Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alterations in calcium metabolism and calcium-regulating hormones have been described in essential hypertension. However, the mechanisms that mediate these responses are unknown. In previous studies, using the genetically spontaneously hypertensive rat and the mineralocorticoid-salt (DOC-salt) hypertensive rat model, we and others have observed that oral calcium supplementation attenuates the associated increase in peripheral vascular resistance and consequently lowers blood pressure (BP). When hypertensive patients (n = 8, diastolic BP 90-95 mmHg (1 mmHg = 133.3 Pa)) were given daily oral calcium supplementation (1.4 g elemental calcium), both systolic and diastolic BP were decreased (5-10 mmHg, p < 0.01). The only biochemical variables significantly changed were serum ionized calcium and intact parathyroid hormone (PTH, 1-84) (p < 0.05); furthermore, the levels of calcitonin gene related peptide (CGRP), measured by both radioimmunoassay and radioreceptor assay, showed a marked 75% increase (p < 0.001). The antihypertensive effects of Ca2+ and the increased levels of CGRP in the circulation returned to baseline levels immediately following cessation of calcium supplementation, suggesting that the effects of calcium on BP and CGRP are specific. On the basis of these observations were proposed that the antihypertensive effect of dietary calcium supplementation, at least in part, is mediated through CGRP.
 ...
PMID:Mechanisms of the antihypertensive effects of dietary calcium and role of calcitonin gene related peptide in hypertension. 884 40

Amylin, a 37-amino acid peptide, is cosecreted with insulin from the beta-cells of the pancreatic islets in normal response to physiological stimuli. It is the major protein of islet amyloid, which is usually present in the pancreases of people with non-insulin-dependent (type II) diabetes mellitus. Amylin elicits potent effects on carbohydrate metabolism in rodent tissues, causing insulin resistance in skeletal muscle and liver. A close structural relationship exists between amylin and the 2 calcitonin gene-related peptides, which are widely distributed neuropeptides and potent vasodilators. These exert biological effects similar to those of amylin on the organs primarily responsible for the regulation of carbohydrate metabolism. All 3 peptides are thought to cause their biological actions by binding to similar cell surface receptors. This article reviews the field of amylin and its role in the physiological regulation of carbohydrate metabolism, and in disease mechanisms associated with insulin resistance in diabetes mellitus, impaired glucose tolerance and essential hypertension. Potential therapeutic applications are also discussed.
 ...
PMID:Amylin, amyloid and age-related disease. 887 14

Parathyroid hormone (PTH), a key hormone regulating plasma Ca level, is elevated in some essential hypertension, and conversly, hyperparathyroidism is associated with elevated blood pressure. However, such an effect would be paradoxical because PTH is a potent vasodilator. Parathyroid hormone-related peptide (PTHrP), which could act in a autocrine and paracrine manner in vascular smooth muscle cells and endothelial cells, would be a more potent vasodilator and could be produced in hypertensive vascular tissue. Calcitonin gene related peptide (CGRP), 37-amino acid neuropeptide results from alternative processing from calcitonin gene, is vasodilating peptide, and is localized in the central and peripheral nervous system involved in cardiovascular regulation. In some essential hypertensive patients, CGRP is reported to be at a low level.
 ...
PMID:[PTH, PTHrP, and CGRP in hypertension research]. 928 6

Insulin as a vascular hormone, apart from its effect on intermediary metabolism, has been considered to play an important role in cardiovascular regulation and pathophysiology of cardiovascular diseases such as essential hypertension, congestive cardiac failure and atherosclerosis. Insulin induces pressor effects by mechanisms of increased sympathetic activity, renal sodium retention and proliferation of vascular smooth muscle cells. On the other hand, accumulating evidence indicates that insulin decreases vascular resistance and increases organ blood flow especially in skeletal muscle tissue, indicating that insulin is a vasodilator. Several mechanisms underlying insulin-induced vasodilation have been proposed. Insulin enhances calcium efflux from vascular smooth muscle cells by activating the plasma membrane Ca(2+)-ATPase and causes hyperpolarization by stimulating Na+, K(+)-ATPase and sodium/potassium pump. Insulin also stimulates nitric oxide (NO) synthase and increases release of NO from vascular endothelium to cause vasodilation. An increase in cyclic AMP levels is induced by insulin, via activation of insulin receptors, beta-adrenoceptors and calcitonin gene-related peptide receptors. However, main cause of mechanisms mediating the vasodilation remain obscure. Hypertension is associated with insulin resistance and hyperinsulinemia. Insulin resistance may contribute to hypertension by sympathetic overactivity, endothelium dysfunction and decreased vasodilator action of insulin. Therefore, insulin must be considered a vasoactive peptide and more investigations are needed to better understand the full significance of the hemodynamic effect of insulin.
 ...
PMID:[Vascular effects of insulin]. 1087 80

Adrenomedullin (ADM), a peptide characterized by persistent hypotensive activity, is thought to be involved when the control mechanism of blood pressure is deranged, because its plasma concentration is upregulated in hypertensive patients. The receptor for ADM, a molecular complex consisting of calcitonin-receptor-like receptor (CRLR) and receptor-activity-modifying protein 2 (RAMP2), is activated through a unique intracellular transport mechanism. By analyzing the nucleotide sequences of bacterial artificial chromosome (BAC) clones, we have established that the gene encoding CRLR is spread over a genomic distance of 103,145 bases; it contains 15 exons interrupted by 14 introns, including 1 that spans more than 60 kilobases. Exons 1-3 constitute the 5' noncoding region; exons 4 through 15 are coding elements, of which exons 8 to 14 encode seven transmembrane domains. Eight novel single-nucleotide polymorphisms (SNPs) and their allelic frequencies in the Japanese population were found by direct sequencing of 32 alleles; two SNPs were in the 5' flanking region, one in exon 2, and the other five around intron-exon junctions. Eight haplotypes were constructed using these alleles in our Japanese population sample. The data establish a basis for investigations to detect molecular variants in the ADM receptor that might alter control of blood pressure and confer on individuals a predisposition to essential hypertension.
 ...
PMID:Human calcitonin receptor-like receptor for adrenomedullin: genomic structure, eight single-nucleotide polymorphisms, and haplotype analysis. 1131 May 80

Isolated segments (1-2 mm) of small subcutaneous arteries (diameter 0.1-0.9 mm) and veins (0.1-1.0 mm) from patients with hypertension (essential n = 13, renovascular n = 6) and controls (n = 17) were examined. The relaxant responses to the sensory transmitters calcitonin gene-related peptide (CGRP) and substance P, and the contractile responses to potassium and noradrenaline were studied. Enhanced dilatory responses (E(max)) but no change in sensitivity (pEC50) were demonstrated in the arteries but not in the veins to CGRP in hypertensives (P < 0.01) as compared with normotensives, and in the hypertensive subgroups (essential hypertension, P < 0.05; renovascular hypertension, P< 0.05). The relaxant responses to substance P were not altered either in arteries or in veins of hypertensives. Furthermore, there were no differences in the contractile responses to 60 mM potassium or to 10 microM noradrenaline between the groups. The results suggest that the enhanced vasodilator response to CGRP in hypertension is an adaptive reaction. The elevated blood pressure may be augmented by vasodilatory activity since different subgroups of hypertensives showed the same results. However, other common characteristics of hypertension (eg, medication, metabolic disturbances) may have also influenced the results.
 ...
PMID:Enhanced vasodilator responses to calcitonin gene-related peptide (CGRP) in subcutaneous arteries in human hypertension. 1184 Feb 30

The kidneys play a pivotal role in the pathogenesis of essential hypertension because of a primary defect in renal hemodynamics and/or tubule hydro-saline handling that results in the retention of fluid and electrolytes. Previous studies have shown that increasing the renal pelvic pressure increased ipsilateral afferent renal nerve activity (ARNA), the ipsilateral renal pelvic release of substance P (SP) and the contralateral urinary sodium excretion in Wistar--Kyoto rats (WKy). However, spontaneously hypertensive rats (SHR) present an impaired renorenal reflex activity associated, partly, with a peripheral defect at the level of the sensory receptors in the renal pelvis. Furthermore, the renal pelvic administration of SP failed to increase ARNA in most of SHR at concentrations that produced marked increases in WKy. Since we have assessed the expression and localization of NK(1) receptor (NK(1)R), SP and calcitonin gene-related peptide (CGRP) in different dorsal root ganglia (DRG) cell subtypes and renal pelvis of 7- and 14-week-old SHR. The results of this study show increased SP and CGRP expression in the dorsal ganglia root cells of SHR compared to WKy rats. Additionally, there was a progressive, significant, age-dependent, decrease in NK(1)R expression on the membrane surface in SHR DRG cells and in the renal pelvis. In conclusion, the results of the present study suggest that the impaired activation of renal sensory neurons in SHR may be related to changes in the expression of neuropeptides and/or to a decreased presence of NK(1)R in DRG cells. Such abnormalities could contribute to the enhanced sodium retention and elevation of blood pressure seen in SHR.
 ...
PMID:Expression and localization of NK(1)R, substance P and CGRP are altered in dorsal root ganglia neurons of spontaneously hypertensive rats (SHR). 1586 22

This review looks at the alterations in the systemic haemodynamics of patients with chronic liver disease (cirrhosis) in relation to essential hypertension and arterial hypertension of renal origin. Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counterregulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin gene-related peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This provides an effective (although relative) counterbalance to raised arterial blood pressure. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development of chronic liver disease, and arterial hypertension is rarely manifested in patients with cirrhosis, even in those with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This probably includes the combination of vasodilatation and vasoconstriction in parallel.
 ...
PMID:Arterial hypertension and chronic liver disease. 1617 91

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin gene-related peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective (although relative) counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.
 ...
PMID:Liver cirrhosis and arterial hypertension. 1652 Nov 78

Migraine is a neurological disorder that is associated with increased levels of calcitonin gene-related peptide (CGRP) in plasma. CGRP, being one of the mediators of neurogenic inflammation and a phenomenon implicated in the pathogenesis of migraine headache, is thus suggested to have an important role in migraine pathophysiology. Polymorphisms of the CALCA gene have been linked to Parkinson's disease, ovarian cancer and essential hypertension, suggesting a functional role for these polymorphisms. Given the strong evidence linking CGRP and migraine, it is hypothesised that polymorphisms in the CALCA gene may play a role in migraine pathogenesis. Seemingly non functional intronic polymorphisms are capable of disrupting normal RNA processing or introducing a splice site in the transcript. A 16bp deletion in the first intron of the CALCA gene has been reported to be a good match for the binding site for a transcription factor expressed strongly in neural crest derived cells, AP-2. This deletion also eliminates an intron splicing enhancer (ISE) that may potentially cause exon skipping. This study investigated the role of the 16bp intronic deletion in the CALCA gene in migraineurs and matched control individuals. Six hundred individuals were genotyped for the deletion by polymerase chain reaction followed by fragment analysis on the 3130 Genetic Analyser. The results of this study showed no significant association between the intronic 16bp deletion in the CALCA gene and migraine in the tested Australian Caucasian population. However, given the evidence linking CGRP and migraine, further investigation of variants with this gene may be warranted.
 ...
PMID:Association study of calcitonin gene-related polypeptide-alpha (CALCA) gene polymorphism with migraine. 2119 98


<< Previous 1 2 3 4 Next >>