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)

Deficiency of either neuronal nitric oxide synthase (NOS1) or endothelial nitric oxide synthase (NOS3) leads to cardiac hypertrophy in mice. Loss of both produces concentric left ventricular (LV) remodeling, in which increased wall thickness is accompanied by reduced cavity size. In humans, this phenotype develops in elderly hypertensive patients and independently predicts mortality. Accordingly, we tested the hypothesis that NOS1/3(-/-) mice have reduced longevity compared to either NOS1(-/-) or NOS3(-/-). Survival data on colonies of NOS1(-/-) (n = 295), NOS3(-/-) (n = 525), and NOS1/3(-/-) (n = 331) mice were collected for 2 years. NOS1(-/-) mice had increased mortality compared to NOS3(-/-) (relative risk, RR 2.5, P < 0.001), whereas NOS1/3(-/-) fared significantly worse (RR 7.3, P < 0.001 vs. NOS3(-/-)). Importantly, gender did not affect survival in NOS1(-/-) or NOS3(-/-), but male NOS1/3(-/-) mice had 2-fold increased mortality compared to females. NOS1/3(-/-) mice developed progressive myocyte hypertrophy and interstitial fibrosis with age. NOS1/3(-/-) mice underwent in vivo hemodynamic analysis with a combined pressure-volume catheter to assess age-related cardiovascular changes. Compared with control, NOS1/3(-/-) demonstrated hypertension and hypercontractility at all ages, and developed passive diastolic dysfunction with increasing age. Thus, combined deficiency of NOS1 and NOS3 causes increased mortality, myocyte hypertrophy, and an age-associated increase in ventricular stiffness. These findings suggest that cardiac NO signals may play an essential role in successful cardiac aging.
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PMID:Combined loss of neuronal and endothelial nitric oxide synthase causes premature mortality and age-related hypertrophic cardiac remodeling in mice. 1278 81

1. The aim of the present study was to investigate whether pre-eclampisa, a state of placental hypoxia, is associated with placental abnormalities in the amount, distribution and expression of endothelial nitric oxide synthase (eNOS). 2. Localization and intensity of eNOS was determined by immunohistochemistry using an antibody specific for eNOS. The amount of eNOS mRNA expression was determined by reverse transcription-polymerase chain reaction (RT-PCR) and the densitometry of gel bands was expressed as a ratio of the band density of the housekeeping gene beta2-microglobulin. 3. Endothelial NOS staining was localized to syncytiotrophoblast cells within the villi and decidual trophoblast cells. It was not present in the endothelium of terminal villous vessels. There was no significant difference in eNOS villous or decidual staining intensity between normal pregnancy (NP; n = 12), pre-eclampsia (n = 14), or gestational hypertension (GH; n = 4). Staining for eNOS was not significantly different in the decidua compared with the villi in NP, GH or pre-eclampsia. Within the decidua, the depth of eNOS staining was similar in NP, pre-eclampisa and GH. 4. There was no significant difference in eNOS mRNA expression between NP (0.70 +/- 0.11), pre-eclampsia (0.5 +/- 0.07) or GH (0.69 +/- 0.26). 5. These findings suggest that the amount of eNOS in the placenta is not deficient in pre-eclampsia, excluding a possible pathogenic role for eNOS in this disease. Furthermore, placental hypoxia, which is associated with pre-eclampsia, did not induce an upregulation of eNOS
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PMID:Placental endothelial nitric oxide synthase localization and expression in normal human pregnancy and pre-eclampsia. 1285 29

Vascular cell adhesion molecule-1 (VCAM-1) and reactive oxygen species play critical roles in early atherogenesis, and nitric oxide (NO) is an important regulator of the cardiovascular system. Although celiprolol, a specific beta1-antagonist with weak beta2-agonistic action, stimulates endothelial nitric oxide synthase (eNOS) production, the mechanisms remain to be determined. Because it was recently reported that phosphatidylinositol 3-kinase (PI3K) and its downstream effector Akt are implicated in the activation of eNOS and that regulation of VCAM-1 expression is mediated via nuclear factor-kappaB (NF-kappaB), we hypothesized that celiprolol activates phosphorylation of eNOS through the PI3K-Akt signaling pathway; that celiprolol modulates VCAM-1 expression, which is associated with inhibiting NF-kappaB phosphorylation; and that celiprolol suppresses NAD(P)H oxidase p22phox, p47phox, gp91phox, and nox1 expression in the left ventricle of deoxycorticosterone acetate (DOCA)-salt hypertensive rats. eNOS and Akt phosphorylation upregulated by celiprolol alone were suppressed by treatment with celiprolol plus wortmannin. Increased expression of VCAM-1, p22phox, p47phox, gp91phox, nox1, activated p65 NF-kappaB, c-Src, p44/p42 extracellular signal-regulated kinases, and their downstream effector p90 ribosomal S6 kinase phosphorylation in DOCA rats was inhibited by celiprolol. Celiprolol administration resulted in a significant improvement in cardiovascular remodeling and suppression of transforming growth factor-beta1 gene expression. In conclusion, celiprolol suppresses VCAM-1 expression because of inhibition of oxidative stress, NF-kappaB, and signal transduction, while increasing eNOS via stimulation of the PI3K-Akt signaling pathway and improving cardiovascular remodeling.
Hypertension 2003 Nov
PMID:Celiprolol activates eNOS through the PI3K-Akt pathway and inhibits VCAM-1 Via NF-kappaB induced by oxidative stress. 1455 79

Pregnancy-induced hypertension in rats with chronic exogenous hyperinsulinemia is associated with reduced urinary excretion of nitric oxide metabolites. We tested the hypothesis that there are perturbations of endothelial nitric oxide synthase in their kidneys. We studied three groups of rats: control pregnant rats (n = 6); pregnant rats with hyperinsulinemia by subcutaneous sustained-release insulin pellet (n = 5); and hyperinsulinemic pregnant rats treated with l-arginine 2 gL in drinking water (n = 5). By the end of pregnancy blood pressure was 78 +/- 12 mm Hg in controls, 119 +/- 15 mm Hg in hyperinsulinemic rats, and 77 +/- 8 mm Hg in l-arginine-treated hyperinsulinemic rats, p < 0.007. Serum creatinine was 0.4 mg/dl in controls, 0.6 mg/dl in hyperinsulinemic rats, and 0.5 mg/dl in l-arginine-treated rats, p < 0.05. Corresponding urinary excretion of nitric oxide metabolites was 2.1 +/- 0.5, 1.2 +/- 0.2, and 1.5 +/- 0.2 micromols/mg creatinine, p < 0.01. Expression of endothelial nitric oxide synthase protein in kidneys by Western blot was not different between controls and hyperinsulinemic rats, 5.6 +/- 2.4 and 5.8 +/- 3.4 OD x mm2, but was nearly doubled in l-arginine-treated rats, 10.8 +/- 2.3, p < 0.03. Thus, the salutary effect of l-arginine on hyperinsulinemic pregnancy-induced hypertension (PIH) may be mediated, in part, by endothelial nitric oxide synthase in their kidneys.
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PMID:Insulin-induced hypertension, L-arginine, and endothelial nitric oxide synthase in pregnant rats. 1457 63

Angiotensin II receptors play an essential role in cardiovascular physiology and disease. The significance of angiotensin type II (AT2) receptors in cardiac disease still remains elusive. Thus, we tested in gene-targeted mice whether AT2 receptors modulate cardiac function and remodeling after experimental myocardial injury. To generate myocardial infarcts of reproducible size, a cryolesion was generated at the free wall of the left ventricle of wild-type mice (Agtr2+/Y) and mice carrying a deletion of the AT2 receptor gene (Agtr2-/Y). Postinjury remodeling was followed up for 4 weeks after cryoinjury. The cryoprocedure led to an increased heart weight/body weight ratio and heart weight/tibia length ratio in AT2-deficient mice compared with control mice. Morphometric analysis revealed a significant increase in myocyte cross-sectional area after cardiac injury (infarct vs sham Agtr2+/Y, +53%; vs Agtr2-/Y, +95%). Expression of endothelial nitric oxide synthase (eNOS) was significantly lower in hearts from Agtr2-/Y than from Agtr2+/Y mice. eNOS downregulation was accompanied by a decrease in cardiac cGMP levels in Agtr2-/Y mice. In isolated murine cardiomyocytes, angiotensin II induced eNOS expression through AT2 receptors, and inhibition of NO production by NG-nitro-l-arginine methyl ester abolished the antihypertrophic effect of AT2 on cardiac myocytes. Our results demonstrate in a genetic mouse model that angiotensin II AT2 receptors exert an antihypertrophic effect in cardiac remodeling after myocardial cryoinjury and link the expression of cardiac eNOS to AT2 receptor activation.
Hypertension 2003 Dec
PMID:Cardiac hypertrophy is associated with decreased eNOS expression in angiotensin AT2 receptor-deficient mice. 1458 Dec 97

Systemic thermal therapy, such as taking a warm-water bath and sauna, induces systemic vasodilation. It was found that repeated sauna therapy (60 degrees C for 15 min) improved hemodynamic parameters, clinical symptoms, cardiac function, and vascular endothelial function in patients with congestive heart failure. Vascular endothelial function is impaired in subjects with lifestyle-related diseases, such as hypertension, hyperlipidemia, diabetes mellitus, obesity, and smoking. Sauna therapy also improved endothelial dysfunction in these subjects, suggesting a preventive role for atherosclerosis. In animal experiments, sauna therapy increases mRNA and protein levels of endothelial nitric oxide synthase (eNOS) in aortas. In normal-weight patients with appetite loss, repeated sauna therapy increased plasma ghrelin concentrations and daily caloric intake and improved feeding behavior. In obese patients, the body weight and body fat significantly decreased after 2 weeks of sauna therapy without increase of plasma ghrelin concentrations. On the basis of these data, sauna therapy may be a promising therapy for patients with lifestyle-related diseases.
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PMID:Clinical implications of thermal therapy in lifestyle-related diseases. 1461 Feb 68

The cluster of risk factors including hyperinsulinemia, insulin resistance, hypertriglyceridemia and hypertension has been called syndrome X. Several evidences link the insulin resistance syndrome with endothelial dysfunction. Since the participation of the renin-angiotensin system (RAS) in this pathology is still unclear, the present study examined the effect of chronic administration of an angiotensin AT1 receptor antagonist, losartan (L), on endothelial nitric oxide synthase (eNOS) activity in aortic endothelium and cardiac tissue, and on the proliferation of primary cultured aortic smooth muscle cells (SMC), obtained from fructose-fed rats (FFR), an experimental model of syndrome X Male Wistar rats were used: Control, FFR and FFR+L (n = 8 in each group). After 8 weeks, tissue samples were obtained and 10% fetal calf serum (FCS) proliferative effect was examined in SMC by 3H-thymidine incorporation and cell counting. The eNOS activity was estimated in aortic endothelial lining and cardiac homogenates by conversion of 3H-arginine into 3H-citrulline. FFR aortic SMC showed a significantly increased 10% FCS-induced 3H-thymidine incorporation and cell number compared to controls. FFR aortic and cardiac eNOS activities were significantly decreased. Chronic treatment with L decreased systolic blood pressure,reverted cardiac hypertrophy, abolished the increased SMC proliferation and restoredeNOS activity. These data confirm that changes in SMC proliferation and endothelial dysfunction at different levels of the cardiovascular system are involved in syndrome "X", and that AT1 receptor blocking can revert those changes, suggesting an important role of the RAS, possibly mediated by AT2 receptors and kinins, in the physiopathological mechanisms of this model.
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PMID:Chronic administration of losartan reverses cardiovascular changes in hypertensive fructose-fed rats. 1465 52

Hypertension in pregnancy (HP), including preeclampsia (PE), is known to be a multifactorial disease. Recently, an Ile105Val variant of the glutathione S-transferase P1 gene ( GSTP1) was shown to be associated with PE in The Netherlands. We therefore performed an association study of the Ile105Val variant comparing 131 patients with HP and 327 normal pregnant controls in Japan. We analyzed the data in the context of other risk factors before pregnancy. The frequency of the Ile/Val+Val/Val genotype of the GSTP1 was not significantly different between the HP (26%) patients and the controls (28%). However, in primiparous patients, the frequency was significantly different in elderly pregnancy (63% in severe HP vs. 18% in controls; P < 0.05), in the subgroup with the MM+MT genotypes of the angiotensinogen gene (50% in severe HP vs. 26% in controls; P < 0.05), and in the subgroup with the GA+AA genotypes of the endothelial nitric oxide synthase gene (42% in severe HP vs. 13% in controls; P < 0.05). These results suggest that this variant of the GSTP1 may play a role in the manifestation of HP together with other independently and/or synergistically acting factors, particularly in primiparous pregnancy.
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PMID:Association between a variant of the glutathione S-transferase P1 gene (GSTP1) and hypertension in pregnancy in Japanese: interaction with parity, age, and genetic factors. 1471 82

We studied the early pathophysiological response of lenticulostriate arterioles in rats in three models of human conditions associated with stroke: (a) chronic angiotensin II-hypertension; (b) chronic nicotine administration; (c) oxidative endothelial injury. In all three models, quantitative patch clamp analysis of freshly isolated vascular smooth muscle cells from lenticulostriate arterioles and posterior cerebral arteries showed significant increases in activity of functional L-type calcium channels that were due to an increase in open channel probability, with no change in other biophysical properties or in channel expression. In addition, all three models showed evidence of endothelial dysfunction, but of a different nature in the three. With chronic angiotensin II-hypertension, but not in the other two models, endothelial nitric oxide synthase (eNOS) was dysfunctional, was mislocalized away from its normal abluminal location, and was accumulated in peri-nuclear Golgi. By contrast, the other two models showed no mislocalization of eNOS, but instead showed evidence of oxidative stress in endothelium, with up-regulation of superoxide dismutase and hexose kinase. All three models showed significant up-regulation of expression of proliferative cell nuclear antigen (PCNA) (PCNA index, 70-80%) in arterioles in situ, which is associated with increased activation of the nuclear transcription factor, phospho-cAMP response element binding protein (phospho-CREB). In addition, calmodulin-dependent protein (CaM) kinase II was activated, in concert with the activation of L-type calcium channels. Furthermore, blockers of either L-type calcium channels (amlodipine) or of CaM kinase II (KN-93) completely prevented the activation of CREB and the up-regulation of PCNA in arterioles. Our findings demonstrate that abnormal regulation of L-type calcium channels is directly responsible for abnormal proliferative responses in vascular smooth muscle in various forms of cerebral arteriolar injury associated with endothelial dysfunction.
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PMID:Early pathophysiological changes in cerebral vessels predisposing to stroke. 1472 53

The peroxisome proliferator activated receptor (PPARgamma) agonist rosiglitazone has been reported to yield cardiovascular benefits in patients by a mechanism that is not completely understood. We tested whether oral rosiglitazone (25 mg/kg per day, 21 days) treatment improves blood pressure and vascular function in a transgenic mouse expressing both human renin and human angiotensinogen transgenes (R(+)A(+)). Rosiglitazone decreased systolic (138+/-5 versus 128+/-5 mm Hg) and mean blood pressure (145+/-5 versus 126+/-7 mm Hg) of R(+)A(+) mice as measured by tail-cuff and indwelling carotid catheters, respectively. Relaxation of carotid arteries to acetylcholine and authentic nitric oxide, but not papaverine, was impaired in R(+)A(+) mice when compared with littermate controls (RA(-)). There were no effects of rosiglitazone on RA(-) mice; however, relaxation to acetylcholine (49+/-10 versus 82+/-9% at 100 micromol/L) and nitric oxide (51+/-11 versus 72+/-6% at 10 micromol/L) was significantly improved in treated R(+)A(+) mice. Rosiglitazone treatment of R(+)A(+) mice did not alter the expression of genes, including endothelial nitric oxide synthase (eNOS), angiotensin 1 receptors, and preproendothelin-1, nor did it alter the levels of eNOS or soluble guanylyl cyclase protein. In separate studies, carotid arteries from R(+)A(+) and RA(-) mice relaxed in a concentration-dependent manner to rosiglitazone, suggesting possible PPARgamma-independent effects in the vasculature. This response was not inhibited with the nitric oxide synthase inhibitor N(omega)-nitro-l-arginine methyl ester (200 micromol/L) or the PPARgamma antagonist bisphenol A diglycidyl ether; 4,4'-isopropylidenediphenol diglycidyl ether (100 micromol/L). These data suggest that in addition to potential genomic regulation caused by PPARgamma activation, the direct effect of rosiglitazone in blood vessels may contribute to the improved blood pressure and vessel function.
Hypertension 2004 Mar
PMID:PPAR(gamma) agonist rosiglitazone improves vascular function and lowers blood pressure in hypertensive transgenic mice. 1474 30


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