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)

Interleukin-1beta (IL-1beta), a proinflammatory cytokine, induces cyclooxygenase-2 (COX-2) in cultured neonatal ventricular myocytes (NVMs), resulting in the preferential production of prostaglandin E(2) (PGE(2)). To explain the preferential PGE(2) release by myocytes, we studied whether its specific synthase, PGE(2) synthase (PGES), is also induced by IL-1beta. Because COX-2 has been extensively associated with cell growth, we questioned whether PGE(2) plays a role in cardiac cell growth. IL-1beta--treated myocytes showed induction of PGES protein and mRNA by Western blot and reverse transcription--polymerase chain reaction, respectively. Immunofluorescence studies revealed perinuclear localization of COX-2 and PGES in IL-1beta--treated myocytes. Exogenous PGE(2) increased protein synthesis in NVMs, as indicated by a 1.6-fold increase in [(3)H]leucine incorporation, comparable to the known hypertrophic factor phenylephrine (1.6-fold). Because PGE(2) exerts different effects through 4 receptor subtypes (EP(1), EP(2), EP(3), and EP(4)), we investigated whether these receptors are functional in myocytes. Treatment of NVMs with the selective EP(1)/EP(3) agonist sulprostone significantly increased protein synthesis (1.7-fold), whereas the EP(1)/EP(2) antagonist AH6809 blocked this effect by 43%. In contrast, AH6809 had no effect on PGE(2)-induced protein synthesis. Regarding second messengers, sulprostone had no effect on cAMP, whereas PGE(2) increased it. We concluded that (1) PGE(2) production requires the induction of its specific synthase; (2) in myocytes, the inducible enzymes COX-2 and PGES are perinuclear; and (3) PGE(2) and sulprostone induce cardiac myocyte growth but seem to activate a different subset of EP receptors.
Hypertension 2002 Feb
PMID:Trophic effects of the cyclooxygenase-2 product prostaglandin E(2) in cardiac myocytes. 1188 77

Many people obtain symptomatic relief from acute, chronic, or recurring pain conditions by using an over-the-counter analgesic. As with the use of any drug, this involves achieving the appropriate balance between potential benefit and risk of harm. The adverse effects of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) in the gastrointestinal (GI) tract are widely appreciated. On the basis of their pharmacology, however, these drugs also have the potential for causing adverse effects in the cardiovascular system. This is particularly the case in certain overlapping populations (eg, the elderly or those with cardiac failure, hypertension, or renal impairment). And the size of the exposed populations and the fact they comprise people likely to require pain management because of concomitant illnesses make the cardiovascular implications of analgesic use potentially a more serious issue for public health than the more widely recognized GI complications of aspirin and NSAID use. This article discusses the impact on the cardiovascular system of different classes of analgesics (NSAIDs, the new cyclooxygenase-2-selective inhibitors [CSIs], and paracetamol) in terms of cardiac function, thrombotic and cardioprotective potential, and hypertension. It identifies patients at risk for analgesic-related cardiovascular adverse events, and considers their options for managing mild-to-moderate pain. Unlike that of the NSAIDs and CSIs, the pharmacology of paracetamol provides no signal for risk of cardiovascular adverse events, and paracetamol should, therefore, be considered as first-line therapy in patients with cardiovascular disease.
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PMID:Areas of emerging interest in analgesia: cardiovascular complications. 1194 85

In the adult rodent kidney cortex, cyclooxygenase-2 (COX-2), NO synthase (NOS1), and renin synthesis change in parallel on alterations in distal tubular NaCl concentration, and their products in part may mutually determine synthesis and activity of these enzymes. Epithelial NO synthesis has been postulated to exert a stimulatory role on COX-2 expression. Changes in COX-2 and NOS1 may be assessed histochemically by determining changes in the number of positive cells. In rat, macula densa and adjacent cells may co-express COX-2 and NOS1, whereas cell groups of the upstream thick ascending limb (cTAL) express COX-2 alone. We have tested whether the stimulation of COX-2 expression by short- and long-term unilateral renal artery stenosis, low salt, and furosemide treatment depends on co-expression of NOS1. These conditions produced significant respective increases (40% to 351%, P<0.05) in the number of COX-2 immunoreactive cells, regardless of whether NOS1 was present or not, suggesting that co-expression of NOS1 is not necessary to produce these changes. Under high-salt conditions, analogous though inverse changes were recorded (-62% to -73%, P<0.05). In mice with genetic deletion of NOS1, low- and high-salt diets caused similar changes of COX-2 immunoreactivity (106% and -52%, P<0.05) than those seen in wild-type mice (43% and -78%, P<0.05). We conclude that alterations of distal tubular NaCl concentration and presumably NaCl transport induce changes in epithelial COX-2 expression that does not depend on presence of co-expressed NOS1. It therefore seems unlikely that NO is part of a signal transduction chain between tubular chloride sensing and the modulating effects of prostaglandins in tubulo-vascular information transfer.
Hypertension 2002 Apr
PMID:Epithelial COX-2 expression is not regulated by nitric oxide in rodent renal cortex. 1196 38

Nonselective nonsteroidal anti-inflammatory agents have been shown to attenuate the antihypertensive efficacy of ACE inhibitors with average increases in systolic blood pressure (BP) of 5 to 10 mm Hg. Less is known about the specific cyclooxygenase-2 (COX-2) inhibitors now widely used for the treatment of arthritis. The objective of this study was to determine the effects of celecoxib compared with placebo on 24-hour BP levels in ACE inhibitor-treated patients with hypertension. This was a randomized, double-blind, placebo-controlled, parallel-group clinical trial involving 178 men and women (mean age, 53 years) with essential hypertension who were treated and controlled with lisinopril monotherapy (10 to 40 mg daily). Baseline BP values were obtained using 24-hour ambulatory recordings. Patients received either celecoxib, 200 mg twice daily (twice the recommended dose for osteoarthritis) (n=91), or placebo (n=87) for 4 weeks, and changes in the 24-hour BP, body weight, and clinical laboratory parameters were assessed. Mean changes from baseline in the 24-hour systolic and diastolic BP were 2.6/1.5+/-0.9/0.6 mm Hg on celecoxib versus 1.0/0.3+/-1/0.6 mm Hg on placebo (P=0.34 for systolic BP; P=0.45 for diastolic BP). The proportion of patients whose 24-hour BP increased by at least 5, 10, 15, or 20 mm Hg were also similar on celecoxib and placebo. No changes in body weight, serum creatinine, or potassium occurred in either group. Thus, these data demonstrate that high doses of celecoxib have no significant effect on the antihypertensive effect of the ACE inhibitor lisinopril. The placebo-subtracted changes observed in 24-hour BP (1.6/1.2 mm Hg) are less than what has been reported for nonselective nonsteroidal anti-inflammatory agents in ACE inhibitor-treated patients.
Hypertension 2002 Apr
PMID:Effects of celecoxib on ambulatory blood pressure in hypertensive patients on ACE inhibitors. 1196 52

Specific inhibitors of cyclooxygenase-2 were introduced into widespread clinical use in 1999. Since that time, celecoxib and rofecoxib have become two of the most commonly prescribed medications in the United States. Clinical trials using these medications for arthritis and pain have uniformly demonstrated efficacy superior to that of placebo and similar to that of nonsteroidal anti-inflammatory drugs. However, controversy surrounding the proper place of cyclooxygenase-2 inhibitors in the hierarchy of treatment for arthritis continues, based primarily on their higher cost compared with that of acetaminophen and nonsteroidal anti-inflammatory drugs. A decreased risk of gastrointestinal toxicity remains the primary justification for using the more expensive cyclooxygenase-2 inhibitors in preference to nonsteroidal anti-inflammatory drugs. The renal and cardiovascular effects of rofecoxib and celecoxib have been investigated in relation to nonsteroidal anti-inflammatory drugs and to one another. The data with respect to alteration in renal function, lower extremity edema, and hypertension indicates that cyclooxygenase-2 inhibitors affect the kidney in a manner similar to that of nonsteroidal anti-inflammatory drugs. The data comparing the cyclooxygenase-2 inhibitors is difficult to interpret because it is not clear that comparable doses have been used in clinical trials. The potential thrombogenic risk of cyclooxygenase-2 inhibitors remains controversial, and conflicting data exist. It remains important to increase our understanding of the place of these agents in clinical practice from the perspective of efficacy, toxicity, and cost.
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PMID:Specific cyclooxygenase-2 inhibitors: what have we learned since they came into widespread clinical use? 1198 17

Increases in blood pressure (BP), particularly systolic BP, have traditionally been considered to be a normal or "physiologic" component of the aging process. However, it is now clear that elevated BP, particularly systolic BP, represents a pathophysiologic manifestation of altered cardiovascular physiology and structure, ultimately manifesting as increased cardiovascular morbidity and mortality (myocardial infarction, stroke, and total cardiovascular death rates). More than one half of the population aged 65 or older have hypertension, defined as BP > or = 140/90 mm Hg. Framingham data indicate that the risk of coronary heart disease increases with lower diastolic BP at any level of systolic BP > or = 120 mm Hg, thus further stressing the importance of pressure-induced arterial vascular compliance changes and introducing pulse pressure as an important predictor of cardiovascular risk. Geriatric hypertension is generally of a salt-sensitive nature and often associated with impaired baroreflex function. Reduction in sodium intake is important and effective in older patients, and should be initiated before or together with drug therapy. Encouraging data from clinical trials now strongly support the aggressive anti-hypertensive treatment of elderly patients. A recent meta-analysis of eight outcome trials evaluating the risks of treated and untreated isolated systolic hypertension has demonstrated a 30% reduction in combined fatal and nonfatal stroke, a 26% reduction in fatal and nonfatal cardiovascular events, and a 13% reduction in total mortality. Those drugs effective in younger patients also appear effective in the elderly; low-dose thiazides (alone or in combination with potassium sparing agents), beta blockers, long-acting dihydropyridine calcium antagonists, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers all have demonstrated efficacy. In selecting an agent, it is important to consider comorbid disease states, and to recognize the potential of all nonsteroidal anti-inflammatory drugs, whether conventional or cyclooxygenase-2 specific, to increase BP or interfere with other antihypertensive agents. In general, the elderly should be treated to target BP levels identical to those suggested for younger patients, although a more gradual reduction to target, perhaps with an intermediate BP goal of < 160 mm Hg, may be advisable.
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PMID:High blood pressure in the geriatric population: treatment considerations. 1209 71

Humans have elevated serum uric acid as a result of a mutation in the urate oxidase (uricase) gene that occurred during the Miocene. We hypothesize that the mutation provided a survival advantage because of the ability of hyperuricemia to maintain blood pressure under low-salt dietary conditions, such as prevailed during that period. Mild hyperuricemia in rats acutely increases blood pressure by a renin-dependent mechanism that is most manifest under low-salt dietary conditions. Chronic hyperuricemia also causes salt sensitivity, in part by inducing preglomerular vascular disease. The vascular disease is mediated in part by uric acid-induced smooth muscle cell proliferation with activation of mitogen-activated protein kinases and stimulation of cyclooxygenase-2 and platelet-derived growth factor. Although it provided a survival advantage to early hominoids, hyperuricemia may have a major role in the current cardiovascular disease epidemic.
Hypertension 2002 Sep
PMID:Uric acid, hominoid evolution, and the pathogenesis of salt-sensitivity. 1221 79

Vascular inflammation was examined as a potential mechanism of aldosterone-mediated myocardial injury in uninephrectomized rats receiving 1% NaCl-0.3% KCl to drink for 1, 2, or 4 wk and 1) vehicle, 2) aldosterone infusion (0.75 microg/h), or 3) aldosterone infusion (0.75 microg/h) plus the selective aldosterone blocker eplerenone (100 mg. kg(-1). day(-1)). Aldosterone induced severe hypertension at 4 wk [systolic blood pressure (SBP), 210 +/- 3 mmHg vs. vehicle, 131 +/- 2 mmHg, P < 0.001], which was partially attenuated by eplerenone (SBP, 180 +/- 7 mmHg; P < 0.001 vs. aldosterone alone and vehicle). No significant increases in myocardial interstitial collagen fraction or hydroxyproline concentration were detected throughout the study. However, histopathological analysis of the heart revealed severe coronary inflammatory lesions, which were characterized by monocyte/macrophage infiltration and resulted in focal ischemic and necrotic changes. The histological evidence of coronary lesions was preceded by and associated with the elevation of cyclooxygenase-2 (up to approximately 4-fold), macrophage chemoattractant protein-1 (up to approximately 4-fold), and osteopontin (up to approximately 13-fold) mRNA expression. Eplerenone attenuated proinflammatory molecule expression in the rat heart and subsequent vascular and myocardial damage. Thus aldosterone and salt treatment in uninephrectomized rats led to severe hypertension and the development of a vascular inflammatory phenotype in the heart, which may represent one mechanism by which aldosterone contributes to myocardial disease.
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PMID:Aldosterone induces a vascular inflammatory phenotype in the rat heart. 1293 35

Concomitant use of nonsteroidal anti-inflammatory drugs (NSAIDs), including the cyclooxygenase-2 (COX-2) specific inhibitors, with antihypertensive medication is common practice for many patients with arthritis. This study evaluated the effects of celecoxib 200 mg/day and rofecoxib 25 mg/day on blood pressure (BP) and edema in a 6-week, randomized, parallel-group, double-blind study in patients > or =65 years of age with osteoarthritis who were treated with fixed antihypertensive regimens. One thousand ninety-two patients received study medication (celecoxib, n = 549; rofecoxib, n = 543). Significantly more patients in the rofecoxib group compared with the celecoxib group developed increased systolic BP (change >20 mm Hg plus absolute value > or =140 mm Hg) at any time point (14.9% vs 6.9%, p <0.01). Rofecoxib caused the greatest increase in systolic BP in patients receiving angiotensin-converting enzyme inhibitors or beta blockers, whereas those on calcium channel antagonists or diuretic monotherapy receiving either celecoxib or rofecoxib showed no significant increases in BP. Clinically significant new-onset or worsening edema associated with weight gain developed in a greater percentage of patients in the rofecoxib group (7.7%) compared with the celecoxib group (4.7%) (p <0.05). Thus, in patients with controlled hypertension on a fixed antihypertensive regimen, careful monitoring of BP is warranted after the initiation of celecoxib or rofecoxib therapy.
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PMID:Effects of celecoxib and rofecoxib on blood pressure and edema in patients > or =65 years of age with systemic hypertension and osteoarthritis. 1274 31

The role of cyclooxygenase-2 (COX-2) in the prolonged regulation of renal function was evaluated during changes in sodium intake and reduction of NO synthesis. It was evaluated in conscious dogs by administering a selective inhibitor (nimesulide) during 8 consecutive days. Nimesulide administration to dogs with normal or high sodium load did not modify glomerular filtration rate but reduced renal blood flow (16%; P<0.05). The vasoconstriction elicited by COX-2 inhibition was greater when NO production was inhibited because glomerular filtration rate decreased by >25% when nimesulide was administered to dogs with a reduced NO synthesis. During low sodium intake, COX-2 inhibition elicited a decrease (P<0.05) of both glomerular filtration rate (34%) and renal blood flow (31%). Sodium excretion only decreased (P<0.05) during the first day of COX-2 inhibition in dogs with normal or high sodium load. The increase in plasma potassium levels elicited by COX-2 inhibition was greater in dogs with low sodium intake and was enhanced when NO production was inhibited. This change in potassium was not secondary to a decrease in plasma aldosterone levels. The results of this study suggest that COX-2-derived metabolites (1) play a more important role in the long-term regulation of renal hemodynamic when sodium intake is low, (2) protect the renal vasculature from the vasoconstriction secondary to a reduction in NO, (3) are only acutely involved in regulating urinary sodium excretion, and (4) play a more important role in regulating plasma potassium concentration when NO synthesis is reduced.
Hypertension 2002 Nov
PMID:Role of cyclooxygenase-2 in the prolonged regulation of renal function. 1241 68


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