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Nitric Oxide : Biology and Chemistry Aug 2016S-nitrosothiols (SNOs) are metabolites of NO with potent vasodilatory activity. Our previous studies in sheep indicated that intra-arterially infused SNOs dilate the...
S-nitrosothiols (SNOs) are metabolites of NO with potent vasodilatory activity. Our previous studies in sheep indicated that intra-arterially infused SNOs dilate the mesenteric vasculature more than the femoral vasculature. We hypothesized that the mesenteric artery is more responsive to SNO-mediated vasodilation, and investigated various steps along the NO/cGMP pathway to determine the mechanism for this difference. In anesthetized adult sheep, we monitored the conductance of mesenteric and femoral arteries during infusion of S-nitroso-l-cysteine (L-cysNO), and found mesenteric vascular conductance increased (137 ± 3%) significantly more than femoral conductance (26 ± 25%). Similar results were found in wire myography studies of isolated sheep mesenteric and femoral arteries. Vasodilation by SNOs was attenuated in both vessel types by the presence of ODQ (sGC inhibitor), and both YC-1 (sGC agonist) and 8-Br-cGMP (cGMP analog) mediated more potent relaxation in mesenteric arteries than femoral arteries. The vasodilatory difference between mesenteric and femoral arteries was eliminated by antagonists of either protein kinase G or L-type Ca(2+) channels. Western immunoblots showed a larger L-type Ca(2+)/sGC abundance ratio in mesenteric arteries than in femoral arteries. Fetal sheep mesenteric arteries were more responsive to SNOs than adult mesenteric arteries, and had a greater L-Ca(2+)/sGC ratio (p = 0.047 and r = -0.906 for correlation between Emax and L-Ca(2+)/sGC). These results suggest that mesenteric arteries, especially those in fetus, are more responsive to SNO-mediated vasodilation than femoral arteries due to a greater role of the L-type calcium channel in the NO/cGMP pathway.
Topics: Animals; Calcium Channel Blockers; Calcium Channels, L-Type; Cyclic GMP; Cysteine; Diltiazem; Female; Femoral Artery; Fetus; Indazoles; Male; Mesenteric Arteries; Nifedipine; Oxadiazoles; Quinoxalines; S-Nitrosoglutathione; S-Nitrosothiols; Sheep; Soluble Guanylyl Cyclase; Vasodilation; Vasodilator Agents
PubMed: 27235767
DOI: 10.1016/j.niox.2016.05.006 -
Annals of the Royal College of Surgeons... Nov 2016INTRODUCTION Hemicolectomies are not tailored in right-sided colon cancer resections, despite significant variation in the incidence and origin of the right colic artery...
INTRODUCTION Hemicolectomies are not tailored in right-sided colon cancer resections, despite significant variation in the incidence and origin of the right colic artery (RCA). Early evidence suggests that removal of the relevant lymphovascular package and associated cancer as part of complete mesocolic excision (CME), rather than the entire right colon, may produce better outcomes. Advancing laparoscopic techniques are making this possible, and so it is increasingly important to more precisely define the anatomy of the RCA. METHODS To demonstrate the incidence and variation of the RCA, 25 formalin embalmed cadavers were dissected. Consent to dissection and photography was obtained under Human Tissue Act regulations. RESULTS Eleven female and 14 male cadavers (mean age 79.7 years, range 41-95 years) were included. The RCA originated from the right branch of the middle colic artery in nine cadavers (36%), while it arose from the superior mesenteric artery in eight cases (32%) and from the ileocolic or root of the middle colic artery in a smaller number of specimens. The RCA was absent in two individuals. CONCLUSIONS The RCA arises from the right branch of the middle colic artery in a considerable number of cases. The literature to date does not reflect the precision of anatomical understanding required for CME; hence, a new definition for the right colic vessel is proposed.
Topics: Adult; Aged; Aged, 80 and over; Colon; Female; Humans; Laparoscopy; Male; Mesenteric Arteries; Middle Aged
PubMed: 27502338
DOI: 10.1308/rcsann.2016.0257 -
Vascular Health and Risk Management 2020Laparoscopic aortomesenteric bypass may be performed to treat the chronic mesenteric ischemia patients who are not suitable for endovascular treatment. This study...
BACKGROUND
Laparoscopic aortomesenteric bypass may be performed to treat the chronic mesenteric ischemia patients who are not suitable for endovascular treatment. This study presents an initial experience with a limited series of laparoscopic mesenteric artery revascularization for the treatment of mesenteric ischemia.
METHODS
Chronic mesenteric ischemia (CMI) patients with previous unsuccessful endovascular treatment or with arterial occlusion and extensive calcification precluding safe endovascular treatment were offered laparoscopic mesenteric revascularization. From October 2015 until November 2018, nine patients with CMI underwent laparoscopic revascularization. In addition to demographic data and perioperative results of the treatment, graft patency was assessed with Duplex ultrasound at 1, 3, 6 and 12 months, and annually thereafter. A descriptive analysis of the data was performed.
RESULTS
All bypasses were constructed with an 8 mm ring enforced expanded polytetrafluoroethylene graft in a retrograde fashion (from infrarenal aorta or iliac artery) to either superior mesenteric artery or splenic artery (2 cases). Median operation time was 356 mins (range 247-492 mins). Five patients had a history of unsuccessful endovascular treatment. Laparoscopic technical success was 78%, and the primary open conversion rate was 22%. All laparoscopic revascularization procedures remained patent after discharge during a median follow-up time of 26 months (range 18-49 months). The primary graft patency at 30 days was 78%. Primary assisted, and secondary graft patency was 78% and 100%, respectively. Median weight gain was 2 kg (range 2-18 kg), and all patients achieved relief from postprandial pain and nausea. No mortality was observed during the follow-up period.
CONCLUSION
Laparoscopic aortomesenteric revascularization procedures for chronic mesenteric ischemia are feasible but require careful patient selection. These procedures should only be performed at referral centers by vascular surgeons with prior experience in laparoscopic vascular surgery.
Topics: Aged; Blood Vessel Prosthesis Implantation; Chronic Disease; Female; Graft Occlusion, Vascular; Humans; Laparoscopy; Male; Mesenteric Arteries; Mesenteric Ischemia; Mesenteric Vascular Occlusion; Middle Aged; Prospective Studies; Reoperation; Splanchnic Circulation; Time Factors; Treatment Outcome; Vascular Patency
PubMed: 32256075
DOI: 10.2147/VHRM.S243264 -
PloS One 2021Respiratory-gated four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) is magnetic resonance (MR) imaging technique that... (Comparative Study)
Comparative Study
Daikenchuto increases blood flow in the superior mesenteric artery in humans: A comparison study between four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction magnetic resonance imaging and Doppler ultrasound.
Respiratory-gated four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) is magnetic resonance (MR) imaging technique that enables analysis of vascular morphology and hemodynamics in a single examination using cardiac phase resolved 3D phase-contrast magnetic resonance imaging. The present study aimed to assess the usefulness of 4D PC-VIPR for the superior mesenteric artery (SMA) flowmetry before and after flow increase was induced by the herbal medicine Daikenchuto (TJ-100) by comparing it with Doppler ultrasound (DUS) as a current standard. Twenty healthy volunteers were enrolled in this prospective single-arm study. The peak cross-sectionally averaged velocity was measured by 4D PC-VIPR, peak velocity was measured by DUS, and flow volume (FV) of SMA and aorta were measured by 4D PC-VIPR and DUS 25 min before and after the peroral administration of TJ-100. The peak cross-sectionally averaged velocity, peak velocity, and FV of SMA measured by 4D PC-VIPR and DUS significantly increased after administration of TJ-100 (4D PC-VIPR: the peak cross-sectionally averaged velocity; p = 0.004, FV; p = 0.035, DUS: the peak velocity; p = 0.003, FV; p = 0.010). Furthermore, 4D PC-VIPR can analyze multiple blood vessels simultaneously. The ratio of the SMA FV to the aorta, before and after oral administration on the 4D PC-VIPR test also increased (p = 0.015). The rate of change assessed by 4D PC-VIPR and DUS were significantly correlated (the peak cross-sectionally averaged velocity and peak velocity: r = 0.650; p = 0.005, FV: r = 0.659; p = 0.004). Retrospective 4D PC-VIPR was a useful modality for morphological and hemodynamic analysis of SMA.
Topics: Adult; Blood Flow Velocity; Female; Humans; Magnetic Resonance Imaging; Male; Mesenteric Arteries; Panax; Plant Extracts; Respiratory-Gated Imaging Techniques; Ultrasonography, Doppler; Zanthoxylum; Zingiberaceae
PubMed: 33503053
DOI: 10.1371/journal.pone.0245878 -
Journal of Cancer Research and... 2020To study the arterial distribution of embosphere microsphere (EM) and polyvinyl alcohol (PVA) particles in rabbit mesenteric artery using in vivo microscopy.To study the...
PURPOSE
To study the arterial distribution of embosphere microsphere (EM) and polyvinyl alcohol (PVA) particles in rabbit mesenteric artery using in vivo microscopy.To study the arterial distribution of embosphere microsphere (EM) and polyvinyl alcohol (PVA) particles in rabbit mesenteric artery using in vivo microscopy.
METHODS
Sixteen New Zealand rabbits were divided into four groups, namely large PVA (560-710 μm), small PVA (150-350 μm), large EM (500-700 μm), and small EM (100-300 μm). The mesenteric arteries of the experimental animals were embolized under fluoroscopic guidance and visualized using in vivo microscopy. The embolized vessel diameter and arterial distribution of embolic agents were compared.
RESULTS
The diameters of occluded vessels in large PVA, small PVA, large EM, and small EM groups were 430.60 ± 67.30, 200.95 ± 70.54, 387.79 ± 92.51, and 143.81 ± 39.65 μm, respectively. PVA occluded significantly larger vessels than EM when the particle size was similar (P < 0.001). The proportion of EM at the bifurcation of the artery was significantly higher than that of PVA particles (large PVA < large EM, χ = 4.325, P < 0.038; small PVA < small EM, χ = 6.68, P < 0.01).
CONCLUSION
Both PVA and EM could occlude vessels smaller than the particle size, and EM resulted in deeper penetration. The location of embolic particles in the artery is mainly related to the shape of particles.
Topics: Angiography; Animals; Drug Delivery Systems; Embolization, Therapeutic; Intravital Microscopy; Mesenteric Arteries; Microspheres; Models, Animal; Particle Size; Polyvinyl Alcohol; Rabbits
PubMed: 32474513
DOI: 10.4103/jcrt.JCRT_435_19 -
Shock (Augusta, Ga.) Jul 2016Intestinal ischemia can quickly escalate to bowel necrosis and perforation. Transplantation of stem cells presents a novel treatment modality for this problem. We...
OBJECTIVE
Intestinal ischemia can quickly escalate to bowel necrosis and perforation. Transplantation of stem cells presents a novel treatment modality for this problem. We hypothesized that: human adipose-derived stromal cells (hASCs) would increase survival and mesenteric perfusion to a greater degree compared with differentiated cellular controls following ischemic intestinal injury, and improved outcomes with hASC therapy would be associated with preservation of intestinal histological and tight junction architecture, and lower levels of systemic inflammation following intestinal injury.
METHODS
hASCs and keratinocytes (differentiated cellular control) were cultured on polystyrene flasks at 37°C in 5% CO2 in air. Adult male C57Bl6J mice were anesthetized and a midline laparotomy performed. The intestines were eviscerated, the small bowel mesenteric root identified, and intestinal ischemia was established by temporarily occluding the superior mesenteric artery for 60 min with a noncrushing vascular clamp. Following ischemia, the clamp was removed, and the intestines were returned to the abdominal cavity. Before abdominal closure, 2 million hASCs or keratinocytes in 250 μL of phosphate-buffered saline (carrier for cells and control solution) were infused into the peritoneum. Animals were allowed to recover for 12 or 24 h (perfusion, histology, cytokine, and immunofluoresence studies), or 7 days (survival studies). Intestinal perfusion was assessed by laser Doppler imaging. Intestinal tissue segments were stained with hematoxylin and eosin, as well as antibodies for the tight junction protein claudin-1. Separate aliquots of intestine, liver, and lung tissue were homogenized and assessed for inflammatory cytokines via multiplex beaded assay.
RESULTS
Animals administered hASCs following intestinal ischemia and reperfusion (I/R) injury had significantly greater 7-day survival and better postischemic recovery of mesenteric perfusion compared with vehicle or keratinocyte therapy. hASCs also abated intestinal mucosal destruction, facilitated preservation of intestinal tight junctions, and decreased the systemic inflammatory response to injury.
CONCLUSIONS
Human adipose-derived stromal cells improved survival and mesenteric perfusion and attenuated the mucosal damage associated with intestinal I/R injury. hASCs should be considered as a plausible cell source for novel cellular treatment plans following intestinal ischemia.
Topics: Adipose Tissue; Animals; Humans; Inflammation; Intestinal Diseases; Liver; Lung; Male; Mesenteric Arteries; Mice, Inbred C57BL; Reperfusion Injury; Stromal Cells
PubMed: 26796571
DOI: 10.1097/SHK.0000000000000571 -
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 -
Arteriosclerosis, Thrombosis, and... Sep 2018Objective- In renal arteries, inhibitors of G protein βγ subunits (Gβγ) reduce Kv7 activity and inhibit Kv7-dependent receptor-mediated vasorelaxations. However, the...
Objective- In renal arteries, inhibitors of G protein βγ subunits (Gβγ) reduce Kv7 activity and inhibit Kv7-dependent receptor-mediated vasorelaxations. However, the mechanisms underlying receptor-mediated relaxation are artery specific. Consequently, the aim of this study was to ascertain the role of Gβγ in Kv7-dependent vasorelaxations of the rat vasculature. Approach and Results- Isometric tension recording was performed in isolated rat renal, mesenteric, and cerebral arteries to study isoproterenol and calcitonin gene-related peptide relaxations. Kv7.4 was knocked down via morpholino transfection while inhibition of Gβγ was investigated with gallein and M119K. Proximity ligation assay was performed on isolated myocytes to study the association between Kv7.4 and G protein β subunits or signaling intermediaries. Isoproterenol or calcitonin gene-related peptide-induced relaxations were attenuated by Kv7.4 knockdown in all arteries studied. Inhibition of Gβγ with gallein or M119K had no effect on isoproterenol-mediated relaxations in mesenteric artery but had a marked effect on calcitonin gene-related peptide-induced responses in mesenteric artery and cerebral artery and isoproterenol responses in renal artery. Isoproterenol increased association with Kv7.4 and Rap1a in mesenteric artery which were not sensitive to gallein, whereas in renal artery, isoproterenol increased Kv7.4-AKAP (A-kinase anchoring protein) associations in a gallein-sensitive manner. Conclusions- The Gβγ-Kv7 relationship differs between vessels and is an essential requirement for AKAP, but not Rap-mediated regulation of the channel.
Topics: A Kinase Anchor Proteins; Animals; Calcitonin Gene-Related Peptide; Cerebral Arteries; GTP-Binding Protein beta Subunits; GTP-Binding Protein gamma Subunits; Isoproterenol; KCNQ Potassium Channels; Male; Mesenteric Arteries; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Rats, Wistar; Renal Artery; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents; Xanthenes
PubMed: 30002060
DOI: 10.1161/ATVBAHA.118.311360 -
European Journal of Vascular and... Dec 2019The aim was to investigate the effectiveness of colour duplex ultrasound (CDU) plus contrast enhanced ultrasound (CEUS) vs. computed tomography angiography (CTA) for... (Comparative Study)
Comparative Study
OBJECTIVES
The aim was to investigate the effectiveness of colour duplex ultrasound (CDU) plus contrast enhanced ultrasound (CEUS) vs. computed tomography angiography (CTA) for surveillance in patients with isolated mesenteric artery dissection (IMAD).
METHODS
Patients who underwent CDU, CEUS, and CTA for surveillance of IMAD between January 2012 and May 2019 were included in the study. The accuracy of CDU, CEUS, and CTA for determining the morphological characteristics of IMAD was analysed.
RESULTS
A total of 42 patients undergoing 76 total imaging examinations during follow up were included. Both CTA and CDU plus CEUS demonstrated the thrombosed false lumen for 28 (36.8%) examinations and the dissecting aneurysm for 20 (26.3%) examinations (both κ = 1.0). The diameter of the dissecting aneurysm was 5.03 ± 1.25 mm using CDU and CEUS vs. 5.27 ± 1.23 mm on CTA (coefficient of consistency, 0.997; p < .001). The entry points were visualised by CDU and CEUS for 20 (26.3%) examinations and by CTA for 14 (18.4%) examinations (κ = 0.769); no re-entry points were visualised by CDU and CEUS for any examinations but re-entry points were visualised by CTA for two (2.6%) examinations. The minimum inner diameter was 2.80 ± 1.30 mm on CDU and CEUS vs. 2.52 ± 1.29 mm on CTA (coefficient of consistency, 0.999; p < .001). The peak systolic velocities were 128.2 ± 13.0 cm/s at diagnosis and 98.7 ± 4.9 cm/s after one month (p < .001).
CONCLUSIONS
The combination of CDU and CEUS can be used in place of CTA for the surveillance of IMAD.
Topics: Adult; Aged; Aortic Dissection; Computed Tomography Angiography; Conservative Treatment; Contrast Media; Endovascular Procedures; Feasibility Studies; Female; Follow-Up Studies; Humans; Male; Mesenteric Arteries; Middle Aged; Multimodal Imaging; Stents; Ultrasonography, Doppler, Duplex
PubMed: 31607680
DOI: 10.1016/j.ejvs.2019.07.019 -
British Journal of Pharmacology May 2016Berberine, a small molecule derived from Coptidis rhizome, has been found to be potent at lowering blood glucose and regulating lipid metabolism. Recent clinical studies...
BACKGROUND AND PURPOSE
Berberine, a small molecule derived from Coptidis rhizome, has been found to be potent at lowering blood glucose and regulating lipid metabolism. Recent clinical studies have shown that berberine reduces blood pressure and increases systemic insulin sensitivity in patients with metabolic syndrome; however, the underlying mechanism is still unclear. Here, we investigated the mechanism by which berberine improves vascular insulin sensitivity in diabetic rats.
EXPERIMENTAL APPROACH
Diabetes was induced in male Sprague–Dawley rats by feeding a high-fat diet and administration of a low dose of streptozotocin. These diabetic rats were treated with berberine (200 mg·kg(−1)·day(−1), gavage) for 4 weeks. Vascular dilation was determined in isolated mesenteric artery rings. Effects of berberine on insulin signalling were also studied in human artery endothelial cells cultured in high glucose (25 mmol·L(−1)) and palmitate (500 μmol·L(−1)).
KEY RESULTS
Berberine treatment for 4 weeks significantly restored the impaired ACh- and insulin-induced vasodilatation of mesenteric arteries from diabetic rats. In isolated mesenteric artery rings, berberine (2.5–10 μmol·L(−1)) elicited dose-dependent vasodilatation and significantly enhanced insulin-induced vasodilatation. Mechanistically, berberine up-regulated phosphorylation of the insulin receptor and its downstream signalling molecules AMPK, Akt and eNOS, and increased cell viability and autophagy in cultured endothelial cells. Moreover, down-regulating insulin receptors with specific siRNA significantly attenuated berberine-induced phosphorylation of AMPK.
CONCLUSIONS AND IMPLICATIONS
Berberine improves diabetic vascular insulin sensitivity and mesenteric vasodilatation by up-regulating insulin receptor-mediated signalling in diabetic rats. These findings suggest berberine has potential as a preventive or adjunctive treatment of diabetic vascular complications.
LINKED ARTICLES
This article is part of a themed section on Chinese Innovation in Cardiovascular Drug Discovery. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-23.
Topics: Acetylcholine; Animals; Berberine; Blood Glucose; Cell Line; Endothelium, Vascular; Humans; Insulin; Insulin Resistance; Male; Mesenteric Arteries; RNA, Small Interfering; Rats; Rats, Sprague-Dawley; Receptor, Insulin; Signal Transduction; Up-Regulation; Vasodilation
PubMed: 26914282
DOI: 10.1111/bph.13466