Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027497 (nausea)
 23,468 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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 inhibition of 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, diaphoresis, and restlessness. In hypertensive patients blood-pressure responses are complex and are influenced to some extent by renin secretion. PGI2 stimulates renin secretion by a direct effect on the juxtaglomerular apparatus, and it 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 large 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 greatly reduced. Some drugs (thiazides, propranolol) have been shown to stimulate PGI2 synthesis, and inhibition of cyclooxygenase has been shown to reduce their antihypertensive effects. The effects of low- and high-dose aspirin on prostacyclin and thromboxane synthesis are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Prostacyclin in hypertension]. 149 51

Severe pain at rest is a major symptom of advanced peripheral arterial occlusive disease (PAOD). Preliminary studies of treatment with iloprost, a prostacyclin analogue, showed encouraging results in patients with ischaemic rest pain. Therefore a randomized, placebo-controlled multicentre study was undertaken in 113 patients admitted to hospital with rest pain of at least 2 weeks duration caused by severe PAOD. The patients were randomly assigned to receive 2-week placebo or iloprost infusions for 6 hours per day at a dose of 0.5-0.2 ng/kg/min in addition to conventional care. Demographic data and arteriographic findings were similar in the two groups. Eleven patients withdrew from the study before completion and 102 patients could be included in the final analysis. Significantly more patients in the iloprost group (62.5% of 48) than in the placebo group (42.6% of 54) had complete relief of pain without analgesic therapy during at least five consecutive days at the end of the treatment period (p less than 0.05, chi 2-test). Facial flush, headache and nausea were the most common side effects during iloprost infusion. Serious adverse reactions did not occur. Thus, a 2-week iloprost infusion was shown to be safe and effective as a treatment for ischaemic rest pain caused by PAOD.
 ...
PMID:Reduction of ischaemic rest pain in advanced peripheral arterial occlusive disease. A double blind placebo controlled trial with iloprost. 172 69

The investigators conducted a clinical study on antithrombotic effectiveness in ischemic stroke at Siriraj Hospital Medical School, Mahidol University from May 1987 to May 1989. Twenty-nine patients, 16 males and 13 females were enrolled in the study. The ages of the patients ranged from 30-87 years with a mean age of 63 +/- 11 years. Ticlopidine (250 mg) could significantly inhibit platelet aggregation induced by ADP and collagen within 24 hours of drug administration. After 1 week to 6 months, only aggregation by ADP was still inhibited significantly without significant effects on fibrinolytic activity and prostacyclin. Hematocrit was significantly decreased at the 1st and 2nd month of treatment. Serious side effects were skin rash and severe headache while the other common ones were dizziness, and diarrhea but these effects disappeared without discontinuing the drug. Most patients who suffered from nausea, diarrhea and headache, had temporary elevated SGPT. It may be concluded that only half of the recommended dose of ticlopidine has inhibitory effects on both phases of ADP-induced aggregation without interfering with fibrinolytic activity and can maintain prostacyclin. However, it also possesses either serious or common side-effects. This drug, therefore, should be used with the awareness of the clinician.
 ...
PMID:Clinical study on antithrombotic effects of ticlopidine in ischemic stroke. 174 38

Health practitioners use many methods and agents to bring on cervical ripening in early pregnancy, such as intracervical tents and pharmacological techniques, to induce a therapeutic abortion. Prostaglandins alter myometrial and cervical tissue and are the most often used pharmacological technique. Reduced collagen concentration, an increase in water volume, an increase in prostaglandins (PGE2, PGI2, and PGF2 alpha), and a change in the glycosaminoglycan (GAG) content coincide with cervical ripening, yet the mechanism responsible for these changes is obscure. Prostaglandins appear to cause the breakdown of collagen or change the GAG/proteoglycan content. Research shows that prostaglandins can initiate cervical ripening at any stage of pregnancy. Estradiol stimulates prostaglandin production thereby al so inducing cervical dilation. Relaxin also demonstrates an ability to ripen the cervix. In addition, mifepristone (RU-486) is gaining acceptance as a cervical ripening agent. In fact, RU-486 and gemeprost have at least 95% success rate compared to 92% for gemeprost alone or 85% with RU-486 alone. The only effective and acceptable prostaglandins to use at gestation of 0-8 weeks are sulprostone, gemeprost, and 9-methylene-PGE2. At t his gestational age, pharmacological modulation is all that is needed. Even though they are effective (abortion rate 90%), side effects are expected to occur (pain, nausea, and vomiting). Similarly, prostaglandin analogues are preferable for cervical ripening in women at 8-12 weeks gestation. Suction curettage or other surgical techniques then are used to remove the conceptus. At 12-16 weeks gestation, many physicians prefer the same protocol as that of 8-12 weeks gestation. Other choose to infuse PGE2 and saline into the amniotic fluid to stimulate uterine contractions. Another procedure at 12-16 weeks involves 1mg vaginal pessaries of gemeprost every 3 hours to ripen the cervix and stimulate contractions. After 16 weeks, the methods for 12-16 weeks still apply.
 ...
PMID:Pharmacological modulation of cervical compliance in the first and second trimesters of pregnancy. 187 72

This randomized, double-blind study investigated the effect of ciprostene, a stable epoprostenol (prostacyclin) analog in patients with peripheral vascular disease (PVD) characterized by ischemic ulcers. A total of 211 patients (106 ciprostene, 105 placebo) received IV infusions of ciprostene (120 ng/kg/min in 8-hour daily infusions for 7 days) or placebo. The two groups were comparable with regard to demographic data. Only 45% of the patients receiving ciprostene and 55% of the placebo patients completed the trial. The groups were similar in frequency of amputations, vascular surgery, and development of new ulcers. Among those who completed the trials an insignificantly higher percentage of patients receiving ciprostene had all ulcers heal completely. The reduction of ulcer size by at least 50% was higher in the ciprostene-treated group at month 4 (P = .005). Both ciprostene and placebo reduced the severity of a patient's rest pain. There was no difference in the ankle brachial index between the groups. Ciprostene induced a higher incidence of headache, nausea, and flushing during infusion when compared with the placebo group. The results confirmed inherent problems with studies in PVD, namely, scarcity of patients with ischemic ulcers, inclusion of severely ill patients leading to a high dropout rate, and a high placebo effect. Good tolerance and safety of ciprostene was documented in this patient population, and the therapeutic benefit was limited to partial reduction of ulcer size. Selection of patients with less advanced disease and a longer infusion of ciprostene may improve the clinical benefit of this agent.
 ...
PMID:The effect of ciprostene in patients with peripheral vascular disease (PVD) characterized by ischemic ulcers. The Ciprostene Study Group. 204 33

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.
 ...
PMID:Prostacyclin in hypertension. 225 88

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.
 ...
PMID:Infusion of iloprost, a prostacyclin analogue, for treatment of Raynaud's phenomenon in systemic sclerosis. 244 71

The effectiveness of iloprost, a prostacyclin derivative, was assessed in a placebo-controlled multicentre trial on 101 patients with chronic arterial disease, stage IV. All patients were on a basic local treatment, 53 randomly being assigned to the iloprost group, 48 to the placebo one. Both groups received identical saline infusions, one with the other without iloprost. Infusions were given on 28 consecutive days, iloprost being added at a dose of up to 2 ng/kg.min over six hours. At the end of the treatment period, 32 of 52 patients (61.5%) of the iloprost group and eight of the 47 in the placebo group (17%) had partial or complete healing of ulcers (P less than 0.05), the treatment effect persisting in both groups for a mean duration of at least one year. Iloprost was well tolerated, once individual dosages had been appropriately adjusted. Facial flushes, headache and nausea were the most common side effects. Heart rate and blood-pressure variations did not differ between the two groups.
 ...
PMID:[Iloprost, a stable prostacyclin derivative, in stage 4 arterial occlusive disease. A placebo-controlled multicenter study]. 247 May 69

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)
 ...
PMID:Tolerance and pharmacology of ciprostene, a stable epoprostenol (prostacyclin) analogue in humans. 300 77

Although the exposure of human subjects to prostacyclin (PGI2) infusion has been broad, no systematic approaches have been made in order to investigate the dose-related side effects in patients with angina pectoris and coronary artery disease (CAD). We studied 25 patients with typical chest pain and overt CAD. All patients underwent a cycloergometer stress testing (25 W increments at 2-min intervals). PGI2 was infused in scalar doses up to 10 ng/kg/min. During the infusion 25 patients (100%) had facial flushing, 7 (28%) moderate headache and one (4%) had nausea. In addition, 4 patients experienced the typical chest pain and had significant (greater than or equal to 0.1 mV) ST segment depression at 8.10 ng/kg/min infusion rates. These patients had lower tolerance to exercise (6.7 +/- 1.7 vs. 8.8 +/- 1.9 min; p less than 0.05) and coronary artery lesions more severe than those observed in patients without drug-induced angina pectoris. Our data therefore indicate that PGI2 at therapeutic doses may induce myocardial ischemia in patients with angina pectoris, low tolerance to exercise and severe CAD. In patients with mild to moderate degree of CAD, PGI2 was found to be well tolerated. These findings suggest that patients with angina pectoris and low tolerance to exercise should be excluded from clinical studies directed at elucidating the effectiveness of PGI2 in cardiovascular disorders.
 ...
PMID:Side effects of prostacyclin in patients with angina pectoris and coronary artery disease. 390 57


1 2 3 4 Next >>