Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The endothelium modulates coronary vascular tone by the release of endothelium-derived relaxing or contracting substances. The endothelium-derived relaxing factor has been identified as nitric oxide synthesized in endothelial cells from L-arginine. The endothelium can release other relaxing substances such as prostacyclin and a hyperpolarizing factor. Endothelin-1 is a potent vasoconstrictor peptide formed by endothelial cells, and is likely to be the physiologic antagonist of endothelium-derived relaxing factor. Other putative contracting factors include superoxide anions and products of arachidonic acid metabolism. Endothelium-derived relaxing factor is released spontaneously and in response to flow, platelet-derived products (that is, serotonin, thrombin and adenosine diphosphate) and certain autacoids (that is, acetylcholine, bradykinin, histamine, substance P, vasopressin, alpha-adrenergic agonists). A considerable heterogeneity of responses exists among vessels of different size from different anatomic origin and different species. Hypercholesterolemia, atherosclerosis, hypertension and myocardial ischemia or reperfusion, or both, impair endothelium-dependent relaxation. Under normal conditions, endothelium-derived relaxing factor appears to dominate the control of vascular tone of large and small coronary vessels, whereas in disease states, endothelium-derived contracting factors are released. Impairments of endothelial function may be important in the development of various forms of cardiovascular disease.
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PMID:Endothelial control of vascular tone in large and small coronary arteries. 240 18

PGI2, or prostacyclin, and PGE2 are major derivatives of arachidonic acid. Arachidonic acid is converted by the cyclooxygenase enzyme to intermediate prostaglandin endoperoxides which are then enzymatically converted to PGI2 and PGE2 as well as to thromboxane A2 and PGF2 alpha. Aspirin and other nonsteroidal anti-inflammatory drugs inhibit the cyclooxygenase enzyme thereby reducing the amount of PGE2 and PGI2 produced. In the kidney, major stimuli of prostaglandin synthesis include vasoconstrictor hormones such as angiotensin II, vasopressin, endothelin and norepinephrine. Renal PGI2 and PGE2 synthesis is also increased after renal ischemia, immune injury to the kidney, and with renal parenchymal disease. Renal prostaglandin production also increases with severe arteriosclerotic cardiovascular disease, congestive heart failure, and severe hepatic disease. The increment of renal prostaglandin synthesis is important since PGI2 and PGE2 act as modulators of renal ischemia and vasoconstriction. The modulatory action leads to a negative feedback loop through which PGE2 and PGI2 and renal blood vessels in glomeruli reduce the vasoconstrictor action of the agonist, such as angiotensin II or norepinephrine. Nonsteroidal anti-inflammatory drugs can have nephrotoxic effects if they are used in clinical situations in which renal prostaglandin synthesis has increased compensatorily. In other words, the administration of indomethacin or other prostaglandin inhibitory drugs will reduce renal blood flow and glomerular filtration rate in patients with congestive heart failure, significant hepatic disease, or renal ischemia and vasoconstriction. PGI2 and PGE2 may have additional beneficial effects within the kidney in addition to being vasodilatory.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prostaglandin I2 and the kidney. 251 64

Today, the endothelium can be considered a multifunctional "organ". In addition to its well-known role as a thrombophobic, semi-permeable barrier between the circulating blood and the extravascular space, it is now known to have major metabolic and synthesizing properties. In addition to prostacyclin, the endothelial cells also produce an endothelial relaxing factor (EDRF). These two substances bring about a dilatation of the smooth vascular muscles, and can inhibit platelet aggregation. The recently identified substance endothelin, which is also produced by the endothelium, appears to have mainly vasoconstrictive properties. In addition to an effect on endocrine parameters, e.g. enhanced liberation of vasopressin, aldosterone, atrial natriuretic peptide and renal parameters (reduced secretion of Na+) it is also reported to interact with prostacyclin and EDRF. Malfunctioning or injuries of the endothelium that, among other things, lead to a reduced synthesis of the relaxing substances or an increase in the production of endothelial vasoconstrictive substances, may have an influence on the pathogenesis of cardiovascular disease.
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PMID:[The endothelium--a microcosm of cardiovascular regulation]. 268 18

Study I: A retrospective survey of the data base on serum electrolyte measurements in our hospital (approximately 50,000 cases) revealed that the incidence of hyponatremia increased with age. Its major cause in the elderly hospital inpatients with cardiovascular disease was congestive heart failure, frequently accompanied by renal dysfunction and the use of diuretics. Another interesting finding from this analysis was that the use of potassium sparing diuretics were often associated with hyperkalemia in elderly patients whose renal functions were apparently normal based on the serum creatinine level. Study II: The resting hemodynamics and the plasma levels of various hormones related to water and electrolyte metabolism were compared between normal elderly and young subjects. The resting hemodynamic parameters, including cardiac index and blood pressure, did not differ between the two normal groups. Plasma atrial natriuretic peptide and norepinephrine levels were significantly higher in the elderly, while plasma renin activity and aldosterone levels were significantly decreased. No differences were observed in antidiuretic hormone levels. The same parameters were then compared between normal and hypertensive elderly subjects. Elderly hypertensives had lower cardiac index and higher peripheral resistance than normal elderly subjects. Plasma norepinephrine level and plasma renin activity were lower, but aldosterone level was not significantly lower in hypertensives than in normotensives. There was no difference in antidiuretic hormone. In the elderly group as a whole, atrial natriuretic peptide correlated positively with blood pressure, and negatively with plasma norepinephrine and renin activity. Multivariate analysis showed that the strongest correlation was that with plasma renin activity. These results suggest that the plasma levels of various hormones related to water and electrolyte metabolism were altered with age and hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Water and electrolyte metabolism in the elderly with cardiovascular disease--hormonal aspects in elderly hypertension]. 279 73

The acute effects of 50 mg of ibopamine (SB-7505), the 3,4-diisobutyryl ester of N-methyldopamine, were investigated after oral administration to 10 adult subjects without evidence of renal, hepatic or cardiovascular disease. Blood pressure and heart rate did not change while diuresis and urinary electrolyte excretion increased significantly during the 240 min of the study. Glomerular filtration rate (GFR) was also increased at 80 min after ibopamine, whereas plasma aldosterone and prolactin were slightly decreased. In contrast to dopamine, ibopamine did not stimulate plasma renin activity. These results are attributable to the ability of ibopamine to be rapidly deesterified to N-methyldopamine (epinine) which has been previously shown to exert peripheral effects similar to those of dopamine. Therefore, the increased GFR can be ascribed to an enhanced renal blood flow. On the contrary, taking into account the significant increase of the fractional excretion of sodium (FeNa) the rise in sodium excretion seems to be the consequence of a direct tubular effect of epinine, even though the slight decrease in peripheral aldosterone concentration would have been a contributing factor. Urinary flow rate might be enhanced by the high sodium delivery to the distal nephron, rather than by a postulated dopaminergic inhibition of arginine-vasopressin release.
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PMID:Humoral and renal effects of ibopamine in normal subjects. 351 27

Historically, the sodium ion has been given prominence in relation to cardiovascular disease, perhaps to the exclusion of other ions. Recently, other ions, including chloride, potassium, magnesium and calcium have received increasing attention in relation to hypertension, cardiac arrhythmias, and metabolic derangements. Endocrine factors controlling these ions have also received increasing attention; they include classic hormonal actions as well as neurotransmission and paracrine hormonal actions. Studies indicate that control of the renin-angiotensin-aldosterone system resides in cytosolic calcium ion levels in the juxtaglomerular cell, as well as chloride ion and prostaglandins at the macula densa. Renin release is stimulated by hyperpolarisation of the juxtaglomerular cell induced by beta 1-agonists, parathyroid hormone, glucagon, magnesium and low cytosol calcium. Renin release is inhibited by high calcium, potassium and angiotensin II. Subsequent to renin release, hormonal regulation includes stimulation of converting enzyme activity by cortisol and prostaglandin (PGE2). Other hormonal control includes antidiuretic hormone producing dilution of extracellular electrolytes and augmented peripheral resistance. A recently identified natriuretic factor isolated from cardiac atria appears to be a potent diuretic with actions similar to that of frusemide (furosemide). Other electrolytes have received closer scrutiny. Chloride may play a dominant role in renal sodium reabsorption, responding to prostaglandin levels. Calcium has been recognised as a basic regulator of the secretion of such hormones as noradrenaline, renin, and aldosterone. As well, calcium ion changes are the means by which smooth muscle contraction is effected. Parathyroid hormone and vitamin D regulate the level of this ion in the body. In addition, a high dietary calcium intake appears to play a protective role against hypertension, while calcium channel blockers appear to reduce blood pressure. Endocrine systems play a major role in the protection against acute elevations in serum potassium by means of insulin action and adrenergic modulation of extrarenal potassium disposal. Aldosterone is recognised as the delayed regulator of potassium excretion. Magnesium levels fall in hyperaldosteronism, hyperparathyroidism, and diabetic keto-acidosis, as well as in malnutrition states. A coexisting potassium deficiency may be refractory to therapy until hypomagnesaemia is corrected. The integrated action of these hormones and electrolytes are thus of major importance in regulation of the cardiovascular system.
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PMID:Endocrine physiology of electrolyte metabolism. 638 78

Ornipressin (OR), a synthetic derivative of natural vasopressin, is widely used in combination with local anaesthetics in order to reduce surgical bleeding and systemic absorption of the local anaesthetic. As shown previously in experimental studies, OR causes severe coronary vasoconstriction. The myocardial oxygen balance is compromised by an increase in myocardial oxygen demand due to hypertension and impaired oxygen delivery following coronary vasoconstriction. We describe the case of a 19-year-old male who was admitted to the hospital for elective tonsillectomy. There was no evidence of systemic or cardiovascular disease (ASA I). Following the induction of anaesthesia with thiopentone 4 mg/kg and ventilation with N2O/O2 (FiO2:0.25), vecuronium was administered to facilitate orotracheal intubation. Anaesthesia was maintained with N2O/O2 (FiO2:0.33) and 2 MAC isoflurane. After reaching an anaesthetic steady state with stable haemodynamic conditions, peritonsillar infiltration with a prilocaine solution containing a total of 0.8 IU OR (0.1 IU/ml) produced marked tachycardia and hypertension. Concomitantly, distinct ST-segment-depression was observed in a lead II ECG. Hypertension and tachycardia occurred within 3 min after the local infiltration with prilocaine/OR. Maximum ST-segment depression and haemodynamic changes were recorded 11 min after infiltration, with an increase in heart rate from 58 to 136 min and a rise in blood pressure from 115/50 to 217/130 mmHg. Considering experimental results, the ECG changes in this case show clear evidence that even in healthy humans OR-induced systemic haemodynamic changes may be complicated by severe myocardial ischaemia due to coronary vasoconstriction.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Signs of a severe myocardial ischemia following peritonsillar infiltration with ornipressin (POR 8)]. 831 91

Acute bleeding due to esophageal varices continues to be a life-threatening complication of liver disease. Despite the availability of improved therapy, mortality continues to be high. Octreotide has been shown to be at least as effective as vasopressin in the treatment of bleeding varices, with fewer and less severe systemic adverse effects. In addition, octreotide has also been consistently associated with a decreased need for transfusions. Octreotide has been used safely in patients without serious cardiovascular disease when administered as a continuous intravenous infusion of 25 micrograms/h for 24 hours with or without an initial 100-micrograms bolus dose. Since these trials have used small numbers of patients, the ability to detect small but clinically important differences has been limited. Additional controlled trials comparing octreotide with the combination of vasopressin and nitroglycerin are needed to more clearly determine the efficacy and cost-effectiveness of therapy. Furthermore, the optimal dosage, duration, and route of administration of octreotide in the treatment of bleeding esophageal varices has yet to be determined.
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PMID:Octreotide or vasopressin for bleeding esophageal varices. 903 26

Stress or noxious stimuli of various kind may induce the fight-flight response. In this situation a number of physiological and behavioural adaptations leading to defense of the organism occur. At a central level increased activity in the noradrenergic locus coeruleus (LC) and an enhanced secretion of corticotrophin-releasing factor (CRF) and vasopressin produced in the paraventricular nucleus (PVN) integrate stress response. Here the existence of an opposite psycho-physiological pattern associated with relaxation and growth and which is activated by certain types of non-noxious stimuli and integrated by oxytocin is proposed. In support of this, administration of oxytocin to male and female rats gives rise to effects of antistress nature in particular after repeated administration. Thus a five day treatment period with oxytocin 1 mg/kg s.c. or 1 micro g/kg i.c.v gives rise to sedation, lowering of blood pressure, increased withdrawal latency in the tail flick test and also a decrease of corticosterone levels and a rise of certain vagally controlled hormones. Weight gain is also increased under certain conditions. These effects persist several weeks after administration of oxytocin and cannot be reversed by oxytocin antagonists when established, suggesting that secondary mechanisms have been activated. Naloxone temporarily reverses the increased withdrawal of the tail flick test suggesting that opioid mechanisms have been activated to cause this particular effect. In contrast the sedative and blood pressure lowering effect seems to be induced by an enhanced activity in central alpha 2 receptors. Oxytocin levels increase in blood and CSF after various kinds of non-noxious sensory stimulation such as touch, light pressure and warm temperature in both female and male rats. It is suggested that other types of non-noxious stimuli as well may increase oxytocin release. If so, a release of oxytocin could be responsible for not only the antistress effects occurring during lactation but also why relationships, social contact and networks may have health promoting effects in particular by preventing cardiovascular disease.
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PMID:Oxytocin linked antistress effects--the relaxation and growth response. 940 3

Several angiotensin II receptor blockers (ARBs), including candesartan cilexetil, irbesartan, losartan, telmisartan, and valsartan, are currently approved by the US Food and Drug Administration (FDA) for the treatment of patients with hypertension. These agents share a common mechanism of action-antagonism of the angiotensin type 1 (AT1) receptor-and as a result, they block a number of angiotensin II effects that are relevant to the pathophysiology of cardiovascular disease, including vasoconstriction, renal sodium reabsorption, aldosterone and vasopressin secretion, sympathetic activation, and vascular and cardiac hyperplasia and hypertrophy. Unlike the angiotensin converting enzyme (ACE) inhibitors, these new drugs block the effects of angiotensin II regardless of whether it is produced systemically in the circulation or locally via ACE- or non-ACE-dependent pathways in tissues. ARBs also block the angiotensin II-induced feedback regulation of renin release, resulting in an increase in angiotensin II levels. With the AT1 receptor blocked, angiotensin II is available to activate the angiotensin type 2 (AT2) receptor, which mediates several potentially beneficial effects in the cardiovascular system, including vasodilation, antiproliferation, and apoptosis. Thus, ARBs provide a highly selective approach for regulating the effects of angiotensin II.
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PMID:Angiotensin II receptor blockers: review of the binding characteristics. 1058 88


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