Blood vessels最新文献

{"title":"Exercise-induced variations in muscle tissue oxygen pressure in claudicants: effects of buflomedil.","authors":"A M Ehrly,&nbsp;K Saeger-Lorenz","doi":"10.1159/000158917","DOIUrl":"https://doi.org/10.1159/000158917","url":null,"abstract":"<p><p>The amount of oxygen actually supplied to the ischemic muscle tissue of patients with intermittent claudication was quantified before and after a standardized pedal ergometric test. Muscle tissue pO2 was measured with micro-platin needle electrodes directly in the lower limb muscles at rest and 3, 10, 20 and 60 min after a 4-min work load. Time-dependent variations in the behavior of pO2 values as well as changes in the shapes of pooled pO2 histograms make it possible to monitor the effect of therapeutic measures. In claudicants (stage IIb) with ascertained occlusions or stenosis of the femoral artery or the pelvis region, it was demonstrated that the delayed increase in tissue pO2 after exercise could be improved by the infusion of 400 mg buflomedil. Comparison between the time-related pooled histograms confirmed improvement of oxygen supply under the influence of this drug.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 Suppl 1 ","pages":"27-32"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158917","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13091254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodological approaches used for the study of the coronary microcirculation in situ.","authors":"W M Chilian,&nbsp;D V DeFily","doi":"10.1159/000158868","DOIUrl":"https://doi.org/10.1159/000158868","url":null,"abstract":"<p><p>Measurements of coronary microvascular parameters in situ are difficult because of the thickness of the heart muscle and cardiac contraction. Both of these problems hamper the visualization of the coronary microcirculation. We have refined methodological approaches that enable the study of the coronary microcirculation in situ. In the first approach, microvessels can be visualized in the beating heart using a preparation that compensates for cardiac motion by creating an illusion that the heart is motionless. This is accomplished by flashing a stroboscopic light source once per heart cycle at the same point in each cycle and synchronizing a ventilator with the cardiac cycle. Images of microvessels can be obtained using standard intravital video-microscopic techniques. To visualize the intramural and subendocardial microcirculation, studies are completed in isolated hearts. In this preparation, measurements of microvascular diameters and pressures can be performed in both the subepicardial and subendocardial microcirculations. This latter approach allows insight into transmural differences of coronary microvascular regulation.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 1-3","pages":"236-44"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158868","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13159382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innervation and effects of dilatory neuropeptides on cerebral vessels. New aspects.","authors":"L Edvinsson","doi":"10.1159/000158841","DOIUrl":"https://doi.org/10.1159/000158841","url":null,"abstract":"<p><p>The cerebral circulation is supplied with two vasodilator systems: the parasympathetic system storing vasoactive intestinal peptide, peptide histidine isoleucine, acetylcholine and in a subpopulation of nerves neuropeptide Y, and the sensory system, mainly originating in the trigeminal ganglion, storing substance P, neurokinin A and calcitonin gene-related peptide (CGRP). Recent knowledge of the innervation and effects of the dilator neuropeptides in the cerebral circulation is reviewed. Their role in the pathophysiology of subarachnoid hemorrhage and migraine has now received attention, with documentation of a clear linkage with the release of CGRP. In subarachnoid hemorrhage, other perivascular peptides are, to a lesser extent, involved.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 1-3","pages":"35-45"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158841","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13159385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of age on rabbit aortic responses to relaxant endothelium-dependent and endothelium-independent agents.","authors":"A Chinellato,&nbsp;L Pandolfo,&nbsp;E Ragazzi,&nbsp;M R Zambonin,&nbsp;G Froldi,&nbsp;M De Biasi,&nbsp;L Caparrotta,&nbsp;G Fassina","doi":"10.1159/000158882","DOIUrl":"https://doi.org/10.1159/000158882","url":null,"abstract":"The aim of this study was to evaluate the effects of aging on endothelium-dependent and endothelium-independent relaxation of rabbit thoracic aorta from New Zealand white rabbits aged 4-6 and 7-12 months. The contractile response to noradrenaline (NA) decreased with increasing age, but NA [EC50] did not vary significantly. Acetylcholine (Ach)-induced relaxation of aortic rings precontracted with NA [EC50] did not change significantly with increasing age. The relaxation induced by ATP of aortic rings, precontracted with NA [EC50], was significantly greater in young than in adult rabbits. This difference between young and adult animals became more evident in aortic rings deprived of endothelium: in adult animals, the ATP-induced relaxation of aortic rings with endothelium was significantly greater than in the rings without endothelium. The endothelium-independent relaxation by sodium nitrite (NaNO2) at lower concentrations was significantly greater in young than in adult rabbit aortic rings precontracted with NA [EC50]. Concluding, the age-induced changes in vascular response in male New Zealand white rabbits are related to an impaired mechanism at smooth muscle level.","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 5","pages":"358-65"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158882","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13071550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of collaterals in the cerebral circulation.","authors":"P Coyle,&nbsp;D D Heistad","doi":"10.1159/000158860","DOIUrl":"https://doi.org/10.1159/000158860","url":null,"abstract":"<p><p>Sudden occlusion of the middle cerebral artery (MCA) in normotensive rats increases blood flow through anastomosing branches into the territory of the occluded artery. Three weeks after MCA occlusion, anastomoses to anterior cerebral branches are increased by more than 50% in luminal diameter. One month after MCA occlusion, blood flow and blood flow reserve to the territory of the occluded MCA are returned to normal levels. In stroke-prone spontaneously hypertensive rats (SHRSP), the anastomoses are significantly narrower and blood flow through the anastomoses is less than in normotensive rats. Tissue infarction invariably develops in the territory of the occluded MCA in SHRSP. We propose that the luminal width of the anastomosis is a major determinant of blood flow into the territory of the occluded artery and of the amount of tissue protected from infarction by collateral circulation.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 1-3","pages":"183-9"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158860","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13157295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of the local renin-angiotensin system in the autoregulation of the cerebral circulation.","authors":"O B Paulson,&nbsp;G Waldemar","doi":"10.1159/000158867","DOIUrl":"https://doi.org/10.1159/000158867","url":null,"abstract":"<p><p>Inhibition of angiotensin-converting enzyme (ACE) shifts the limits of cerebral blood flow autoregulation toward lower blood pressure values. This effect seems to be mediated by blocking the formation of angiotensin II on the luminal side of the larger cerebral resistance vessels. Baseline cerebral blood flow (the flow within the autoregulatory limits) is not changed by acute or chronic ACE inhibition. An interaction between the vascular reninangiotensin and the sympathetic nervous system is present. Activation of the latter inhibits the downwards shift of the upper limit of autoregulation following ACE inhibition.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 1-3","pages":"231-5"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158867","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13159381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L-arginine does not restore endothelial dysfunction in atherosclerotic rabbit aorta in vitro.","authors":"A Mügge,&nbsp;D G Harrison","doi":"10.1159/000158881","DOIUrl":"https://doi.org/10.1159/000158881","url":null,"abstract":"<p><p>Bioassay studies suggest that impaired endothelium-dependent relaxation in atherosclerotic arteries is due to a reduced release of biologically active endothelium-derived relaxing factor (EDRF). We tested the hypothesis that endothelial dysfunction is caused by deficiency of the EDRF precursor L-arginine. Aortae from normal and cholesterol-fed (1%, 4 months) rabbits were excised and incubated for 1 h with 5 mM L-arginine. Pretreatment with L-arginine had no effect on the relaxation to acetylcholine in normal vessels and was without effect on the impaired response of atherosclerotic arteries to acetylcholine. This finding suggests that L-arginine deficiency is unlikely the underlying cause of impaired endothelium-dependent relaxation in the aorta of cholesterol-fed rabbits.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 5","pages":"354-7"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158881","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13071549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is there a role for the vascular renin-angiotensin system in the determination of vascular structure?","authors":"M J Mulvany","doi":"10.1159/000158866","DOIUrl":"https://doi.org/10.1159/000158866","url":null,"abstract":"<p><p>This paper reviews previous work done by my laboratory to investigate the effect of treatment with angiotensin-converting enzyme (ACE) inhibitors on blood pressure and small artery structure in spontaneously hypertensive rats (SHRs). First, the data confirm that ACE inhibitors have a persistent effect on blood pressure in SHRs when treatment is withdrawn. The effect of the ACE inhibitors was dose-dependent, but the persistent effect was not dose-dependent. This suggests that the persistent effect of ACE inhibitors on blood pressure in SHRs is not mediated through vascular structure. Secondly, the data demonstrate that, although ACE inhibitors have dose-dependent effects on both blood pressure and vascular structure, in experiments where different drugs were used, the effect of ACE inhibitors on vascular structure seems to be explained primarily through their effect on blood pressure, rather than any specific drugs effect.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 1-3","pages":"224-30"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158866","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13159380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intracellular pH measurement with fluorescent dye in canine basilar arteries.","authors":"J Yu,&nbsp;J J Zheng,&nbsp;B Y Ong,&nbsp;R Bose","doi":"10.1159/000158893","DOIUrl":"https://doi.org/10.1159/000158893","url":null,"abstract":"<p><p>The intracellular pH (pHi) of basilar artery rings was determined with 2',7'-bis-(carboxyethyl)-5,(6)-carboxyfluorescein (BCECF) by measuring the ratio of emitted (540 nm) fluorescence intensities (FI) at excitation wavelengths of 500 and 440 nm. There was a dye loss from the rings in 90 min (39.3 +/- 3.6%, p less than 0.001). We found that the ratio of fluorescence intensities does not adequately correct for dye loss; hence, we derived a method to correct for dye loss during pHi determinations. Calibration curves of the ratio versus pHi were constructed for the artery rings. The slope and intercept of the calibration curves depended on FI440. Linear regression lines for the slope and intercept versus FI440 were: [formula; see text] In solutions with different pH and different concentrations of free BCECF, the slope of the ratio versus pH of the solution was steeper at high concentrations of BCECF. Thus, pHi was calculated from a calibration curve in which the slope and intercept were determined from FI440 with the above formula. The corrected pHi was 7.37 +/- 0.05 (n = 25) at pHo 7.4 and 37 degrees C.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 6","pages":"464-74"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158893","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12945870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphometric analysis of monkey cerebral arteries exposed in vivo to whole blood, oxyhemoglobin, methemoglobin, and bilirubin.","authors":"R L Macdonald,&nbsp;B K Weir,&nbsp;M G Grace,&nbsp;T P Martin,&nbsp;M Doi,&nbsp;D A Cook","doi":"10.1159/000158896","DOIUrl":"https://doi.org/10.1159/000158896","url":null,"abstract":"<p><p>Whether vasospasm results from smooth muscle contraction or from arterial wall infiltration by cells and other material is subject to debate. Computer-assisted image analysis was used to measure lumen area, total wall area, and area of tunica media plus tunica intima of cross-sections of monkey right middle cerebral arteries (MCAs), exposed in vivo for 6 days to whole blood (n = 4), oxyhemoglobin (OxyHb, n = 5), methemoglobin (MetHb, n = 5), bilirubin (n = 5), mock cerebrospinal fluid (CSF, n = 6), and supernatant fluid from an incubated mixture of autologous blood and mock CSF (n = 5). Five control (left) MCAs from each group and 4 MCAs contracted in vitro with potassium chloride were measured. Significant angiographic vasospasm occurred in groups receiving whole blood, supernatant fluid, and OxyHb (p less than 0.05). There was significant correlation (r = 0.58, p less than 0.05) between right MCA diameter on angiography and diameter calculated from lumen area. When compared to effects of mock CSF, OxyHb significantly increased total wall area. When right and left MCAs were compared within groups, total wall area increased in every group with significant increases in groups exposed to mock CSF, OxyHb, and bilirubin (p less than 0.05). No changes developed in area of tunica media plus tunica intima, whether comparing right versus left MCAs within groups or right MCAs between groups. Contraction in vitro did not significantly increase total wall area or area of tunica media plus tunica intima. Light microscopy demonstrated inflammatory debris in the tunica adventitia of arteries from every group. This study shows that whole blood, OxyHb, and supernatant fluid, which contains OxyHb, cause vasospasm. Increases in total wall area are not sufficient to account for luminal narrowing, and therefore, changes such as cell proliferation and arterial wall fibrosis in the intima or media apparently do not contribute primarily to arterial narrowing of vasospasm but could be related to persistence of narrowing. Vessel wall thickening, which does occur, is caused by increased tunica adventitia area only and is nonspecific in that it develops after injection of substances not associated with vasospasm. The data are consistent with the hypothesis that oxyHb causes vasospasm (both angiographic and morphologic) by inducing muscle contraction in the media.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":"28 6","pages":"498-510"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158896","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12944476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}