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Vasoactive Substances (vasoactive + substance)
Selected AbstractsOestrogen attenuates coronary vasoconstriction after angioplasty: role of endothelin-1EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2002T-M. Lee Abstract Background and aims There were controversies as to whether endothelin-1 is released after coronary angioplasty. We sought to determine whether endothelin-1 is released after coronary angioplasty and whether oestrogen administration can affect coronary vasomotor tone by reducing endothelin-1 concentrations. Methods The study was designed to prospectively investigate 24 consecutive patients scheduled for elective coronary angioplasty. Patients were randomized into two groups according to whether they did not (group 1, n = 12) or did (group 2, n = 12) have intracoronary treatment with oestrogen. Quantitative coronary angiography was monitored at baseline, immediately after successful angioplasty, and 15 min after the last deflation. Blood samples for measuring the levels of endothelin-1 were drawn from the ascending aorta and the coronary sinus simultaneously before angioplasty and 15 min after balloon dilatation. Results The diameters of the coronary artery at the dilated segments were significantly reduced 15 min after dilation compared with those immediately after dilation in group 1 from 3·20 ± 0·22 to 2·30 ± 0·23 mm (P < 0·001), respectively. The vasoconstriction was significantly blunted in group 2. The endothelin-1 levels from the coronary sinus rose significantly, by 29%, 15 min after angioplasty in group 1, which was attenuated after administering oestrogen. Significant correlation was found between the changes of coronary vasomotion of the dilated segment and endothelin-1 levels (r = 0·70, P = 0·01). Conclusion Endothelin-1 is released into the coronary circulation after angioplasty, and this vasoactive substance may contribute to the occurrence of vasoconstriction. The vasoconstriction is attenuated by oestrogen by reducing the endothelin-1 levels. This finding provided a new strategy to treat coronary vasoconstriction after angioplasty. [source] Severe rosacea associated with colon cancer recurrenceINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2004L. Margolin MD An 80-year-old male, who had undergone orchiectomy because of prostatic cancer, presented with rosacea (for the first time in his life), weight loss and anemia, and was diagnosed with local recurrence of colon cancer. The hormonal disarrangement unbalance after orchiectomy and a paraneoplastic vasoactive substance may have contributed to the development of rosacea in this patient. [source] The effects of acute and chronic exercise on the vasculatureACTA PHYSIOLOGICA, Issue 4 2010J. J. Whyte Abstract Regular physical activity (endurance training, ET) has a strong positive link with cardiovascular health. The aim of this review is to draw together the current knowledge on gene expression in different cell types comprising the vessels of the circulatory system, with special emphasis on the endothelium, and how these gene products interact to influence vascular health. The effect beneficial effects of ET on the endothelium are believed to result from increased vascular shear stress during ET bouts. A number of mechanosensory mechanisms have been elucidated that may contribute to the effects of ET on vascular function, but there are questions regarding interactions among molecular pathways. For instance, increases in flow brought on by ET can reduce circulating levels of viscosity and haemostatic and inflammatory variables that may interact with increased shear stress, releasing vasoactive substances such as nitric oxide and prostacyclin, decreasing permeability to plasma lipoproteins as well as the adhesion of leucocytes. At this time the optimal rate-of-flow and rate-of-change in flow for determining whether anti-atherogenic or pro-atherogenic processes proceed remain unknown. In addition, the impact of haemodynamic variables differs with vessel size and tissue type in which arteries are located. While the hurdles to understanding the mechanism responsible for ET-induced alterations in vascular cell gene expression are significant, they in no way undermine the established benefits of regular physical activity to the cardiovascular system and to general overall health. This review summarizes current understanding of control of vascular cell gene expression by exercise and how these processes lead to improved cardiovascular health. [source] Primary carcinoid tumor of the bilateral testis associated with carcinoid syndromeINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2004HYUN-YOUNG SON Abstract Carcinoid tumors derived from neuroendocrine cells can release serotonin and other vasoactive substances into the systemic circulation, resulting in carcinoid syndrome. Testicular carcinoid, a rare disease accounting for less than 1% of all testicular neoplasms, rarely manifests symptoms of carcinoid syndrome. We describe a case of carcinoid syndrome arising from a primary testicular carcinoid tumor. A 21-year-old male patient presented with facial flushing and diarrhea for 5 years. He had an enlarged left testis and a 1-cm, ill-defined, hard, non-tender mass in his right testis. His 24 h urinary excretion of 5-hydroxyindoleacetic acid was elevated (16.1 mg/day). Somatostatin receptor scintigraphy correlated with carcinoid tumor in both testes. Following bilateral orchiectomy, the patient's facial flushing and diarrhea disappeared. [source] Chronic urticaria , which clinical parameters are pathogenetically relevant?JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 1 2007A retrospective investigation of 339 patients Summary Background: Urticaria is a clinical reaction pattern triggered by many factors causing liberation of vasoactive substances such as histamine, prostaglandins and kinins. It presents as transient itching wheals which are either limited to the local stimulus area or more widespread. Urticaria is classified according to its duration into acute (duration , 6 weeks) and chronic (duration 6 weeks) forms. Various clinical investigations may be initiated to diagnose the cause. This study critically evaluates the relevance of frequently performed laboratory investigations and searches for infectious foci, as well as the results of physical provocation testing and oral provocation with food additives. Patients and Methods: The laboratory and clinical data of 339 patients who had been treated for urticaria at the Christian-Albrechts-University in Kiel over a period of four years were collected in a data entry form and statistically evaluated. Nominal values were analyzed by their relative and absolute quantities, quantitative parameters with the help of statistical data such as minimum, maximum, median and 25th and 75th percentiles. Results: Chronic recurrent urticaria was most common, accounting for 52% of cases. Women were affected 1.8 times more often than men. One-third of the patients also had angioedema. The medians of all laboratory parameters evaluated were within normal values. Only rarely were elevated antinuclear antibody titers, abnormal thyroid function tests or active infections such as hepatitis B or borreliosis detected. The search for infectious foci identified tonsillitis or sinusitis in almost 50% of analyzed patients. Positive reactions to physical testing occurred in 30% of patients and in 11% to oral provocation with various food additives. Conclusions: This study of a large patient group stresses the relevance of individually- tailored evaluations in patients affected with urticaria rather than an expensive initial broad diagnostic testing. More specific searches should be based on individual clues. [source] Ginkgo biloba extract improves coronary artery circulation in patients with coronary artery disease: contribution of plasma nitric oxide and endothelin-1PHYTOTHERAPY RESEARCH, Issue 6 2008Yu-Zhou Wu Abstract In patients with coronary artery disease (CAD), coronary blood flow is usually impaired due to imbalanced vasoactive substances such as nitric oxide (NO) and endothelin-1 (ET-1). The study was designed to test the effects of Ginkgo biloba extract (GBE) on the distal left anterior descending coronary artery (LAD) blood flow and plasma NO and ET-1 levels. Eighty CAD patients were randomly assigned to GBE (n = 42) and control (n = 38) groups. The LAD blood flow was assessed non-invasively using Doppler echocardiography at baseline and after 2 weeks. GBE treatment demonstrated a significant improvement in maximal diastolic peak velocity (MDPV), maximal systolic peak velocity (MSPV) and diastolic time velocity integral (DTVI) compared with controls (14.61 ± 4.51% vs 0.67 ± 2.66%, 9.03 ± 4.81% vs 0.34 ± 2.67% and 14.69 ± 5.08% vs 0.68 ± 3.00%, respectively, p < 0.01). NO was increased by 12.42% (p < 0.01), whereas ET-1 was decreased by 5.82% (p < 0.01). The NO/ET-1 ratio was increased by 19.47% (p < 0.01). A linear correlation was confirmed between the percentage change in LAD blood flow and in NO, ET-1 or NO/ET-1 ratio following GBE treatment. The results suggest that GBE treatment in CAD patients led to an increase of LAD blood flow, which might at least be related partly to the restoration of the delicate equilibrium between NO and ET-1. Copyright © 2008 John Wiley & Sons, Ltd. [source] Local mechanisms for luteolysis in the cow: Novel roles of vasoactive substances in the luteolytic cascade within the corpus luteumANIMAL SCIENCE JOURNAL, Issue 5 2007Koumei SHIRASUNA ABSTRACT The corpus luteum (CL) in the estrous cycle in the cow is a dynamic organ which has a lifespan of approximately 17,18 days. As the CL matures, the steroidogenic cells establish contact with many capillary vessels and the CL is composed of a large number of vascular endothelial cells that can account for up to 50% of the bovine CL. Furthermore, luteal cells and endothelial cells secrete several vasoactive substances such as prostaglandin F2, (PGF2,), endothelin-1 and angiotensin II. These vasoactive substances also function in regulating progesterone secretion in an autocrine/paracrine manner in the CL. The blood vessels and endothelial cells in the CL therefore have an essential role in the luteal function in the cow. Endometrial PGF2,, the primary luteolysin in the cow, stimulates luteal vasoactive substances during luteolysis. Moreover, luteal vasoactive substances may have key roles in the regulation of luteolysis to induce vasodilatation, vasoconstriction and angiolysis. This review describes the current concept for possible roles of vasoactive substances in the luteolytic cascade within the bovine CL. [source] Long-term streptozotocin-induced diabetes alters prostanoid production in rat aorta and mesenteric bedAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 4 2006H. A. Peredo Summary 1 Vascular disease is a major cause of mortality and morbidity in chronic diabetes mellitus. 2 Prostanoids, metabolites of arachidonic acid, include vasoactive substances produced and released from the vascular wall. Alterations in prostanoid production have been reported in the vasculature of diabetic humans and experimental animals. 3 The aim of the present work was to study the influence of three different periods of long-term streptozotocin-induced diabetes, 30, 120 and 180 days in the production of prostanoids in the thoracic aorta and in the mesenteric vascular bed of the rat. The prostanoids released to the incubation medium by the tissues were extracted and measured by reversed-phase HPLC. 4 In the diabetic groups, body weight was reduced and glycaemia was increased when compared with the corresponding non-diabetic controls. 5 In the aorta, 30 days of diabetes did not modify the prostanoid release pattern, meanwhile 120 and 180 days of incubation decreased prostacyclin (PGI2) production. In the mesenteric bed, at 30 days the release of the vasodilators PGI2 and prostaglandin (PGE2) and the vasoconstrictor thromboxane (TXA2) was reduced. At 120 days the vasodilators were reduced and at 180 days such reduction was joined by an increase of the release of vasoconstrictor metabolites. 6 Thirty days of diabetes did not modify the PGI2/TXA2 ratio in the aorta or mesenteric bed. On the other hand, 120 and 180 days of diabetes reduced significantly the ratio when compared with the corresponding controls. 7 In conclusion, the mesenteric bed, a resistance vascular bed, seems to be more sensitive than the aorta, a conductance vessel, to the effects of diabetes on prostanoid production. The observed effects contribute to a displacement of the balance of prostanoid release in favour of the vasoconstrictor metabolites, a phenomenon that could be related to the vascular complications of diabetes mellitus. [source] Oral treatment and in vitro incubation with fructose modify vascular prostanoid production in the ratAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 1 2006H. A. Peredo Summary 1 In the rat, a fructose-enriched diet induces hyperglycaemia, hypertriglyceridaemia, insulin resistance and hypertension; a model which resembles the human metabolic syndrome. 2 Prostanoids, metabolites of arachidonic acid, include vasoactive substances synthesized and released from the vascular wall that have been implicated in the increase of peripheral resistance, one of the mechanisms involved in the fructose-induced hypertension. 3 The aim of the present study was to: (i) analyse the effects of the in vitro incubation with fructose on the production and release of prostanoids in rat thoracic aorta and in rat mesenteric bed and (ii) compare the effects of incubation with those of the in vivo acute and chronic treatment of rats with fructose and with the combination of both in vivo and in vitro procedures. 4 Blood pressure, glycaemia and triglyceridaemia were significantly elevated in both 4- and 22-week fructose-treated groups. Meanwhile, body and heart weight as well as insulinaemia were similar between experimental animals and controls. 5 In aortae, 4 weeks of Fructose treatment did not modify the prostanoid pattern release, but in vitro incubation decreased prostacyclin (PGI2) production. However, after 22 weeks, fructose treatment and incubation exerted the same effect. 6 In mesenteric bed, after 4 weeks, the incubation and the combination of both procedures reduced the release of the vasodilators PGI2 and PGE2, while fructose treatment only diminished the PGE2 release. On the contrary, the production of the vasoconstrictor thromboxane A2 (TXA2) was enhanced by incubation and both the procedures. After 22 weeks, fructose treatment increased PGI2 release, while it was reduced by incubation. The combination of both did not modify this peripheral resistance when compared with controls. Finally, incubation of tissues from treated rats increased the release of the vasoconstrictors, PGF2, and TXA2. 7 In conclusion, the mesenteric bed, a resistance vascular bed, seems to be more sensitive than the aorta, a conductance vessel, to the effects of fructose on prostanoid production. This difference could be related to a more relevant role of resistance vessels in the regulation of peripheral resistance and consequently of blood pressure. The observed effects should contribute to a shift in the balance of the release of prostanoid in favour of vasoconstrictor metabolites. This phenomenon could be related to an increase in the peripheral resistance and the mild hypertension observed in the fructose-treated rats. [source] Forearm blood flow in pre-eclampsiaBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 4 2003Lucy Bowyer Objective 1. To characterise the forearm vascular reactivity of women with pre-eclampsia in the third trimester of pregnancy and compare it with that in normal or gestational hypertensive pregnancies. 2. To document female sex steroid (oestradiol, progesterone, oestriol and ,hCG) levels in the three groups of women. Design Forearm blood flow was measured by venous occlusion plethysmography during intra-arterial infusion of saline and vasoactive substances: angiotensin II, sodium nitroprusside, acetylcholine and NG -monomethyl- l -arginine (l -NMMA). Setting Research laboratory at St George Hospital, Kogarah, Sydney, Australia. Sample Fifteen non-pregnant women in the follicular phase of the menstrual cycle, 15 third trimester normal pregnant women, 13 women in the third trimester with gestational hypertension and 15 women with pre-eclampsia. Main outcome measures Changes in forearm blood flow in response to vasoactive substances. Results Normal pregnant women had higher baseline forearm blood flow than non-pregnant women, decreased vasodilator responses to sodium nitroprusside and reduced vasoconstrictor responses to angiotensin II. No difference in response to angiotensin II, sodium nitroprusside or l -NMMA was found among normal pregnant, pre-eclampsia or gestational hypertension women, but vasodilatory responses of pre-eclamptic women to acetylcholine were reduced compared with normal pregnant women. Higher serum progesterone levels were found in women with pre-eclampsia and gestational hypertension than in normal pregnancy. Conclusion The hyperdynamic circulation of normal pregnancy is characterised by refractoriness to angiotensin II but this is not altered in pre-eclampsia. Pre-eclamptic women demonstrate a reduced vasodilator response to acetylcholine which, in the absence of any alteration in response to l -NMMA, implies that factors other than nitric oxide deficiency mediate the vasoconstriction of pre-eclampsia. [source] | |||||||||||||||||||||||||