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Lee H, Jun DJ, Suh BC, Choi BH, Lee JH, Do MS, Suh BS, Ha H, Kim KT. Dual roles of P2 purinergic receptors in insulin-stimulated leptin production and lipolysis in differentiated rat white adipocytes. J Biol Chem 2005; 280:28556-63. [PMID: 15955812 DOI: 10.1074/jbc.m411253200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATP is co-localized with norepinephrine at the sympathetic nerve terminals and may be released simultaneously upon neuronal stimulation, which results in activation of purinergic receptors. To examine whether leptin synthesis and lipolysis are influenced by P2 purinergic receptor activation, the effects of ATP and other nucleotides on leptin secretion and glycerol release have been investigated in differentiated rat white adipocytes. Firstly, insulin-induced leptin secretion was inhibited by nucleotide treatment with the following efficacy order: 3'-O-(4-benzoyl)benzoyl ATP (BzATP) > ATP >> UTP. Secondly, treatment of adipocytes with ATP increased both intracellular Ca(2+) concentration and cAMP content. Intracellular calcium concentration was increased by ATP and UTP, but not BzATP, an effect attributed to phospholipase C-coupled P2Y(2). On the other hand, cAMP was generated by treatment with BzATP and ATPgammaS, but not UTP, indicating functional expression of adenylyl cyclase-coupled P2Y(11) receptors in white adipocytes. Thirdly, lipolysis was significantly activated by BzATP and ATP, which correlated with the characteristics of the P2Y(11) subtype. Taken together, the data presented here suggest that white adipocytes express at least two different types of P2Y receptors and that activation of P2Y(11) receptor might be involved in inhibition of leptin production and stimulation of lipolysis, suggesting that purinergic transmission can play an important role in white adipocyte physiology.
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Affiliation(s)
- Hyun Lee
- Department of Life Science, Pohang University of Science and Technology, Pohang 790-784, Korea
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Burnstock G, Knight GE. Cellular Distribution and Functions of P2 Receptor Subtypes in Different Systems. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 240:31-304. [PMID: 15548415 DOI: 10.1016/s0074-7696(04)40002-3] [Citation(s) in RCA: 573] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review is aimed at providing readers with a comprehensive reference article about the distribution and function of P2 receptors in all the organs, tissues, and cells in the body. Each section provides an account of the early history of purinergic signaling in the organ?cell up to 1994, then summarizes subsequent evidence for the presence of P2X and P2Y receptor subtype mRNA and proteins as well as functional data, all fully referenced. A section is included describing the plasticity of expression of P2 receptors during development and aging as well as in various pathophysiological conditions. Finally, there is some discussion of possible future developments in the purinergic signaling field.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Institute, Royal Free and University College Medical School, London NW3 2PF, United Kingdom
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Park DW, Cho T, Kim MR, Kim YA, Min CK, Hwang KJ. ATP-induced apoptosis of human granulosa luteal cells cultured in vitro. Fertil Steril 2003; 80:993-1002. [PMID: 14556823 DOI: 10.1016/s0015-0282(03)01118-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To investigate the role of extracellular adenosine triphosphatase (ATP) as an inducer of apoptotic cell death in human granulosa cells and to elucidate its underlying mechanism. DESIGN Prospective study. SETTING Gynecologic clinic and human reproduction research laboratory. PATIENT(S) Twenty-five patients undergoing IVF or IVF-ET. INTERVENTION(S) ATP treatment of granulosa luteal cells subjected to primary culture. MAIN OUTCOME MEASURE(S) Apoptosis was assessed by the annexin V binding assay and the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling assay. The receptor type that binds ATP, thus mediating ATP-induced apoptosis, was determined by using the calcium imaging and patch-clamp techniques. Mitochondrial depolarization was assessed by staining with the membrane potential-sensitive dye 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolyl carbocyanide iodide (JC-1). RESULT(S) ATP elevated [Ca(2+)](i) by mobilizing intracellularly stored Ca(2+). An ionic membrane current evoked by ATP was mediated by the Ca(2+)-activated K(+) channel. ATP induced a mitochondrial depolarization with a concomitant increase in cellular apoptosis. Treatment with hCG eliminated both ATP-induced mitochondrial depolarization and apoptosis. CONCLUSION(S) Extracellular ATP recognized by P(2Y) type purinoceptor triggers apoptosis in human granulosa luteal cells, and the downstream apoptotic cascade may act at least in part through mitochondria. The antiapoptotic effect of hCG has possible clinical implications in the treatment of disorders involving granulosa cell degeneration (such as follicular atresia).
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Affiliation(s)
- Dong-Wook Park
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
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Lee H, Choi BH, Suh BC, Lee SK, Kim KT. Attenuation of signal flow from P2Y6 receptor by protein kinase C-alpha in SK-N-BE(2)C human neuroblastoma cells. J Neurochem 2003; 85:1043-53. [PMID: 12716436 DOI: 10.1046/j.1471-4159.2003.01761.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Extracellular nucleotides exert a variety of biological actions through several kinds of P2 receptors in many tissues and cell types. We found that treatment with nucleotides increases intracellular Ca2+ concentration ([Ca2+]i) in SK-N-BE(2)C human neuroblastoma cells with a following order of potency: UDP > UTP > ADP >> ATP. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that specific mRNAs coding for human P2Y1, P2Y4, and P2Y6 receptors were expressed in the cells, but Northern blot analysis revealed that P2Y6 receptors were the predominant type. Activation of protein kinase C-alpha by treatment with 1 micro m phorbol 12-myristate 13-acetate dramatically inhibited both the UDP-induced [Ca2+]i rise and inositol 1,4,5-trisphosphate (IP3) generation, whereas incubation with pertussis toxin had little effect on the responses. The UDP-induced [Ca2+]i rise and IP3 production were maintained up to 30 min after stimulation, while bradykinin-induced responses rapidly decreased to the basal level within 5 min of stimulation. Pretreatment of cells with the maximal effective concentration of UDP reduced the subsequent carbachol- or bradykinin-induced [Ca2+]i rise without inhibition of IP3 generation. Neuronal differentiation of the cells by treatment with retinoic acid for 7 days did not change the expression level of P2Y6 receptors. Taken together, the data indicate that P2Y6 receptors highly responsive to diphosphonucleotide UDP are endogenously expressed in the human neuroblastoma SK-N-BE(2)C cells and that they are involved in the modulation of other phospholipase C-coupled receptor-mediated Ca2+ mobilization by depleting the IP3-sensitive Ca2+ stores.
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Affiliation(s)
- Hyun Lee
- Department of Life Science, Division of Molecular and Life Sciences, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784, Korea
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Suh BC, Kim TD, Lee JU, Seong JK, Kim KT. Pharmacological characterization of adenosine receptors in PGT-beta mouse pineal gland tumour cells. Br J Pharmacol 2001; 134:132-42. [PMID: 11522605 PMCID: PMC1572918 DOI: 10.1038/sj.bjp.0704218] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The adenosine receptor in mouse pinealocytes was identified and characterized using pharmacological and physiological approaches. 2. Expression of the two adenosine receptor subtypes A2B and A3 was detected in mouse pineal glands and PGT-beta cells by polymerase chain reaction and nucleotide sequencing. 3. Adenosine and 5'-N-ethylcarboxamidoadenosine (NECA) evoked cyclic AMP generation but the A2)-selective agonist 2-(4-(2-carboxyethyl)phenylethylamino)adenosine-5'-N-ethylcarboxamideadenosine (CGS 21680) and the A1-specific agonists R-N(6)-(2-phenylisopropyl)adenosine (R-PIA) and N(6)-cyclopentyladenosine (CPA) had little effect on intracellular cyclic AMP levels. The A2B receptor selective antagonists alloxazine and enprofylline completely blocked NECA-mediated cyclic AMP accumulation. 4. Treatment of cells with the A3-selective agonist N(6)-(3-iodobenzyl)-5'-(N-methylcarbamoyl)adenosine (IB-MECA) inhibited the elevation of the cyclic AMP level induced by NECA or isoproterenol in a concentration-dependent manner with maximal inhibition of 40 - 50%. These responses were blocked by the specific A3 adenosine receptor antagonist MRS 1191. Pretreatment of the cells with pertussis toxin attenuated the IB-MECA-induced responses, suggesting that this effect occurred via the pertussis toxin-sensitive inhibitory G proteins. 5. IB-MECA also caused a concentration-dependent elevation in [Ca(2+)]i and IP3 content. Both the responses induced by IB-MECA were attenuated by treatment with U73122 or phorbol 12-myristate 13-acetate. 6. These data suggest the presence of both A2B and A3 adenosine receptors in mouse pineal tumour cells and that the A2B receptor is positively coupled to adenylyl cyclase whereas the A3 receptor is negatively coupled to adenylyl cyclase and also coupled to phospholipase C.
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MESH Headings
- 4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone/pharmacology
- Adenosine/analogs & derivatives
- Adenosine/pharmacology
- Adenosine Triphosphate/pharmacology
- Adenosine-5'-(N-ethylcarboxamide)/pharmacology
- Adenylate Cyclase Toxin
- Adenylyl Cyclases/metabolism
- Animals
- Calcium/metabolism
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Dihydropyridines/pharmacology
- Dose-Response Relationship, Drug
- Enzyme Activation/drug effects
- Estrenes/pharmacology
- GTP-Binding Proteins/drug effects
- GTP-Binding Proteins/metabolism
- Gene Expression Regulation, Neoplastic/drug effects
- Inositol 1,4,5-Trisphosphate/metabolism
- Isoproterenol/pharmacology
- Mice
- Mice, Inbred CBA
- Pertussis Toxin
- Phospholipases/metabolism
- Pinealoma/metabolism
- Pinealoma/pathology
- Pyrrolidinones/pharmacology
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Adenosine A2B
- Receptor, Adenosine A3
- Receptors, Purinergic P1/drug effects
- Receptors, Purinergic P1/genetics
- Receptors, Purinergic P1/physiology
- Tetradecanoylphorbol Acetate/pharmacology
- Time Factors
- Tumor Cells, Cultured
- Virulence Factors, Bordetella/pharmacology
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Affiliation(s)
- Byung-Chang Suh
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784, Korea
| | - Tae-Don Kim
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784, Korea
| | - Jung-Uek Lee
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784, Korea
| | - Je-Kyung Seong
- Department of Laboratory Animal Medicine, Medical Research Center, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemun-gu, Seoul 120 – 752, Korea
| | - Kyong-Tai Kim
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, San 31, Hyoja-Dong, Pohang 790-784, Korea
- Author for correspondence:
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Suh BC, Kim JS, Namgung U, Han S, Kim KT. Selective inhibition of beta(2)-adrenergic receptor-mediated cAMP generation by activation of the P2Y(2) receptor in mouse pineal gland tumor cells. J Neurochem 2001; 77:1475-85. [PMID: 11413231 DOI: 10.1046/j.1471-4159.2001.00367.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Rhythmic noradrenergic signaling from the hypothalamic clock in the suprachiasmatic nucleus to the pineal gland causes an increase in intracellular cAMP which regulates the circadian fluctuation of melatonin synthesis. The activation of phospholipase C (PLC)-coupled P2Y(2) receptors upon treatment with ATP and UTP exclusively inhibited the isoproterenol-stimulated cAMP production in mouse pineal gland tumor cells. However, the activation of other PLC-coupled receptors including P2Y(1) and bombesin receptors had little or no effect on the isoproterenol-stimulated cAMP production. Also, ATP did not inhibit cAMP production caused by forskolin, prostaglandin E(2), or the adenosine analog NECA. These results suggest a selective coupling between signalings of P2Y(2) and beta(2)-adrenergic receptors. The binding of [(3)H]CGP12177 to beta(2)-adrenergic receptors was not effected by the presence of ATP or UTP. Ionomycin decreased the isoproterenol-stimulated cAMP production, whereas phorbol 12-myristate 13-acetate slightly potentiated the isoproterenol response. Chelation of intracellular Ca(2+), however, had little effect on the ATP-induced inhibition of cAMP production, while it completely reversed the ionomycin-induced inhibition. Treatment of cells with pertussis toxin almost completely blocked the inhibitory effect of nucleotides. Pertussis toxin also inhibited the nucleotide-induced increase in intracellular Ca(2+) and inositol 1,4,5-trisphosphate production by 30-40%, suggesting that the ATP-mediated inhibition of the cAMP generation and the partial activation of PLC are mediated by pertussis toxin-sensitive G(i)-protein. We conclude that one of the functions of P2Y(2) receptors on the pineal gland is the selective inhibition of beta-adrenergic receptor-mediated signaling pathways via the inhibitory G-proteins.
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Affiliation(s)
- B C Suh
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang, Korea
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Suh BC, Kim TD, Lee IS, Kim KT. Differential regulation of P2Y(11) receptor-mediated signalling to phospholipase C and adenylyl cyclase by protein kinase C in HL-60 promyelocytes. Br J Pharmacol 2000; 131:489-97. [PMID: 11015299 PMCID: PMC1572341 DOI: 10.1038/sj.bjp.0703581] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The regulatory mode of the P2Y(11) purinoceptor-mediated signalling cascades towards phospholipase C and adenylyl cyclase was studied in HL-60 promyelocytes. Treatment with the potent P2Y(11) receptor activator dATP evoked an elevated intracellular Ca(2+) concentration ([Ca(2+)](i)) and inositol 1,4,5-trisphosphate (IP(3)) production that was sustained for longer than 30 min. However, the dATP-induced responses were significantly inhibited by the activation of protein kinase C after a short exposure to phorbol 12-myristate 13-acetate (PMA). dATP also potently stimulated cyclic AMP production with half maximum effect seen at 23+/-7 microM dATP. In addition, a 5-min pretreatment with PMA enhanced the dATP-stimulated cyclic AMP accumulation. PMA potentiated the cyclic AMP production when adenylyl cyclase was activated directly by forskolin or indirectly by G protein activation after cholera toxin treatment. dATP also enhanced the forskolin-mediated cyclic AMP generation. Treatment of the cells with 10 microM U-73122, which almost completely blocked the dATP-stimulated IP(3) production and [Ca(2+)](i) rise, had no effect on cyclic AMP accumulation, while 10 microM 9-(tetrahydro-2-furyl)adenine (SQ 22536), which inhibited the adenylyl cyclase activation, did not effect the dATP-stimulated phosphoinositide turnover. Taken together, the results indicate that P2Y(11) receptor-mediated activation of phospholipase C and adenylyl cyclase occurs through independent pathways and is differentially regulated by protein kinase C in HL-60 cells.
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Affiliation(s)
- Byung-Chang Suh
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Tae-Don Kim
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Ihn-Soon Lee
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Kyong-Tai Kim
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
- Author for correspondence:
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Gutierrez AM, Lou X, Erik A, Persson G, Ring A. Ca2+ response of rat mesangial cells to ATP analogues. Eur J Pharmacol 1999; 369:107-12. [PMID: 10204688 DOI: 10.1016/s0014-2999(99)00032-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The aim of this investigation was to characterise the effects of ATP analogues and UTP on the single cell intracellular Ca2+ concentration ([Ca2+]i) in cultured rat mesangial cells. Typically, there were two phases in the Ca2+ response to the agonists, an initial fast transient peak and a subsequent slower decline, or plateau, phase. For the peak amplitude in [Ca2+]i the agonists had about equal effect. But when taking in consideration the percentage of responding cells and the integrated Ca2+ response over 1 min, the order of efficacy of nucleotide agonists (100 microM) was UTP = ATP > ATPgammaS > ADP = 2MeS-ATP (2-methylthio-ATP). Adenosine, AMP and beta,gamma-Me-ATP (100 microM) had no effect. Suramine (100 microM) and reactive blue (50 microM) decreased the number of responding cells. Removing Ca2+ from the bath diminished neither the peak in [Ca2+]i nor the percentage of responding cells, but the average [Ca2+]i increase in 1 min was significantly reduced. The results indicate that P2Y2 receptors are present in rat mesangial cells but it cannot be excluded that there are receptors distinct from P2Y2 which also mediate a rise in [Ca2+]i.
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Affiliation(s)
- A M Gutierrez
- Department of Physiology and Medical Biophysics, University of Uppsala, Sweden
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Suh BC, Chae HD, Chung JH, Kim KT. Pharmacological characterization of beta2-adrenoceptor in PGT-beta mouse pineal gland tumour cells. Br J Pharmacol 1999; 126:399-406. [PMID: 10077231 PMCID: PMC1565813 DOI: 10.1038/sj.bjp.0702248] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. The adrenoceptor in a mouse pineal gland tumour cell line (PGT-beta) was identified and characterized using pharmacological and physiological approaches. 2. Adrenaline and noradrenaline, adrenoceptor agonists, stimulated cyclic AMP generation in a concentration-dependent manner, but had no effect on inositol 1,4,5-trisphosphate production. Adrenaline was a more potent activator of cyclic AMP generation than noradrenaline, with half maximal-effective concentrations (EC50) seen at 175+/-22 nM and 18+/-2 microM for adrenaline and noradrenaline, respectively. 3. The addition of forskolin synergistically stimulated the adrenaline-mediated cyclic AMP generation in a concentration-dependent manner. 4. The pA2 value for the specific beta2-adrenoceptor antagonist ICI-118,551 (8.7+/-0.4) as an antagonist of the adrenaline-stimulated cyclic AMP generation were 3 units higher than the value for the betaI-adrenoceptor antagonist atenolol (5.6+/-0.3). 5. Treatment of the cells with adrenaline and forskolin evoked a 3 fold increase in the activity of serotonin N-acetyltransferase with the peak occurring 6 h after stimulation. 6. These results suggest the presence of beta2-adrenoceptors in mouse pineal cells and a functional relationship between the adenylyl cyclase system and the regulation of N-acetyltransferase expression.
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Affiliation(s)
- B C Suh
- Department of Life Science and Basic Science Research Institute, Pohang University of Science and Technology, Republic of Korea
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Balestrieri ML, Malik KU, Balestrieri C, Lee TC. Types of purinoceptors and phospholipase A2 involved in the activation of the platelet-activating factor-dependent transacetylase activity and arachidonate release by ATP in endothelial cells. Prostaglandins Other Lipid Mediat 1998; 56:363-75. [PMID: 9990678 DOI: 10.1016/s0090-6980(98)00065-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Acyl analogs of PAF are the major products synthesized during agonist stimulation of endothelial cells. We have previously shown that PAF: 1-acyl-2-lyso-sn-glycero-3-phosphocholine transacetylase in calf pulmonary artery endothelial cells is activated by ATP through protein phosphorylation, and the increase in transacetylase activity by ATP contributes to the biosynthesis of acyl analogs of PAF (J. Biol. Chem. 272, 17431-17437, 1997). To understand the mechanisms(s) by which ATP stimulates acyl analogs of PAF production, we have identified the subtypes of the purinergic receptor that are linked to the activation of two enzymes involved in the generation of acyl analogs of PAF, namely, transacetylase and phospholipase A2. Experiments with transient transfection of the cells with antisense and sense thio-oligonucleotide to cytosolic phospholipase A2 (cPLA2) were also performed to evaluate whether downstream activation of cPLA2 is involved in ATP-receptor mediated induction of arachidonate release and synthesis of radylacetyl-GPC. We found that the P2u/P2Y2 receptor, which recognizes a pyrimidine nucleotide, UTP, as well as purine nucleotides, shows a potency profile of UTP > ATP = ATP gamma S > 2-methylthio-ATP in mediating the activation of PAF: lysophospholipid transacetylase. On the other hand, ADP beta S and 2-methylthio-ATP have similar potencies as ATP but have lower potencies than UTP and ATP gamma S in stimulating the release of arachidonate. These results suggest that both P2u/P2Y2 and P2y/P2Y1 receptor subtypes promote arachidonate release. In addition, transient transfection of endothelial cells with cPLA2 antisense but not the sense thio-oligonucleotide inhibited the stimulation of arachidonate release and [3H]acetate incorporation into radyl[3H]acetyl-GPC. Thus, our data suggest that a receptor-mediated process is involved in the activation of transacetylase for the induced synthesis of acyl analogs of PAF in endothelial cells. Furthermore, it is likely that cPLA2 supplies the lysophospholipids as substrates for the transacetylation reaction.
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Affiliation(s)
- M L Balestrieri
- Environmental and Health Sciences Division, Oak Ridge Associated Universities, Tennessee 37831-0117, USA
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