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Journal of Vascular Surgery Jan 2018
Topics: Abdominal Pain; Axillary Artery; Computed Tomography Angiography; Humans; Ischemia; Male; Mesenteric Arteries; Mesenteric Vascular Occlusion; Middle Aged; Postprandial Period; Vascular Grafting
PubMed: 29268920
DOI: 10.1016/j.jvs.2016.08.088 -
International Journal of Molecular... Nov 2021(1) Background: Chronic increases in blood flow, as in cardiovascular diseases, induce outward arterial remodeling. Thrombospondin-1 (TSP-1) is known to interact with...
(1) Background: Chronic increases in blood flow, as in cardiovascular diseases, induce outward arterial remodeling. Thrombospondin-1 (TSP-1) is known to interact with matrix proteins and immune cell-surface receptors, but its contribution to flow-mediated remodeling in the microcirculation remains unknown. (2) Methods: Mesenteric arteries were ligated in vivo to generate high- (HF) and normal-flow (NF) arteries in wild-type (WT) and TSP-1-deleted mice (TSP-1). After 7 days, arteries were isolated and studied ex vivo. (3) Results: Chronic increases in blood flow induced outward remodeling in WT mice (increasing diameter from 221 ± 10 to 280 ± 10 µm with 75 mmHg intraluminal pressure) without significant effect in TSP-1 (296 ± 18 to 303 ± 14 µm), neutropenic or adoptive bone marrow transfer mice. Four days after ligature, pro inflammatory gene expression levels (CD68, Cox2, Gp91phox, p47phox and p22phox) increased in WT HF arteries but not in TSP-1 mice. Perivascular neutrophil accumulation at day 4 was significantly lower in TSP-1 than in WT mice. (4) Conclusions: TSP-1 origin is important; indeed, circulating TSP-1 participates in vasodilation, whereas both circulating and tissue TSP-1 are involved in arterial wall thickness and diameter expansion.
Topics: Animals; Endothelium, Vascular; Mesenteric Arteries; Mice; Mice, Knockout; Microcirculation; Models, Animal; Regional Blood Flow; Thrombospondin 1; Vasodilation
PubMed: 34769516
DOI: 10.3390/ijms222112086 -
Cellular and Molecular Neurobiology Oct 2021Melatonin is released by the pineal gland and can modulate cardiovascular system function via the G protein-coupled melatonin receptors MT and MT. Most vessels are...
Melatonin is released by the pineal gland and can modulate cardiovascular system function via the G protein-coupled melatonin receptors MT and MT. Most vessels are surrounded by perivascular adipose tissue (PVAT), which affects their contractility. The aim of our study was to evaluate mRNA and protein expression of MT and MT in the mesenteric artery (MA) and associated PVAT of male rats by RT-PCR and Western blot. Receptor localization was further studied by immunofluorescence microscopy. Effects of melatonin on neurogenic contractions were explored in isolated superior MA ex vivo by measurement of isometric contractile tension. MT, but not MT, was present in MA, and MT was localized mainly in vascular smooth muscle. Moreover, we proved the presence of MT, but not MT receptors, in MA-associated PVAT. In isolated superior MA with intact PVAT, neuro-adrenergic contractile responses were significantly smaller when compared to arteries with removed PVAT. Pre-treatment with melatonin of PVAT-stripped arterial rings enhanced neurogenic contractions, while the potentiating effect of melatonin was not detected in preparations with preserved PVAT. We hypothesize that melatonin can stimulate the release of PVAT-derived relaxing factor(s) via MT, which can override the direct pro-contractile effect of melatonin on vascular smooth muscle. Our results suggest that melatonin is involved in the control of vascular tone in a complex way, which is vessel specific and can reflect a sum of action on different layers of the vessel wall and surrounding PVAT.
Topics: Adipose Tissue; Animals; Melatonin; Mesenteric Arteries; Muscle, Smooth, Vascular; Norepinephrine; Rats, Wistar; Receptors, Melatonin; Rats
PubMed: 32734322
DOI: 10.1007/s10571-020-00928-w -
Techniques in Coloproctology Mar 2017Exercise in the preoperative period, or prehabilitation, continues to evolve as an important tool in optimising patients awaiting major intra-abdominal surgery. It has... (Review)
Review
BACKGROUND
Exercise in the preoperative period, or prehabilitation, continues to evolve as an important tool in optimising patients awaiting major intra-abdominal surgery. It has been shown to reduce rates of post-operative morbidity and length of hospital stay. The mechanism by which this is achieved remains poorly understood. Adaptations in mesenteric flow in response to exercise may play a role in improving post-operative recovery by reducing rates of ileus and anastomotic leak.
AIMS
To systematically review the existing literature to clarify the impact of exercise on mesenteric arterial blood flow using Doppler ultrasound.
METHODS
PubMed, EMBASE and the Cochrane library were systematically searched to identify clinical trials using Doppler ultrasound to investigate the effect of exercise on flow through the superior mesenteric artery (SMA). Data were extracted including participant characteristics, frequency, intensity, timing and type of exercise and the effect on SMA flow. The quality of each study was assessed using the Downs and Black checklist.
RESULTS
Sixteen studies, comprising 305 participants in total, were included. Methodological quality was generally poor. Healthy volunteers were used in twelve studies. SMA flow was found to be reduced in response to exercise in twelve studies, increased in one and unchanged in two studies. Clinical heterogeneity precluded a meta-analysis.
CONCLUSION
The weight of evidence suggests that superior mesenteric arterial flow is reduced immediately following exercise. Differences in frequency, intensity, timing and type of exercise make a consensus difficult. Further studies are warranted to provide a definitive understanding of the impact of exercise on mesenteric flow.
Topics: Abdomen; Adult; Aged; Anastomotic Leak; Clinical Trials as Topic; Digestive System Surgical Procedures; Echocardiography, Doppler; Exercise; Exercise Therapy; Female; Humans; Ileus; Male; Mesenteric Arteries; Middle Aged; Preoperative Period; Splanchnic Circulation; Treatment Outcome; Young Adult
PubMed: 28243813
DOI: 10.1007/s10151-017-1589-9 -
Journal of Biomechanics Apr 2021Elastic and muscular arteries are distinguished by their distinct microstructures, biomechanical properties, and smooth muscle cell contractile functions. They also...
Elastic and muscular arteries are distinguished by their distinct microstructures, biomechanical properties, and smooth muscle cell contractile functions. They also exhibit differential remodeling in aging and hypertension. Although regional differences in biomechanical properties have been compared, few studies have quantified biaxial differences in response to hypertension. Here, we contrast passive and active changes in large elastic and medium- and small-sized muscular arteries in adult mice in response to chronic infusion of angiotensin over 14 days. We found a significant increase in wall thickness, both medial and adventitial, in the descending thoracic aorta that associated with trends of an increased collagen:elastin ratio. There was adventitial thickening in the small-sized mesenteric artery, but also significant changes in elastic lamellar structure and contractility. An increased contractile response to phenylephrine coupled with a reduced vasodilatory response to acetylcholine in the mesenteric artery suggested an increased contractile state in response to hypertension. Overall reductions in the calculated gradients in pulse wave velocity and elastin energy storage capability from elastic-to-muscular arteries suggested a possible transfer of excessive pulsatile energy into the small-sized muscular arteries resulting in significant functional consequences in response to hypertension.
Topics: Angiotensin II; Animals; Arteries; Elastin; Hypertension; Mesenteric Arteries; Mice; Pulse Wave Analysis
PubMed: 33647550
DOI: 10.1016/j.jbiomech.2021.110297 -
Journal of Vascular Surgery Jul 2017Isolated dissection of the mesenteric vessels is rare but increasingly recognized. This study aimed to evaluate patient characteristics, primary treatment, and... (Comparative Study)
Comparative Study
OBJECTIVE
Isolated dissection of the mesenteric vessels is rare but increasingly recognized. This study aimed to evaluate patient characteristics, primary treatment, and subsequent outcomes of mesenteric dissection using multi-institutional data.
METHODS
All patients at participant hospitals between January 2003 and December 2015 with dissection of the celiac artery (or its branches) or dissection of the superior mesenteric artery (SMA) were included. Patients with an aortic dissection were excluded. Demographic, treatment, and follow-up data were collected. The primary outcomes included late vessel thrombosis (LVT) and aneurysmal degeneration (AD).
RESULTS
Twelve institutions identified 227 patients (220 with complete treatment records) with a mean age of 55 ± 12.5 years. Median time to last follow up was 15 months (interquartile range, 3.8-32). Most patients were men (82% vs 18% women) and symptomatic at presentation (162 vs 65 asymptomatic). Isolated SMA dissection was more common than celiac artery dissection (n = 158 and 81, respectively). Concomitant dissection of both arteries was rare (n = 12). The mean dissection length was significantly longer in symptomatic patients than in asymptomatic patients in both the celiac artery (27 vs 18 mm; P = .01) and the SMA (64 vs 40 mm; P < .001). Primary treatment was medical in 146 patients with oral anticoagulation or antiplatelet therapy (n = 76 and 70, respectively), whereas 56 patients were observed. LVT occurred in six patients, and 16 patients developed AD (3% and 8%, respectively). For symptomatic patients without evidence of ischemia (n = 134), there was no difference in occurrence of LVT with medical therapy compared with observation alone (9% vs 0%; P = .35). No asymptomatic patient (n = 64) had an episode of LVT at 5 years. AD rates did not differ among symptomatic patients without ischemia treated with medical therapy or observed (9% vs 5%; P = .95). Surgical or endovascular intervention was performed in 18 patients (3 ischemia, 13 pain, 1 AD, 1 asymptomatic). Excluding the patients treated for ischemia, there was no difference in LVT with surgical intervention vs medical management (one vs five; P = .57).
CONCLUSIONS
Asymptomatic patients with isolated mesenteric artery dissection may be observed and followed up with intermittent imaging. Symptomatic patients tend to have longer dissections than asymptomatic patients. Symptomatic isolated mesenteric artery dissection without evidence of ischemia does not require anticoagulation and may be treated with antiplatelet therapy or observation alone.
Topics: Administration, Oral; Adult; Aged; Aortic Dissection; Anticoagulants; Asymptomatic Diseases; Celiac Artery; Disease Progression; Endovascular Procedures; Europe; Female; Humans; Japan; Male; Mesenteric Artery, Superior; Middle Aged; Platelet Aggregation Inhibitors; Retrospective Studies; Risk Factors; Thrombosis; Time Factors; Treatment Outcome; United States; Vascular Surgical Procedures; Watchful Waiting
PubMed: 28506477
DOI: 10.1016/j.jvs.2017.01.059 -
Experimental Physiology May 2019What is the central question of this study? Visceral ischaemia is one of the most feared complications during use of an intra-aortic balloon pump. Using an animal model,...
NEW FINDINGS
What is the central question of this study? Visceral ischaemia is one of the most feared complications during use of an intra-aortic balloon pump. Using an animal model, we measured the flows at the abdominal level directly and examined flow patterns to enable investigation of flow patterns during the use of the intra-aortic balloon pump. What is the main finding and its importance? We show that there is a significant balloon-related reduction in superior mesenteric flow in both early and mid-diastole.
ABSTRACT
A number of previous studies have shown that blood flow in the visceral arteries is altered during intra-aortic balloon pump (IABP) treatment. We used a porcine model to analyse the pattern of blood flow into the visceral arteries during IABP use. For this purpose, we measured the superior mesenteric, right renal and left renal flows before and during IABP support, using surgically placed flowmeters surrounding these visceral arteries. The superior mesenteric flow significantly decreased in early diastole (P < 0.001) and in mid-diastole (P = 0.003 versus early diastole), whereas in late diastole it increased again (P < 0.001 versus mid-diastole). During systole, the flow was not significantly increased compared with late diastole (P = 0.51), but it was significantly lower than at baseline (both P < 0.001). Flows did not differ between right and left kidneys. Perfusion of either kidney did not change significantly in early diastole (P > 0.05), whereas it decreased significantly in mid-diastole (P < 0.001), rising dramatically in late diastole (P < 0.001) and with an additional slight increase in systole (P = 0.054). This study provides important insights into abdominal flows during intra-aortic pump counterpulsation. Furthermore, it supports the need to rethink the balloon design to avoid visceral ischaemia during circulatory assistance.
Topics: Animals; Blood Flow Velocity; Counterpulsation; Diastole; Electrocardiography; Hemodynamics; Intra-Aortic Balloon Pumping; Mesenteric Artery, Superior; Monitoring, Physiologic; Renal Circulation; Rheology; Swine; Systole
PubMed: 30821049
DOI: 10.1113/EP086810 -
European Journal of Vascular and... Jul 2023
Topics: Humans; Mesenteric Artery, Inferior; Colitis, Ischemic; Embolism; Mesenteric Vascular Occlusion; Mesenteric Artery, Superior; Mesenteric Arteries
PubMed: 37087071
DOI: 10.1016/j.ejvs.2023.04.018 -
Surgical and Radiologic Anatomy : SRA Dec 2018Controversy exists as to whether a high or low tie ligation of the inferior mesenteric artery (IMA) is the preferred technique in surgeries of the left colon and rectum....
PURPOSE
Controversy exists as to whether a high or low tie ligation of the inferior mesenteric artery (IMA) is the preferred technique in surgeries of the left colon and rectum. This study aims to contribute to the discussion as to which is the more beneficial technique by investigating the neurovasculature at each site.
METHODS
Ten embalmed cadaveric donors underwent division of the inferior mesenteric artery at the level of the low tie. The artery was subsequently ligated at the root to render a section of tissue for histological analysis of the proximal (high tie), mid and distal (low tie) segments.
RESULTS
Ganglia observed in the proximal end of seven specimens in the sample imply that there would be disruption to the innervation in a high tie procedure.
CONCLUSION
This study suggests that a high tie should be avoided if the low tie is oncologically viable.
Topics: Aged, 80 and over; Anastomosis, Surgical; Cadaver; Colectomy; Female; Humans; Ligation; Male; Mesenteric Artery, Inferior
PubMed: 30173375
DOI: 10.1007/s00276-018-2092-3 -
Physiological Reports Dec 2021The vasoconstrictive effect of sympathetic activity is attenuated in contracting skeletal muscle (functional sympatholysis), allowing increased blood supply to the...
The vasoconstrictive effect of sympathetic activity is attenuated in contracting skeletal muscle (functional sympatholysis), allowing increased blood supply to the working muscle but the underlying mechanisms are incompletely understood. The purpose of this study was to examine α-adrenergic receptor responsiveness in isolated artery segments from non-exercised and exercised mice, using wire myography. Isometric tension recordings performed on femoral artery segments from exercised mice showed decreased α-adrenergic receptor responsiveness compared to non-exercised mice (logEC -5.2 ± 0.04 M vs. -5.7 ± 0.08 M, respectively). In contrast, mesenteric artery segments from exercised mice displayed similar α-adrenergic receptor responses compared to non-exercised mice. Responses to the vasoconstrictor serotonin (5-HT) and vasodilator isoprenaline, were similar in femoral artery segments from non-exercised and exercised mice. To study sarcoplasmic reticulum (SR) function, we examined arterial contractions induced by caffeine, which depletes SR Ca and thapsigargin, which inhibits SR Ca -ATPase (SERCA) and SR Ca uptake. Arterial contractions to both caffeine and thapsigargin were increased in femoral artery segment from exercised compared to non-exercised mice. Furthermore, 3D electron microscopy imaging of the arterial wall showed SR volume/length ratio increased 157% in smooth muscle cells of the femoral artery from the exercised mice, whereas there was no difference in SR volume/length ratio in mesenteric artery segments. These results show that in arteries surrounding exercising muscle, the α-adrenergic receptor constrictions are blunted, which can be attributed to swollen smooth muscle cell SR's, likely due to increased Ca content that is possibly reducing free intracellular Ca available for contraction. Overall, this study uncovers a previously unknown mechanism underlying functional sympatholysis.
Topics: Animals; Caffeine; Calcium; Mesenteric Arteries; Mice; Muscle Contraction; Muscle, Skeletal; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Myography; Physical Conditioning, Animal; Sarcoplasmic Reticulum; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Sympatholytics; Vasoconstrictor Agents
PubMed: 34851043
DOI: 10.14814/phy2.15133