Microcirculation最新文献

{"title":"Three-dimensional spatial quantitative analysis of cardiac lymphatics in the mouse heart","authors":"Evan H. Phillips,&nbsp;Vytautas P. Bindokas,&nbsp;Dahee Jung,&nbsp;Jay Teamer,&nbsp;Jan K. Kitajewski,&nbsp;R. John Solaro,&nbsp;Beata M. Wolska,&nbsp;Steve Seung-Young Lee","doi":"10.1111/micc.12826","DOIUrl":"10.1111/micc.12826","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>Three-dimensional (3D) microscopy and image data analysis are necessary for studying the morphology of cardiac lymphatic vessels (LyVs) and their association with other cell types. We aimed to develop a methodology for 3D multiplexed lightsheet microscopy and highly sensitive and quantitative image analysis to identify pathological remodeling in the 3D morphology of LyVs in young adult mouse hearts with familial hypertrophic cardiomyopathy (HCM).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We developed a 3D lightsheet microscopy workflow providing a quick turn-around (as few as 5–6 days), multiplex fluorescence detection, and preservation of LyV structure and epitope markers. Hearts from non-transgenic and transgenic (TG) HCM mice were arrested in diastole, retrograde perfused, immunolabeled, optically cleared, and imaged. We built an image-processing pipeline to quantify LyV morphological parameters at the chamber and branch levels.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Chamber-specific pathological alterations of LyVs were identified, and significant changes were seen in the right atrium (RA). TG hearts had a higher volume percent of ER-TR7⁺ fibroblasts and reticular fibers. In the RA, we found associations between ER-TR7⁺ volume percent and both LyV segment density and median diameter.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This workflow and study enabled multi-scale analysis of pathological changes in cardiac LyVs of young adult mice, inviting ideas for research on LyVs in cardiac disease.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12826","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10498220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Progress in molecular mechanisms of coronary microvascular dysfunction","authors":"Hao Li,&nbsp;Yuping Gao,&nbsp;Yuanyuan Lin","doi":"10.1111/micc.12827","DOIUrl":"10.1111/micc.12827","url":null,"abstract":"<p>Coronary microvascular dysfunction is a high-risk factor for many cardiovascular events. However, because of multiple risk factors and limited understanding about its underlying pathophysiological mechanisms, it was easily misdiagnosed. Therefore, its clinical diagnosis and treatment were greatly restricted. Coronary microcirculation refers to microvessels that play an important role in the physiological regulation of myocardial perfusion and regulating blood flow distribution, fulfilling myocardial metabolic needs and moderating peripheral vascular resistance. In coronary microvascular dysfunction, vascular endothelial celldamage is a critical link. The main feature of early coronary microvascular dysfunction is the impairment of endothelial cell proliferation, adhesion, migration, apoptosis, and secretion. Moreover, coronary microvascular dysfunction risk factors include hyperglycemia, lipid metabolism disorders, ischemia-reperfusion injury, aging, and hypertension, similar to coronary atherosclerosis. There are various mechanisms by which these risk factors harm endothelial function and cause microcirculatory disturbances. Therefore, we reviewed coronary microvascular dysfunction's risk factors and pathogenesis in this article.</p>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10052215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beneficial effects of empagliflozin and liraglutide on the cerebral microcirculation of diabetic rats","authors":"Joana Costa d'Avila,&nbsp;Aluana Santana Carlos,&nbsp;Raimundo Lima Vieira,&nbsp;Carla Vergueiro,&nbsp;Aline Teixeira Lima,&nbsp;Isaias dos Santos Silva,&nbsp;Vivian Carvalho de Figueiredo,&nbsp;Paulo Henrique Petrone Chateaubriand,&nbsp;Adalgiza Mafra Moreno,&nbsp;Hugo Caire de Castro Faria Neto,&nbsp;Vanessa Estato,&nbsp;Rodrigo Azeredo Siqueira","doi":"10.1111/micc.12825","DOIUrl":"10.1111/micc.12825","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>This study aimed to evaluate the effects of the antidiabetics liraglutide, a GLP-1 analog, and empagliflozin, an SGLT-2 inhibitor, on the brain microcirculation of diabetic rats.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Type 2 diabetes mellitus (DM) was experimentally induced in male Wistar rats by combining a high-fat diet and a low dose of streptozotocin (35 mg/kg). Liraglutide (100 μg/kg s.c.) and empagliflozin (10 mg/kg, oral) were administered for 5 weeks. Body weight was monitored periodically. Oral glucose tolerance, fasting glycemia, and blood triglycerides were evaluated after the treatments. Endothelial–leukocyte interactions in the brain microcirculation and structural capillary density were assessed.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>DM rats presented metabolic and cerebrovascular alterations. Liraglutide treatment decreased body weight and blood triglycerides of DM rats. Empagliflozin treatment improved glucose tolerance but only the combination therapy significantly reduced fasting blood glucose. Both treatments and their combination reduced leukocyte adhesion into the endothelium of brain venules. However, empagliflozin was more effective in preventing DM-induced microvascular rarefaction.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>These findings suggest that chronic treatment with SGLT2 inhibitors and GLP-1 receptor agonists may serve as potential therapeutic approaches to prevent microvascular complications associated with diabetes.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9953870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of the endothelial surface layer via hyaluronidase does not modulate monocyte and neutrophil interactions with the glomerular endothelium","authors":"ZheHao Tan,&nbsp;Pam Hall,&nbsp;Adam Costin,&nbsp;Simon A. Crawford,&nbsp;Georg Ramm,&nbsp;Connie H. Y. Wong,&nbsp;A. Richard Kitching,&nbsp;Michael J. Hickey","doi":"10.1111/micc.12823","DOIUrl":"10.1111/micc.12823","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>The endothelial surface layer (ESL), a layer of macromolecules on the surface of endothelial cells, can both impede and facilitate leukocyte recruitment. However, its role in monocyte and neutrophil recruitment in glomerular capillaries is unknown.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We used multiphoton intravital microscopy to examine monocyte and neutrophil behavior in the glomerulus following ESL disruption with hyaluronidase.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Constitutive retention and migration of monocytes and neutrophils within the glomerular microvasculature was unaltered by hyaluronidase. Consistent with this, inhibition of the hyaluronan-binding molecule CD44 also failed to modulate glomerular trafficking of these immune cells. To investigate the contribution of the ESL during acute inflammation, we induced glomerulonephritis via in situ immune complex deposition. This resulted in increases in glomerular retention of monocytes and neutrophils but did not induce marked reduction in the glomerular ESL. Furthermore, hyaluronidase treatment did not modify the prolonged retention of monocytes and neutrophils in the acutely inflamed glomerular microvasculature.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These observations indicate that, despite evidence that the ESL has the capacity to inhibit leukocyte-endothelial cell interactions while also containing adhesive ligands for immune cells, neither of these functions modulate trafficking of monocytes and neutrophils in steady-state or acutely-inflamed glomeruli.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12823","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10234592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microvascular dysfunction in patients with heart failure with preserved ejection fraction: A meta-analysis","authors":"Mai Azuma,&nbsp;Shingo Kato,&nbsp;Kazuki Fukui,&nbsp;Nobuyuki Horita,&nbsp;Daisuke Utsunomiya","doi":"10.1111/micc.12822","DOIUrl":"10.1111/micc.12822","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Although microvascular dysfunction (MVD) is considered an essential pathophysiology in patients with heart failure with preserved ejection fraction (HFpEF), the frequency and prognostic impact of MVD are not fully understood. This meta-analysis evaluated the frequency of MVD in patients with HFpEF and its utility in risk stratification.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and Methods</h3>\u0000 \u0000 <p>On May 26, 2022, a literature search was performed on PubMed, Web of Science, the Cochrane library, and Embase using the search terms such as “Heart failure with preserved ejection fraction,” “HFpEF,” “microvascular dysfunction,” and “MVD.” The prevalence of MVD in patients with HFpEF was calculated using the general inverse variance method. A comprehensive literature review was conducted to examine the association between MVD and prognosis in patients with HFpEF.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Data pertaining to a total of 941 patients diagnosed with HFpEF were extracted from the collective pool of 9 studies. The results of the meta-analysis revealed that the frequency of MVD among patients with HFpEF was found to be 55.5% (95% CI: 34.8%–76.2%), with a substantial degree of heterogeneity (<i>I</i>² = 98%, <i>p</i> for heterogeneity &lt;.001). Among the five studies that provided data on the association between MVD and prognosis, a significant statistical association was observed in four of them.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This meta-analysis revealed that approximately 50% of patients diagnosed with HFpEF exhibited MVD. Moreover, the presence of MVD demonstrated significant prognostic implications in multiple studies conducted on patients with HFpEF. These findings strongly suggest that MVD plays a crucial role in the underlying pathophysiology of patients with HFpEF.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9861917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended-volume image-derived models of coronary microcirculation","authors":"Vibujithan Vigneshwaran,&nbsp;Christine Lauren Sy,&nbsp;Bruce H. Smaill,&nbsp;Gregory B. Sands,&nbsp;Nicolas P. Smith","doi":"10.1111/micc.12820","DOIUrl":"10.1111/micc.12820","url":null,"abstract":"Recent advances in tissue clearing and high‐throughput imaging have enabled the acquisition of extended‐volume microvasculature images at a submicron resolution. The objective of this study was to extract information from this type of images by integrating a sequence of 3D image processing steps on Terabyte scale datasets.","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 5-6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12820","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10342682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The sublingual microcirculation and frailty index in chronic kidney disease patients","authors":"Ryan A. P. Homes,&nbsp;Fiona Giddens,&nbsp;Ross S. Francis,&nbsp;Ruth E. Hubbard,&nbsp;Emily H. Gordon,&nbsp;Mark J. Midwinter","doi":"10.1111/micc.12819","DOIUrl":"10.1111/micc.12819","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>To examine the relationship between sublingual microcirculatory measures and frailty index in those attending a kidney transplant assessment clinic.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Patients recruited had their sublingual microcirculation taken using sidestream dark field videomicroscopy (MicroScan, Micro Vision Medical, Amsterdam, the Netherlands) and their frailty index score using a validated short form via interview.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A total of 44 patients were recruited with two being excluded due to microcirculatory image quality scores exceeding 10. The frailty index score indicated significant correlations with total vessel density (<i>p</i> &lt; .0001, <i>r</i> = −.56), microvascular flow index (<i>p</i> = .004, <i>r</i> = −.43), portion of perfused vessels (<i>p</i> = .0004, <i>r</i> = −.52), heterogeneity index (<i>p</i> = .015, <i>r</i> = .32), and perfused vessel density (<i>p</i> &lt; .0001, <i>r</i> = −.66). No correlation was shown between the frailty index and age (<i>p</i> = .08, <i>r</i> = .27).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>There is a relationship between the frailty index and microcirculatory health in those attending a kidney transplant assessment clinic, that is not confounded by age. These findings suggest that the impaired microcirculation may be an underlying cause of frailty.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 5-6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12819","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9985834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variations in mechanical stiffness alter microvascular sprouting and stability in a PEG hydrogel model of idiopathic pulmonary fibrosis","authors":"Julie Leonard-Duke,&nbsp;Anthony C. Bruce,&nbsp;Shayn M. Peirce,&nbsp;Lakeshia J. Taite","doi":"10.1111/micc.12817","DOIUrl":"10.1111/micc.12817","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>Microvascular remodeling is governed by biomechanical and biochemical cues which are dysregulated in idiopathic pulmonary fibrosis. Understanding how these cues impact endothelial cell-pericyte interactions necessitates a model system in which both variables can be independently and reproducibly modulated. In this study we develop a tunable hydrogel-based angiogenesis assay to study how varying angiogenic growth factors and environmental stiffness affect sprouting and vessel organization.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Lungs harvested from mice were cut into 1 mm long segments then cultured on hydrogels having one of seven possible stiffness and growth factor combinations. Time course, brightfield, and immunofluorescence imaging were used to observe and quantify sprout formation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Our assay was able to support angiogenesis in a comparable manner to Matrigel in soft 2 kPa gels while enabling tunability to study the effects of stiffness on sprout formation. Matrigel and 2 kPa groups contained significantly more samples with sprouts when compared to the stiffer 10 and 20 kPa gels. Growth factor treatment did not have as obvious an effect, although the 20 kPa PDGF + FGF-treated group had significantly longer vessels than the vascular endothelial growth factor-treated group.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>We have developed a novel, tunable hydrogel assay for the creation of lung explant vessel organoids which can be modulated to study the impact of specific environmental cues on vessel formation and maturation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 5-6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12817","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9997375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Circadian and sex differences in post-ischemic vasodilation and reactive hyperemia in young individuals and elderly with and without type 2 diabetes","authors":"Alessandro Gentilin,&nbsp;Paolo Moghetti,&nbsp;Antonio Cevese,&nbsp;Anna Vittoria Mattioli,&nbsp;Federico Schena,&nbsp;Cantor Tarperi","doi":"10.1111/micc.12818","DOIUrl":"10.1111/micc.12818","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>Cardiovascular events show morning preference and sex differences, and are related to aging and type 2 diabetes. We assessed circadian variations and sex differences in vascular conductance (VC) and blood flow (BF) regulations following a brief bout of forearm ischemia.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Young healthy individuals (H18-30) and elderly without (H50-80) and with type 2 diabetes (T2DM50-80) of both sexes were included. Forearm VC and BF, and mean arterial pressure (MAP) at baseline and following circulatory reperfusion were measured at 6 a.m. and 9 p.m.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In the morning compared to evening, following reperfusion, the VC and BF increments were similar in H18-30 (p<i>&gt;</i>.71), but lower in H50-80 (p<i>&lt;</i>.001) and T2DM50-80 (p<i>&lt;</i>.01). VC and BF following circulatory reperfusion were higher in men than women in H18-30 (p<i>&lt;</i>.001), but similar between sexes in the older groups (p<i>&gt;</i>.23).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Forearm vasodilation following reperfusion is attenuated in the morning in the elderly, impairing BF towards an ischemic area. Diabetes does not affect the circadian regulation of VC and BF, but that of MAP. There are sex differences in VC and BF at baseline and after circulatory reperfusion at a young age, being greater in men, which disappear with aging without being affected by diabetes.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 5-6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9970418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"5-HT7 receptors mediate dilation of rat cremaster muscle arterioles in vivo","authors":"William F. Jackson,&nbsp;Armond Daci,&nbsp;Janice M. Thompson,&nbsp;Gregory D. Fink,&nbsp;Stephanie W. Watts","doi":"10.1111/micc.12808","DOIUrl":"https://doi.org/10.1111/micc.12808","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>Serotonin (5-HT) infusion in vivo causes hypotension and a fall in total peripheral resistance. However, the vascular segment and the receptors that mediate this response remain in question. We hypothesized that 5-HT₇ receptors mediate arteriolar dilation to 5-HT in skeletal muscle microcirculation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Cremaster muscles of isoflurane-anesthetized male Sprague-Dawley rats were prepared for in vivo microscopy of third- and fourth-order arterioles and superfused with physiological salt solution at 34°C. Quantitative real-time PCR (RT-PCR) was applied to pooled samples of first- to third-order cremaster arterioles (2–4 rats/sample) to evaluate 5-HT₇ receptor expression.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Topical 5-HT (1–10 nmols) or the 5-HT_1/7 receptor agonist, 5-carboxamidotryptamine (10–30 nM), dilated third- and fourth-order arterioles, responses that were abolished by 1 μM SB269970, a selective 5-HT₇ receptor antagonist. In contrast, dilation induced by the muscarinic agonist, methacholine (100 nmols) was not inhibited by SB269970. Serotonin (10 nmols) failed to dilate cremaster arterioles in 5-HT₇ receptor knockout rats whereas arterioles in wild-type litter mates dilated to 1 nmol 5-HT, a response blocked by 1 μM SB269970. Quantitative RT-PCR revealed that cremaster arterioles expressed mRNA for 5-HT₇ receptors.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>5-HT₇ receptors mediate dilation of small arterioles in skeletal muscle and likely contribute to 5-HT-induced hypotension, in vivo.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18459,"journal":{"name":"Microcirculation","volume":"30 5-6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/micc.12808","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50137922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}