Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The blood flow in the skin and the urinary excretion of the PGI2 metabolite 2,3-dinor-6-keto-PGF1a (PGI-M) were determined in the nine healthy subjects randomly assigned to double-blind oral treatment with a) placebo and acipimox (AC) 500 mg, b) acetylsalicylic acid 1500 mg and AC 500 mg, or c) placebo and nicotinic acid (NIC) 500 mg, on three different occasions. After treatment with placebo and AC there was a transient increase in the skin blood flow, up to about four-times the basal level, and a concomitant increase in skin temperature. After acetylsalicylic acid and AC no increase in skin flow rate or temperature was found. Urinary excretion of PGI-M was insignificantly increased by AC, but fell after acetylsalicylic acid pretreatment. NIC elicited a more marked increase in skin blood flow than AC, and in parallel the urinary excretion of PGI-M was more than doubled. It is concluded that cutaneous flushing induced by AC is cyclo-oxygenase dependent. In comparison to NIC, however, AC appears as a weak stimulant of vascular prostacyclin formation.
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PMID:Acipimox stimulates skin blood flow by a cyclo-oxygenase-dependent mechanism. 212 38

Prostacyclin (PGI2) is known to cause vasorelaxation and inhibit platelet aggregation by receptor-mediated mechanisms. While cyclic (c)AMP is known to act as a second messenger for platelet aggregation, vasorelaxation by hyperpolarization has been described only recently and may provide an explanation, in addition to stimulation of cAMP, for the PGI2 mechanism of action on blood vessels. When PGI2 is infused into healthy volunteers it reduces blood pressure only at infusion rates that also cause significant side effects, primarily nausea, emesis, flushing, diphoresis and restlessness. In hypertensive patients blood pressure responses are complex and are influenced to some extent by secretion. PGI2 stimulates renin secretion by a direct effect on the juxtaglomerular apparatus, and also has an indirect effect by activating the sympathetic nervous system. Thus it is useless as an antihypertensive agent even apart from its debilitating side effects. Vascular PGI2 is synthesized endogenously by both the endothelial cells and the muscularis of arteries. While the endothelial cells undoubtedly synthesize larger amounts of PGI2, the muscularis comprises a much larger tissue mass so that the overall synthesis is about equally distributed between the endothelial and muscle cells. In patients with pregnancy-induced hypertension and some patients with essential hypertension, endogenous synthesis of PGI2 has been evaluated by measuring 2,3-dinor-6-keto-PGF1 alpha and has proved to be defective. Some drugs (cicletanine, thiazides, propranolol) have been shown to stimulate PGI2 synthesis, and inhibition of cyclooxygenase has been shown to abolish their antihypertensive effects. Whether stimulation of PGI2 synthesis affects the antihypertensive efficacy of these drugs is not yet known.
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PMID:Prostacyclin in hypertension. 225 88

Vasodilators of resistive vessels may induce ischemia in patients with coronary artery disease. To evaluate this possibility during prostacyclin (PGI2; scalar doses up to 10 ng/kg/min) and prostacyclin analog (iloprost; scalar doses up to 6 ng/kg/min) infusions, we studied 33 patients with angina pectoris and proved coronary artery disease. Patients were also submitted to dipyridamole (0.15 mg/kg/min for 4 minutes) and exercise stress testing (starting at 25 W and increasing 25 W every 2 minutes). In a preliminary study the hemodynamic and side effects of iloprost were studied in seven healthy subjects. At an iloprost dose of 4 to 6 ng/kg/min, these subjects had a significant decrease in mean arterial pressure and total peripheral and pulmonary vascular resistances. Side effects were limited to facial flushing and slight headache and were readily reversible. PGI2 induced typical chest pain and significant ST segment depression in six patients with severe coronary artery disease (three with left main and three with triple vessel disease) and poor exercise tolerance (means +/- SD = 362 +/- 99 seconds). All six patients had had angina during the dipyridamole infusion. Similar findings were observed after iloprost infusion in four of these. Aminophylline (125 mg iv) completely relieved chest pain. Although the rate-pressure products occasionally rose during PGI2 and iloprost infusions, there were no significant changes between ischemic (11.3 +/- 2.3 and 10.6 +/- 1.4 X 10(-3) U) and preischemic (10.8 +/- 1.5 and 10.7 +/- 1.4 X 10(-3) U) rates of infusion. Our data indicate that PGI2 and iloprost may induce ischemia independently of changes in oxygen demand, and suggest that these drugs dilate small coronary vessels. This may result in decreased subendocardial perfusion pressure and/or "coronary steal."
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PMID:Myocardial ischemia induced by prostacyclin and iloprost. 240 9

We have recently shown that the novel neuropeptide calcitonin gene-related peptide, CGRP, is a potent vasodilator. In this paper we report a detailed study of the effects of CGRP in human skin. CGRP induces a clearly defined, long-lasting erythema. We have measured the effect of CGRP on blood flow in human skin using a laser Doppler technique and have demonstrated increased local blood flow that persists for a number of hours. We compared the response of CGRP with other known vasodilators [histamine, prostaglandin (PG) E2, PGI2, substance P, and vasoactive intestinal peptide (VIP)] in the skin, and in all subjects the erythema induced by CGRP was more persistent than that induced by the other mediators tested. Except at high doses the local vasodilatation induced by CGRP was not associated with a wheal and flare as seen with histamine, substance P, and VIP. CGRP is an extremely potent vasodilator and if released into the circulation, or locally from peripheral nerve endings, it could have a role in the regulation of blood flow in both physiologic and pathologic conditions; CGRP may be the endogenous mediator of the flare in the triple response. A deficiency in CGRP secretion or action could be an important component of peripheral vascular disease. Some flushing reactions (e.g., those associated with medullary thyroid carcinoma) may result from circulating CGRP.
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PMID:Potent vasodilator activity of calcitonin gene-related peptide in human skin. 242 85

Iloprost, a stable prostacyclin analogue, was given by intravenous infusion to 29 patients with severe Raynaud's phenomenon, 26 of whom had systemic sclerosis (SS), and compared with placebo infusion in a double blind crossover trial. Iloprost significantly lessened the number and the severity of attacks compared with placebo. Nine patients expressed a preference for effectiveness of treatment, eight of these in favour of Iloprost. Thermography failed to show any long term effect of Iloprost. Side effects of headache, flushing, nausea, and vomiting were common, and the inconvenience of intravenous administration may limit its routine use.
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PMID:Infusion of iloprost, a prostacyclin analogue, for treatment of Raynaud's phenomenon in systemic sclerosis. 244 71

Prostacyclin (PGI2) has proven beneficial effects on organ preservation. Iloprost (ZK 36 374), a stable synthetic analogue with a longer half-life of 14 minutes is reported to have less hypotensive effects than PGI2 while offering increased cytoprotective and antiaggregation action. In this study its effects on lung-preservation were investigated. The heart lung block of 12 Beagle dogs was harvested after flushing of the pulmonary artery with 60 ml/kg modified Eurocollins (MEC) solution, the left lung was stored for 4 hours and then transplanted into 12 weight-matched dogs. Prior to operation the animals were randomized into two groups with MEC solution as the only preservative in group A and an additional i.v. infusion of 1 microgram/kg/min Iloprost during 15 minutes prior to flushing and 15 micrograms/kg Iloprost administered to the perfusate in group B. Arterial pO2, alveolo-arterial oxygen difference (AaDO2) and pulmonary artery pressure (PAP) of the transplanted lungs were measured 1, 4, 12, and 24 hours after transplantation during occlusion of the contralateral pulmonal artery. The application of Iloprost resulted in a significant improvement of pO2 (p = 0.047), AaDO2 (p = 0.002) and PAP (p = 0.018) after 1 hour. Results in group B at later time points were improved without reaching statistical significance. Iloprost therefore showed beneficial effects on pulmonary function early after lung preservation with MEC.
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PMID:Beneficial effect of iloprost on early pulmonary function after lung preservation with modified eurocollins solution. 247 70

Nicotinic acid (niacin) is a B vitamin which is also a potent hypolipidemic agent. However, intense flushing occurs following ingestion of pharmacologic doses of niacin which greatly limits its usefulness in treating hyperlipidemias. Previous studies have demonstrated that niacin-induced flushing can be substantially attenuated by pre-treatment with cyclooxygenase inhibitors, suggesting that the vasodilation is mediated by a prostaglandin. However, the prostaglandin that presumably mediates the flush has not been conclusively determined. In this study we report the finding that ingestion of niacin evokes the release of markedly increased quantities of PGD2 in vivo in humans. PGD2 release was assessed by quantification of the PGD2 metabolite, 9 alpha, 11 beta-PGF2, in plasma by gas chromatography mass spectrometry. Following ingestion of 500 mg of niacin in three normal volunteers, intense flushing occurred and plasma levels of 9 alpha, 11 beta-PGF2 were found to increase dramatically by 800, 430, and 535-fold. Levels of 9 alpha, 11 beta-PGF2 reached a maximum between 12 and 45 min. after ingesting niacin and subsequently declined to near normal levels by 2-4 hours. Levels of 9 alpha, 11 beta-PGF2 in plasma correlated with the intensity and duration of flushing that occurred in the 3 volunteers. Release of PGD2 was not accompanied by a release of histamine which was assessed by quantification of plasma levels of the histamine metabolite, N tau-methylhistamine. This suggests that the origin of the PGD2 release is not the mast cell. Only a modest increase (approximately 2-fold) in the urinary excretion of the prostacyclin metabolite, 2,3-dinor-6-keto-PGF1 alpha, occurred following ingestion of niacin and no increase in the excretion of the major urinary metabolite of PGE2 was found. These results indicate that the major vasodilatory PG released following ingestion of niacin is PGD2. The fact that markedly increased quantities of PGD2 are released suggests that PGD2 is the mediator of niacin-induced vasodilation in humans.
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PMID:Release of markedly increased quantities of prostaglandin D2 in vivo in humans following the administration of nicotinic acid. 247 89

The effects of intravenous infusion of three vasodilators on skin blood flow were studied in eight patients with Raynaud's phenomenon and eight controls, matched for age and sex, by means of the non-invasive technique of laser doppler flowmetry (LDF). The responses to calcitonin-gene-related peptide (CGRP) were compared with those to the endothelium-dependent vasodilator adenosine triphosphate (ATP) and the endothelium-independent vasodilator prostacyclin (epoprostenol; PGI2). In the patients with Raynaud's phenomenon, CGRP induced flushing of the face and hands accompanied by a rise in skin blood flow, whereas in the controls CGRP caused flushing and increased blood flow only in the face. PGI2 caused similar rises in skin blood flow in the hands and face in both groups. ATP did not cause any significant changes in skin blood flow in the face or hands in the patients, but in the controls it increased skin blood flow in the face. Since the suprasensitivity to CGRP of skin blood flow in the hands of patients with Raynaud's phenomenon is not common to other vasodilators, it may reflect a deficiency of endogenous CGRP release in this disorder.
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PMID:Selective suprasensitivity to calcitonin-gene-related peptide in the hands in Raynaud's phenomenon. 196 14

Safety, tolerance, and pharmacology of 9-beta-methylcarbacyclin calcium (ciprostene calcium) was investigated in healthy male volunteers. This stable prostacyclin analogue was infused intravenously into groups of 12, 11, and three volunteers for three, six, and eight hours, respectively, in doses up to 480 ng/kg/min. Based on the tolerance data obtained, a single-blind, placebo-controlled study was conducted. Seven subjects were infused for 8 hr/d for three days with ciprostene at a maximum dose of 160 ng/kg/min and seven subjects received placebo. One subject from each group did not complete the infusion schedule, and they were not included in the final analysis. During infusion of ciprostene, consistent changes in blood pressure and heart rate did not occur. Most frequent adverse drug reactions consisted of headache, restlessness, nausea, perspiration, flushing, and jaw pain. As compared with placebo, ADP-induced platelet aggregation was inhibited during the infusion period (P = .048). Significant (P = .04) elevations of platelet cyclic AMP were observed in subjects during infusion of ciprostene. Pre- versus postinfusion routine laboratory evaluations, fibrinogen concentration, antiplasmin activity, and plasminogen and template bleeding times remained unchanged. Placebo- and drug-treated subjects had a daily postinfusion shortening of euglobulin clot lysis time (ECLT). The preinfusion minus postinfusion ECLT for ciprostene subjects on days 2 and 3 (133 and 118 min, respectively) compared with placebo (239 and 217 min) suggest a trend to increased fibrinolytic activity. Based on the outcome of this trial, it is estimated that ciprostene is about 15 times less potent than prostacyclin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Tolerance and pharmacology of ciprostene, a stable epoprostenol (prostacyclin) analogue in humans. 300 77

Epoprostenol (Prostacyclin) has been studied with various success in patients with peripheral vascular disease (PVD). We investigated the tolerance of a new, stable prostacyclin derivative ciprostene (9-beta-methyl carbacyclin) in 9 PVD patients. The drug was infused intravenously for 8 hours a day, once a week for 4 consecutive weeks, at a dose of 120 ng/kg/min. There were 6 men and 3 women with a mean age of 63 years (42-78). The PVD was verified by arteriography (9 patients) and by clinical findings. Patient #9 was lost to follow up after the first infusion and, consequently, was excluded from further evaluation. In patient #5 with a history of arrhythmias, the last ciprostene infusion had to be discontinued at 4.5 hours due to arrhythmias but his data were included into the evaluation. The cardiac disturbances were not judged to be ciprostene-related. Patients were followed monthly for 3 months after last infusion. Ciprostene was well tolerated although it produced adverse medical events (AMEs); most of them were rated as mild. The most frequent were those typical of prostacyclin: headache, facial flushing and warmth, body warmth, jaw pain and sleepiness. No consistent changes in blood pressure and heart rate were observed. One patient who initially had 9 ischemic ulcers underwent transmetatarsal amputation at month 4. The absolute and relative claudication time was measured by treadmill. As compared to baseline, the absolute claudication time increased significantly at week 2 and 4 of the infusion period and also at the end of month 3, but not at the end of month 4.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ciprostene in patients with peripheral vascular disease (PVD). An open-label, tolerance trial. 306 80


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