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)

Calcitonin gene-related peptide (CGRP), a highly potent vasodilator, is expressed from the calcitonin-gene and has been localized to nerve fibers of the cardiovascular system, suggesting involvement in the physiologic regulation of vascular tone. In this investigation serum concentrations of CGRP were measured in patients with untreated mild to moderate essential hypertension (WHO I-II) and compared with concentrations in sex- and age-matched normal controls to assess a possible relationship between changes in concentrations of CGRP and this condition. The study showed no significant difference in concentrations of CGRP between patients and the normotensive controls. However, a weak but significant positive correlation was found between systolic (SBP), diastolic (DBP), mean blood pressures (MBP), and circulating concentrations of CGRP when calculated for all individuals included in the study. No correlation was found between heart rates (HR) and concentrations of CGRP. In the normotensive control group, but not in patients with hypertension, a significant positive correlation was present between body weights and concentrations of CGRP. These findings do not support the hypothesis that low expression of CGRP plays a causal role in essential hypertension, but the results do not exclude a potential receptor defect for CGRP to be involved in the disease.
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PMID:Normal serum levels of calcitonin gene-related peptide (CGRP) in mild to moderate essential hypertension. 187 10

1 We investigated the peripheral haemodynamic effects of human alpha-calcitonin gene-related peptide (CGRP) following administration of endothelin-1 or NG-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide production, in conscious, chronically-instrumented, Long Evans rats. 2 Infusion of endothelin-1 (3 nmol kg-1 h-1) caused hypertension, bradycardia and renal, mesenteric and hindquarters vasoconstrictions. Co-infusion of human alpha-CGRP (1.5 nmol kg-1 h-1) reduced the hypertension and abolished the hindquarters vasoconstriction caused by endothelin-1 but the renal and mesenteric vasoconstrictor actions of endothelin-1 were not affected. 3 Infusion of human alpha-CGRP (15 nmol kg-1 h-1) in the presence of endothelin-1 caused hypotension and hyperaemic vasodilatation in the hindquarters; the mesenteric vasoconstrictor effects of endothelin-1 were diminished, but there was only a transient reversal of the renal vasoconstrictor effects of endothelin-1. 4 Pretreatment with the non-peptide angiotensin II receptor antagonist, DuP 753 (10 mg kg-1), caused slight hypotension associated with renal, mesenteric and hindquarters vasodilatations, but DuP 753 did not affect responses to endothelin-1 infusion. However, under these conditions co-infusion of human alpha-CGRP (15 nmol kg-1 h-1) caused a sustained reversal of the renal vasoconstrictor effects of endothelin-1. 5 These results indicate that the failure of human alpha-CGRP to cause sustained reversal of the renal vasoconstrictor effects of endothelin-1 in the absence of DuP 753 was due to activation of the reninangiotensin system (possibly as a consequence of the hypotension). 6. In the second experiment, L-NAME (l0mgkg-1) caused renal, mesenteric and hindquarters vasoconstrictions similar to those seen in the presence of endothelin-1. However, the renal vasoconstrictor effects of L-NAME were reversed completely by human alpha-CGRP (l5nmolkg- h-1), even though the latter caused hypotension comparable to that seen in the presence of endothelin-1. These results are consistent with a lack of functional activation of the renin-angiotensin system by human alpha-CGRP in the presence of L-NAME. 7. The vasoconstrictor effects of L-NAME on the hindquarters were completely reversed by infusion of human alpha-CGRP, but hindquarters flow and vascular conductance did not rise above baseline levels. Hence these results indicate the hindquarters hyperaemic vasodilator effects of human alpha-CGRP seen in the presence of endothelin-1 were contributed to by nitric oxide-mediated mechanisms.
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PMID:Haemodynamic effects of human alpha-calcitonin gene-related peptide following administration of endothelin-1 or NG-nitro-L-arginine methyl ester in conscious rats. 187 60

In addition to the classical transmitters noradrenaline and acetylcholine, other transmitters have been identified in perivascular nerves, including 5-hydroxytryptamine, ATP and a number of peptides. This paper discusses pre- and postjunctional neuromodulation of vascular transmission, and cotransmission involving noradrenaline, ATP and neuropeptide Y in sympathetic nerves, acetylcholine and vasoactive intestinal polypeptide in parasympathetic nerves, and substance P, calcitonin gene-related peptide and ATP in 'sensory-motor' nerves. Vasomotor nerves derived from intrinsic neurones, for example in the heart and gut, are also discussed. Subpopulations of endothelial cells store and release a variety of substances, including acetylcholine, substance P, ATP, 5-hydroxytryptamine, vasopressin and angiotensin II, that act on receptors on endothelial cells and lead to the production of endothelium-derived relaxing factor (identified as nitric oxide) which, in turn, produces vasodilation in response to changes in flow and hypoxia. Endothelium-derived contracting factors such as endothelin may also be released. There appears to be a resting dynamic balance between endothelium-derived vasodilator tone and sympathetic vasoconstrictor tone, which is altered under different physiological and pathophysiological circumstances. Long-term (trophic) interactions between perivascular nerves and endothelial cells are discussed, as are the changes in vascular control mechanisms that occur with ageing and hypertension and in the nerves that remain following trauma or surgery.
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PMID:Local mechanisms of blood flow control by perivascular nerves and endothelium. 198 71

We now describe the effects of calcitonin gene-related peptide (CGRP) on [3H]norepinephrine (NE) release in medulla oblongata of spontaneously hypertensive rats (SHR). CGRP inhibited stimulation-evoked [3H]NE release in a dose-dependent manner in Sprague-Dawley rats, although the basal release of [3H]NE was not affected by the peptide. In SHR, the inhibitory effect of CGRP on stimulation-evoked [3H]NE release was significantly attenuated compared with Wistar Kyoto rats. These results suggest that CGRP might be involved in the regulation of central sympathetic nervous activity in hypertension.
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PMID:Effects of calcitonin gene-related peptide on [3H]norepinephrine release in medulla oblongata of spontaneously hypertensive rats. 209 96

If we consider the chemical messengers in the central nervous system, there are about ten classic transmitters--the catecholamines, biogenic amines and amino acids--as opposed to over 50 different neuropeptides. These include previously well-established circulating hormones such as angiotensin, atrial natriuretic peptide, vasopressin and oxytocin, calcitonin and calcitonin gene related peptide (CGRP), the opioid family of peptides, gastrointestinal peptides, pituitary peptides and their releasing factors, and miscellaneous peptides such as the kinins, bombesin, gallanin, and others; all occur as neuropeptides in the brain. There is evidence supporting a role in central cardiovascular control for angiotensin, opioid peptides, substance P, neuropeptide Y, vasopressin, atrial natriuretic peptide, kinins, corticotropin releasing factor, bombesin, somatostatin, and some other peptides. They have been localized in brain areas known to be important for blood pressure regulation, and specific high-affinity peptide receptors have also been discovered. Upon central administration, these peptides produce cardiovascular effects, partly by interacting with other blood pressure-controlling neuroregulators, e.g. catecholamines and GABA. Central inhibition of brain peptide synthesis or interaction with competitive antagonists at the receptor site results in marked cardiovascular effects. Altered peptide levels and activity of synthesizing enzymes, as well as supersensitivity to the pressor action of some brain peptides, have been described in experimental models of hypertension. We are using angiotensin as a model peptide to study the peptidergic control of cardiovascular function.
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PMID:Peptidergic control of cardiovascular function: the angiotensin paradigm. 219 11

Although altered cellular calcium handling plays a critical role in the pathophysiology of hypertension, little attention has been focused on the impact of calcium regulating hormones on this process. Recent research provides evidence that parathyroid hormone, calcitonin, 1,25-dihydroxyvitamin D, as well as newly described factors such as calcitonin gene-related peptide (CGRP), exert target-organ-specific actions in cardiac and peripheral vascular tissues, are linked to the renin-aldosterone system, and thus to the control of sodium metabolism, and may directly participate in the hypertensive process, especially in low renin and salt sensitive forms of hypertensive disease. The metabolic set-point of these linked renin and calcium hormone systems, which serve to transduce environmental dietary mineral signals at the cellular level, determines the blood pressure consequences of sodium and calcium loading and/or restriction, and helps to explain the heterogeneous and seemingly inconsistent effects of these dietary maneuvers on blood pressure. Measurement of renin and calcium factors in hypertension thus provides a physiological basis for individualized therapeutic recommendations in human hypertension.
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PMID:Calciotropic hormones in human and experimental hypertension. 222 65

Aging is characterized, besides other changes, by a progressive increase in calcium content in the arterial wall, which is enhanced by diabetes mellitus, osteoporosis, arterial hypertension, and tabagism. As to tabagism, experiments in animals have shown that nicotine can increase calcium content of the arterial wall, and clinical studies have demonstrated that cigarette smoking induces peripheral vasoconstriction, with consequent increase in blood pressure levels. In order to study the role of calcium ions in the pathogenesis of the vasoconstrictive lesions caused by "acute" smoking, the author has studied the peripheral vascular effects of the calcium-channel antagonist nifedipine, a dihydropyridine derivative, and calcitonin, a hypocalcemizing hormone which possess vasoactive actions on 12 elderly regular smokers (mean age 65.8 years). The results demonstrated that both nifedipine (10 mg sublingually 20 min before smoking) and salmon calcitonin (100 MRC U/daily intramuscularly for three days) are able to prevent peripheral vasoconstriction evaluated by Doppler velocimetry, as well as the increase of blood pressure induced by smoking. On the basis of our results, the author proposes that cigarette smoking-induced vasoconstriction is a calcium-mediated process, which can be hindered by drugs with calcium antagonist action.
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PMID:Smoking, calcium, calcium antagonists, and aging. 222 75

The role of calcitonin gene-related peptide (CGRP)-containing vasodilator nerves in maintenance of hypertension was investigated in the perfused mesenteric vascular beds isolated from spontaneously hypertensive rats (SHR), deoxycorticosterone-salt-induced hypertensive rats (DOCA-Salt-HR) and corresponding normotensive control rats (Wistar Kyoto rats, WKY and Wistar rats, NR). In the mesenteric artery with an active tone, the neurogenic vasodilation induced by perivascular nerve stimulation (PNS, 0.5-8 Hz), which was mediated by CGRP nerves, was markedly decreased in adult SHR (15-week-old) when compared with age-matched WKY, whereas the vasodilation in DOCA-Salt-HR was similar in magnitude to that in NR. The vasodilator response to exogenously applied CGRP was greater in SHR than in WKY, whereas no difference was found between DOCA-Salt-HR and NR. The neurogenic release of CGRP-like immunoreactivity (CGRP-LI) induced by PNS of the mesenteric artery was significantly decreased in SHR compared to that of WKY. In addition, immunohistochemical studies showed decreased populations of CGRP-LI fibers in the mesenteric artery of SHR compared to those in WKY. These results suggest that CGRP-containing vasodilator innervation is greatly decreased in SHR with established hypertension. It is also suggested that the decreased vasodilator mechanism by CGRP-containing nerves contributes to the maintenance of hypertension.
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PMID:Changes in calcitonin gene-related peptide (CGRP)-containing vasodilator nerve activity in hypertension. 239 Jul 22

We previously demonstrated that the mesenteric resistance blood vessels have nonadrenergic, noncholinergic vasodilator innervation in which calcitonin gene-related peptide (CGRP) is a possible neurotransmitter. The role of CGRP-containing vasodilator nerves in hypertension was investigated in perfused mesenteric vascular beds isolated from spontaneously hypertensive rats (SHR). The adrenergic vasoconstrictor responses to perivascular nerve stimulation in both SHR (8-, 15-, and 30-week-old) and age-matched Wistar-Kyoto (WKY) rat preparations increased with aging, but the response was greater in SHR than in WKY rats at all ages. The preparation isolated from SHR and WKY rats was precontracted by continuous perfusion of Krebs' solution containing 7 x 10(-6) M methoxamine plus 5 x 10(-6) M guanethidine. In both SHR and WKY rats, perivascular nerve stimulation (1-8 Hz) produced frequency-dependent vasodilation, which was blocked by 1 x 10(-7) M tetrodotoxin, pretreatment with 5 x 10(-7) M capsaicin, and denervation by cold storage (4 degrees C for 72 hours). The vasodilation induced by perivascular nerve stimulation in SHR greatly decreased with age, whereas a slight decrease in the response with age was found in WKY rats. The neurogenic vasodilation in the young SHR preparation was similar in magnitude to the vasodilation in age-matched WKY rats, whereas the vasodilation in 15- and 30-week-old SHR was significantly smaller than that in age-matched WKY rats. In both SHR and WKY rats, perfusion of rat CGRP (1 x 10(-10) to 3 x 10(-8) M) produced marked vasodilation in a concentration-dependent manner. The CGRP-induced vasodilation in SHR increased with age, whereas an age-related decrease in vasodilation was found in WKY rats. Perivascular nerve stimulation (4 and 8 Hz) of the perfused mesenteric vascular bed evoked an increased release of CGRP-like immunoreactive substance in the perfusate, which was significantly less in 15-week-old SHR than in age-matched WKY rats. Immunohistochemical studies showed an age-related decrease in CGRP-like immunoreactive fibers in SHR but not in WKY rats. These results suggest that CGRP-containing vasodilator innervation is greatly decreased when SHR develop and maintain hypertension. It is also suggested that the decreased vasodilator mechanism by CGRP-containing nerves contributes to the development and maintenance of hypertension.
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PMID:Age-related decrease of calcitonin gene-related peptide-containing vasodilator innervation in the mesenteric resistance vessel of the spontaneously hypertensive rat. 239 78

In the present study, the mean arterial pressures (MAP) and heart rates (HR) were measured in Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) that had received a 10-day continuous subcutaneous infusion of either saline or the centrally acting alpha-adrenoceptor agonist clonidine (10 micrograms/kg/h). In separate groups of similarly treated rats, the concentrations of neurotensin (NT), vasoactive intestinal polypeptide (VIP), cholecystokinin octapeptide (CCK-8), calcitonin gene-related peptide (CGRP), and neuropeptide Y (NPY) were measured in the cortex (COR), hypothalamus (HYP), medulla oblongata/pons (MO/P), and cervical (CSC) and thoracic (TSC) spinal cord. In comparison to the WKY rats, the SHR had significantly lower neuropeptide concentrations within the COR (NPY, CCK-8), HYP (NT), MO/P (NPY, NT, and CCK-8), CSC (all neuropeptides), and TSC (NPY, NT, CCK-8, and VIP). The infusion of clonidine lowered the MAP of the WKY and SHR rats (-10 and -35 mm Hg, as compared with respective saline controls) and HR in the WKY rats (-45 beats/min). In general, the infusion of clonidine produced decreases in neuropeptide levels within the CNS of the WKY rather than the SHR strain. When there was a strain difference (i.e., SHR less than WKY), it was evident, particularly within the spinal cord, that clonidine reduced the levels of the neuropeptides in the WKY rats to those levels in the SHR. These findings suggest that the reduced neuropeptide concentrations of the SHR (particularly those within the CSC) and TSC may be a result of, rather than a causal factor in, hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regional brain concentrations of several putative peptide neurotransmitters in normotensive and spontaneously hypertensive rats: effects of continuous (10-day) clonidine infusion. 245 67


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