

1998 ◽

Vol 274 (2) ◽

pp. C472-C480 ◽

Cited By ~ 83

Author(s):

Shinji Naito ◽

Shunichi Shimizu ◽

Shigeto Maeda ◽

Jianwei Wang ◽

Richard Paul ◽

...

Keyword(s):

Gene Expression ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Inositol Phosphate ◽

Muscle Cells ◽

Tetraacetic Acid ◽

Acetoxymethyl Ester ◽

Intracellular Ca

Ets-1 is a transcription factor that activates expression of matrix-degrading proteinases such as collagenase and stromelysin. To study the control of ets-1 gene expression in rat vascular smooth muscle cells (VSMC), cells were exposed to factors known to regulate VSMC migration and proliferation. Platelet-derived growth factor-BB (PDGF-BB), endothelin-1 (ET-1), and phorbol 12-myristate 13-acetate (PMA) induced a dose-dependent expression of ets-1 mRNA. These effects were abrogated by inhibition of protein kinase C (PKC) by H-7 or chronic PMA treatment. Ets-1 mRNA was superinduced by PDGF-BB and ET-1 in the presence of cycloheximide. The chelation of intracellular Ca2+ by 1,2-bis(2-aminophenoxy)ethane- N, N, N′, N′-tetraacetic acid-acetoxymethyl ester and the depletion of endoplasmic reticulum intracellular Ca2+concentration ([Ca2+]i) by thapsigargin inhibited PDGF-BB- and ET-1-induced ets-1 mRNA, whereas ethylene glycol-bis(β-aminoethyl ether)- N, N, N′, N′-tetraacetic acid had no effect. However, [Ca2+]irelease alone was not sufficient to increase ets-1 mRNA. Forskolin blocked ET-1-, PDGF-BB-, and PMA-induced ets-1 mRNA, as well as inositol phosphate formation, consistent with an effect through impairment of PKC activation. Inhibitors of ets-1 gene expression, such as H-7 and herbimycin A, inhibited the ET-1 induction of collagenase I mRNA. We propose that ets-1 may be an important element in the orchestration of matrix proteinase expression and of vascular remodeling after arterial injury.

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The Apoptotic Effect of Angiotensin II in Human Vascular Smooth Muscle Cells

Microscopy and Microanalysis ◽

10.1017/s1431927600035674 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 636-637

Author(s):

E. Ou ◽

C. Wei

Keyword(s):

Smooth Muscle ◽

Angiotensin Ii ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Receptor Antagonist ◽

Vascular Smooth Muscle Cells ◽

Artery Bypass ◽

Muscle Cells ◽

Tunel Staining ◽

Apoptotic Effect

Angiotensin II is a potent vasoconstrictor and mitogenic factor. However, the effects of angiotensin II on human vascular smooth muscle cells apoptosis remain controversial. Therefore, the current study was designed to investigate the actions of angiotensin II on human vascular smooth muscle cells apoptosis.Human saphenous vein was obtained from coronary artery bypass surgery (n=6) and was minced and incubated in the special tissue culture system in the absence or presence of angiotensin II (10-6 to 10-12M) for 1, 2, 4, 8, 16, & 24 hours. These studies were repeated with losartan (10-6M, AT- 1 receptor antagonist) and PD-123319 (10-6M, AT-2 receptor antagonist). To detect the DNA fragmentation, in situ terminal deoxymucleotidyl transferase dUTP nick end labeling (TUNEL) and DNA agarose gel analyses were performed. An average of 1000 nuclei was analyzed for TUNEL studies.TUNEL staining and DNA gel analysis demonstrated that angiotensin II increased apoptosis in human vascular smooth muscle cells.

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Evidence against the role of α1-adrenoceptor reserve in buffering the inhibitory effect of nifedipine on the contractility of canine vascular smooth muscle

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y90-203 ◽

1990 ◽

Vol 68 (10) ◽

pp. 1346-1350 ◽

Cited By ~ 3

Author(s):

Yong-Yuan Guan ◽

Chiu-Yin Kwan ◽

Edwin E. Daniel

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Saphenous Vein ◽

Mesenteric Artery ◽

Inhibitory Effect ◽

Contractile Responses ◽

Intracellular Ca ◽

Adrenoceptor Agonists ◽

The Difference ◽

Muscle Calcium

The relationship between the postsynaptic α1-adrenoceptor reserve and the sensitivity of vasoconstriction induced by α-adrenoceptor agonists to the dihydropyridine Ca2+ entry blocker nifedipine was investigated in isolated muscle strips of dog mesenteric artery (DMA) and saphenous vein (DSV). The amplitudes of the contractile responses of DMA induced by phenylephrine were the same as those in DSV in the presence and in the absence of extracellular Ca2+. The use of 3 × 10−9 M phenoxybenzamine to irreversibly block the α1-adrenoceptors revealed a marked difference in the size of the α1-adrenoceptor reserve between DMA (40%) and DSV (7%). In spite of a larger receptor reserve, the contractile responses induced by phenylephrine in DMA were more sensitive to nifedipine compared with those in DSV. These results suggest that the postsynaptic α1-adrenoceptor reserve in vascular smooth muscle, at least in DMA and DSV, does not play an important role in buffering the inhibitory effect of nifedipine on the contractile response to a full agonist of α1-adrenoceptors. Other factors, such as the difference in the membrane depolarizing effect, the ability to utilize intracellular Ca2+ for contraction, and the possible existence of α1-adrenoceptor subtypes, may contribute to the different inhibitory effects of nifedipine on these blood vessels.Key words: adrenoceptors, nifedipine, smooth muscle, calcium, saphenous vein, mesenteric artery.

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Neuropeptide Y stimulates DNA synthesis in human vascular smooth muscle cells through neuropeptide Y Y1 receptors

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-78-3-256 ◽

2000 ◽

Vol 78 (3) ◽

pp. 256-259 ◽

Cited By ~ 6

Author(s):

T. Nilsson ◽

L. Edvinsson

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Dna Synthesis ◽

Neuropeptide Y ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells

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Neuropeptide Y induced increase of cytosolic and nuclear Ca2+ in heart and vascular smooth muscle cells

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-78-2-162 ◽

2000 ◽

Vol 78 (2) ◽

pp. 162-172 ◽

Cited By ~ 20

Author(s):

Danielle Jacques ◽

Sawsan Sader ◽

Nesrine El-Bizri ◽

Sanaa Chouffani ◽

Ghada Hassan ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Neuropeptide Y ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells

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Hypotonic swelling-induced Ca2+ release by an IP3-insensitive Ca2+ store

AJP Cell Physiology ◽

10.1152/ajpcell.2001.281.2.c555 ◽

2001 ◽

Vol 281 (2) ◽

pp. C555-C562 ◽

Cited By ~ 9

Author(s):

Madhumita Jena Mohanty ◽

Maian Ye ◽

Xingli Li ◽

Noreen F. Rossi

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Nicotinic Acid ◽

Vascular Smooth Muscle Cells ◽

Ruthenium Red ◽

A7r5 Cells ◽

Inositol 1,4,5 Trisphosphate ◽

Intracellular Ca ◽

Hypotonic Swelling

Hypotonic swelling increases the intracellular Ca2+ concentration ([Ca2+]i) in vascular smooth muscle cells (VSMC). The source of this Ca2+ is not clear. To study the source of increase in [Ca2+]i in response to hypotonic swelling, we measured [Ca2+]i in fura 2-loaded cultured VSMC (A7r5 cells). Hypotonic swelling produced a 40.7-nM increase in [Ca2+]i that was not inhibited by EGTA but was inhibited by 1 μM thapsigargin. Prior depletion of inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ stores with vasopressin did not inhibit the increase in [Ca2+]i in response to hypotonic swelling. Exposure of 45Ca2+-loaded intracellular stores to hypotonic swelling in permeabilized VSMC produced an increase in45Ca2+ efflux, which was inhibited by 1 μM thapsigargin but not by 50 μg/ml heparin, 50 μM ruthenium red, or 25 μM thio-NADP. Thus hypotonic swelling of VSMC causes a release of Ca2+ from the intracellular stores from a novel site distinct from the IP3-, ryanodine-, and nicotinic acid adenine dinucleotide phosphate-sensitive stores.

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