Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0020538 (hypertension)
170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adenosine inhibits growth of vascular smooth muscle cells. The goals of this study were to determine which adenosine receptor subtype mediates the antimitogenic effects of adenosine and to investigate the signal transduction mechanisms involved. In rat aortic vascular smooth muscle cells, platelet-derived growth factor-BB (PDGF-BB) (25 ng/mL) stimulated DNA synthesis ([(3)H]thymidine incorporation), cellular proliferation (cell number), collagen synthesis ([(3)H]proline incorporation), total protein synthesis ([(3)H]leucine incorporation), and mitogen-activated protein (MAP) kinase activity. The adenosine receptor agonists 2-chloroadenosine and 5'-N-methylcarboxamidoadenosine, but not N(6)-cyclopentyladenosine or CGS21680, inhibited the growth effects of PDGF-BB, an agonist profile consistent with an A(2B) receptor-mediated effect. The adenosine receptor antagonists KF17837 and 1,3-dipropyl-8-p-sulfophenylxanthine, but not 8-cyclopentyl-1, 3-dipropylxanthine, blocked the growth-inhibitory effects of 2-chloroadenosine and 5'-N-methylcarboxamidoadenosine, an antagonist profile consistent with an A(2) receptor-mediated effect. Antisense, but not sense or scrambled, oligonucleotides to the A(2B) receptor stimulated basal and PDGF-induced DNA synthesis, cell proliferation, and MAP kinase activity. Moreover, the growth-inhibitory effects of 2-chloroadenosine, 5'-N-methylcarboxamidoadenosine, and erythro-9-(2-hydroxy-3-nonyl) adenine plus iodotubericidin (inhibitors of adenosine deaminase and adenosine kinase, respectively) were abolished by antisense, but not scrambled or sense, oligonucleotides to the A(2B) receptor. Our findings strongly support the hypothesis that adenosine causes inhibition of vascular smooth muscle cell growth by activating A(2B) receptors coupled to inhibition of MAP kinase activity. Pharmacological or molecular biological activation of A(2B) receptors may prevent vascular remodeling associated with hypertension, atherosclerosis, and restenosis following balloon angioplasty.
Hypertension 2000 Jan
PMID:A(2B) receptors mediate antimitogenesis in vascular smooth muscle cells. 1064 9

We recently reported that norepinephrine and angiotensin II activate the Ras/mitogen-activated protein (MAP) kinase pathway through generation of a cytochrome P450 (CYP450) and lipoxygenase metabolites. The purpose of this study was to determine the contribution of Ras/MAP kinase to deoxycorticosterone acetate (DOCA)-salt-induced hypertension in rats. Administration of DOCA and 1% saline drinking water to uninephrectomized rats for 6 weeks significantly elevated mean arterial blood pressure (MABP) (166+/-5 mm Hg, n=19) compared with that of normotensive controls (95+/-5 mm Hg, n=7) (P<0.05). The activity of Ras and MAP kinase measured in the heart was increased in DOCA-salt hypertensive rats. Infusion of the Ras farnesyl transferase inhibitors FPT III (138 ng/min) and BMS-191563 (694 ng/min) significantly (P<0.05) attenuated MABP to 139+/-4 mm Hg (n=14) and 126+/-1 mm Hg (n=4), respectively. Moreover, infusion of MAP kinase kinase inhibitor PD-98059 (694 ng/min) also reduced MABP in hypertensive rats. Morphological studies of the kidney showed that treatment of rats with FPT III, which reduced Ras activity, minimized the hyperplastic occlusive arteriosclerosis and fibrinoid vasculitis observed in untreated hypertensive rats. In addition, the rise in CYP450 activity and MABP in hypertensive rats was prevented by the CYP450 inhibitor aminobenzotriazole (50 mg/kg) and was associated with a decrease in Ras and MAP kinase activity in the heart. These data suggest that the Ras/MAP kinase pathway contributes to DOCA-salt-induced hypertension and associated vascular pathology consequent to activation of CYP450.
Hypertension 2000 Jan
PMID:Contribution of Ras GTPase/MAP kinase and cytochrome P450 metabolites to deoxycorticosterone-salt-induced hypertension. 1064 41

We previously showed that arginine vasopressin (AVP) stimulates heat shock protein 27 (HSP27) induction through protein kinase C activation in aortic smooth muscle A10 cells. In the present study, we examined whether the mitogen-activated protein (MAP) kinase superfamily is involved in the AVP-stimulated HSP27 induction in A10 cells. AVP stimulated the phosphorylation of p42/p44 MAP kinase and p38 MAP kinase. On the contrary, AVP had little effect on SAPK (stress-activated protein kinase)/JNK (c-Jun N-terminal kinase) phosphorylation. The HSP27 accumulation by AVP was not affected by PD98059, an inhibitor of the upstream kinase that activates p42/p44 MAP kinase. SB203580 and PD169316, specific inhibitors of p38 MAP kinase, suppressed the AVP-induced accumulation of HSP27. 12-O-tetradecanoylphorbol 13-acetate, an activator of protein kinase C, induced accumulation of HSP27 and was not inhibited by PD98059 but was inhibited by SB203580. Calphostin C and ET-18-OCH(3), inhibitors of protein kinase C, reduced the phosphorylation of p38 MAP kinase by AVP. SB203580 and PD169316 suppressed the AVP-increased levels in mRNA for HSP27. Dissociation of the aggregated HSP27 to the dissociated HSP27 was induced by AVP. These results strongly suggest that p38 MAP kinase takes part in the pathway of the AVP-stimulated induction of HSP27 in vascular smooth muscle cells.
Hypertension 2000 Feb
PMID:p38 MAP kinase is required for vasopressin-stimulated HSP27 induction in aortic smooth muscle cells. 1067 16

A growing body of evidence supports the notion that angiotensin II (Ang II), the central product of the renin-angiotensin system, may play a central role not only in the etiology of hypertension but also in the pathophysiology of cardiovascular and renal diseases in humans. In this review, we focus on the role of Ang II in cardiovascular and renal diseases at the molecular and cellular levels and discuss up-to-date evidence concerning the in vitro and in vivo actions of Ang II and the pharmacological effects of angiotensin receptor antagonists in comparison with angiotensin-converting enzyme inhibitors. Ang II, via AT(1) receptor, directly causes cellular phenotypic changes and cell growth, regulates the gene expression of various bioactive substances (vasoactive hormones, growth factors, extracellular matrix components, cytokines, etc.), and activates multiple intracellular signaling cascades (mitogen-activated protein kinase cascades, tyrosine kinases, various transcription factors, etc.) in cardiac myocytes and fibroblasts, vascular endothelial and smooth muscle cells, and renal mesangial cells. These actions are supposed to participate in the pathophysiology of cardiac hypertrophy and remodeling, heart failure, vascular thickening, atherosclerosis, and glomerulosclerosis. Furthermore, in vivo recent evidence suggest that the activation of mitogen-activated protein kinases and activator protein-1 by Ang II may play the key role in cardiovascular and renal diseases. However, there are still unresolved questions and controversies on the mechanism of Ang II-mediated cardiovascular and renal diseases.
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PMID:Molecular and cellular mechanisms of angiotensin II-mediated cardiovascular and renal diseases. 1069 53

There is a very close interrelationship between the metabolic disorders such as obesity and diabetes mellitus and cardiovascular diseases such as hypertension and atherosclerosis, with insulin resistance and endothelial dysfunction as common features. Insulin has vasculoprotective effects through production of nitric oxide in the endothelial cells, while it produces atherogenic effects by stimulating proliferation and migration of vascular smooth muscle cells(VSMC). The insulin-activated pathway is the phosphatidylinositol 3-kinase pathway in the endothelial cells and MAP kinase pathway in the VSMC. Insulin resistance and hyperinsulinemia may result in the attenuation of the endothelium-mediated action and stimulation of the VSMC-mediated action. Insulin resistance and endothelial dysfunction are related to each other and may cause vicious cycle, leading to the metabolic and cardiovascular diseases.
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PMID:[Insulin resistance and vascular function]. 1070 56

Vascular hypertrophy occurs during chronic hypertension and contributes to the elevation of peripheral vascular resistance in hypertension. In this study, we examined whether acute pressure overloading of the vascular wall produces activation of mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, in isolated perfused rat aortae, and examined whether the mechanical overloading-induced MAP kinase activation is mediated via the vascular angiotensin system. Aortae were perfused with Tyrode solution. Increases in perfusion pressure caused a pressure-dependent increase in MAP kinase activity in endothelium-intact aortae and in endothelium-denuded aortae. The increase in MAP kinase activity induced by pressure loading was inhibited by the angiotensin receptor antagonist, losartan, the renin inhibitor, pepstatin A, and the angiotensin-converting enzyme inhibitor, captopril. Ca(2+) depletion and the Ca(2+) channel antagonist, nifedipine, did not affect the pressure loading-induced MAP kinase activation. The results of the present study suggest that pressure loading of the vascular wall per se can activate MAP kinases in the vasculature and that the MAP kinase activation is mediated at least partly via the vascular angiotensin system. It seems unlikely that the pressure loading-induced increase in MAP kinase activity is mainly mediated via increases in Ca(2+) influx in vascular cells.
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PMID:Angiotensin II mediates pressure loading-induced mitogen-activated protein kinase activation in isolated rat aorta. 1072 70

Chronic stresses, including the mechanical strain caused by hypertension or excess pulmonary ventilation pressure, lead to important clinical consequences, including hypertrophy and acute respiratory distress syndrome. Pathologic hypertrophy contributes to decreased organ function and, ultimately, organ failure; and cardiac and diabetic renal hypertrophy are major causes of morbidity and morality in the developed world. Likewise, acute respiratory distress syndrome is a serious potential side effect of mechanical pulmonary ventilation. Whereas the deleterious effects of chronic stress are well established, the molecular mechanisms by which these stresses affect cell function are still poorly characterized. gene 33 (also called mitogen-inducible gene-6, mig-6) is an immediate early gene that is transcriptionally induced by a divergent array of extracellular stimuli. The physiologic function of Gene 33 is unknown. Here we show that gene 33 mRNA levels increase sharply in response to a set of commonly occurring chronic stress stimuli: mechanical strain, vasoactive peptides, and diabetic nephropathy. Induction of gene 33 requires the stress-activated protein kinases (SAPKs)/c-Jun NH(2)-terminal kinases. This expression pattern suggests that gene 33 is a potential marker for diabetic nephropathy and other pathologic responses to persistent sublethal stress. The structure of Gene 33 indicates an adapter protein capable of binding monomeric GTPases of the Rho subfamily. Consistent with this, Gene 33 interacts in vivo and, in a GTP-dependent manner, in vitro with Cdc42Hs; and transient expression of Gene 33 results in the selective activation of the SAPKs. These results imply a reciprocal, positive feedback relationship between Gene 33 expression and SAPK activation. Expression of Gene 33 at sufficient levels may enable a compensatory reprogramming of cellular function in response to chronic stress, which may have pathophysiological consequences.
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PMID:Gene 33/Mig-6, a transcriptionally inducible adapter protein that binds GTP-Cdc42 and activates SAPK/JNK. A potential marker transcript for chronic pathologic conditions, such as diabetic nephropathy. Possible role in the response to persistent stress. 1074 85

We have reported previously that N-acetyl-L-cysteine facilitated interleukin-1beta-induced nitric oxide synthase (iNOS) expression in rat vascular smooth muscle cells. The present study compares the effect of N-acetyl-L-cysteine with other antioxidants and tested the possibility that N-acetyl-L-cysteine potentiates iNOS induction by a mechanism involving activation of p44/42 mitogen-activated protein kinases (MAPKs). The effect of N-acetyl-L-cysteine on potentiating interleukin-1beta-induced nitrite production and iNOS expression was mimicked either by the enantiomers, L-cysteine and D-cysteine, or by a non-thiol-containing antioxidant, L-ascorbic acid. Interleukin-1beta activated p44/42 MAPK, and this activation was enhanced in the presence of N-acetyl-L-cysteine. Inhibition of p44/42 MAPK phosphorylation by the selective inhibitor PD98059 clearly inhibited iNOS expression induced by interleukin-1beta either in the absence or in the presence of N-acetyl-L-cysteine. These observations, combined with previous results, indicate that p44/42 MAPK activation is required for interleukin-1beta induction of iNOS and that N-acetyl-L-cysteine may act as a reducing agent and facilitate interleukin-1beta-induced iNOS expression through a reduction/oxidation-related mechanism involving potentiation of cytokine activation of the p44/42 MAPK signaling pathway.
Hypertension 2000 Apr
PMID:N-Acetyl-L-cysteine potentiates interleukin-1beta induction of nitric oxide synthase : role of p44/42 mitogen-activated protein kinases. 1077 61

This study examines the involvement of RNA and protein synthesis in the modulation of apoptosis in vascular smooth muscle cells (VSMC) by intracellular monovalent cations. In VSMC transfected with E1A adenovirus (VSMC-E1A), inversion of the [Na(+)](i)/[K(+)](i) ratio by an inhibitor of the Na(+),K(+) pump, ouabain, prevented the development of apoptosis triggered by serum withdrawal. Inhibition of apoptosis by ouabain was abolished by inhibitors of RNA and protein synthesis, actinomycin D, and cycloheximide, respectively. In VSMC-E1A, incubation with ouabain for 4 and 24 hours augmented RNA synthesis by 20% to 50% and 3-fold to 4-fold, respectively. In quiescent VSMC, the effect of ouabain and serum on RNA synthesis was additive. Ouabain did not affect the level of phosphorylation of ERK, JNK, and p38 MAP kinases and blocked apoptosis independent of the presence of the MAPK kinase inhibitors PD98059 and SB 202190. Equimolar substitution of NaCl with KCl in the incubation medium abolished the effect of ouabain on intracellular Na(+) and K(+) concentration, apoptosis, and RNA synthesis. Thus, our results demonstrate that the antiapoptotic effect of the inverted [Na(+)](i)/[K(+)](i) ratio is mediated by MAPK-independent induction of de novo synthesis of RNA species encoding inhibitor(s) of programmed cell death.
Hypertension 2000 May
PMID:Inversion of the intracellular Na(+)/K(+) ratio blocks apoptosis in vascular smooth muscle cells by induction of RNA synthesis. 1081 65

The aim of this study was to test the hypothesis that differences exist in the activity and/or expression of mitogen-activated protein kinases (MAPKs) between spontaneously hypertensive rats (SHR) and control Wistar-Kyoto rats (WKY) and that these differences may account for the enhanced activity of the Na(+)/H(+) exchanger (NHE) previously observed in the renal proximal tubule of SHR. Therefore, the activities of c-jun N-terminal kinase(1) (JNK(1)), extracellular signal-regulated kinase(1/2) (ERK(1/2)), and p38 were investigated. A reduced amount of ERK(1) and JNK(1) protein was found in renal cortex specimens of SHR as compared with WKY; however, their activities were the same. To study the cellular basis of this difference, immortalized proximal tubule cell lines were grown on Millicell-CM filter inserts where the cell lines organize as polarized monolayers with separate access to apical and basolateral compartments. Although basal JNK(1) and ERK(1/2) activities were not significantly different between WKY and SHR cells, anisomycin stimulated JNK(1) activity in WKY cells more than in SHR cells (eg, at 15 minutes 300% versus 30%, respectively). Similarly, angiotensin II increased JNK(1) and ERK(1/2) activity in a time- and concentration-dependent manner in WKY cells but not in SHR cells. Western blot analyses showed a deficit in JNK(1) and ERK(1) protein in SHR (0.25 and 0.5, respectively, of the levels in WKY cells), although ERK(2) and p38 protein levels were the same. These observations suggest that, although angiotensin II activates MAPKs and MAPKs have been shown to regulate NHE, this regulatory pathway is unlikely to account for the increased activity of NHE in the proximal tubular epithelium of SHR.
Hypertension 2000 May
PMID:Activation of MAPKs in proximal tubule cells from spontaneously hypertensive and control Wistar-Kyoto rats. 1081 81


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