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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 -
American Journal of Physiology. Heart... Feb 2021Heart failure (HF) is associated with neurohumoral activation, which in turn leads to an increased peripheral resistance. In mesenteric vasculature, perivascular...
Heart failure (HF) is associated with neurohumoral activation, which in turn leads to an increased peripheral resistance. In mesenteric vasculature, perivascular innervation plays relevant role maintaining vascular tonus and resistance. Therefore, we aimed to determine the possible alterations in superior mesenteric artery (SMA) perivascular innervation function in HF rats. HF was induced by coronary artery occlusion in male Wistar rats, and sham-operated (SO) rats were used as controls. After 12 wk, a greater vasoconstrictor response to electrical field stimulation (EFS) was observed in endothelium-intact and endothelium-denuded SMA of HF rats. Alpha-adrenoceptor antagonist phentolamine diminished this response in a higher magnitude in HF than in SO animals. However, the noradrenaline (NA) reuptake inhibitor desipramine increased EFS-induced vasoconstriction more in segments from HF rats. Besides, EFS-induced NA release was greater in HF animals, due to a higher tyrosine hydroxylase expression and activity. P2 purinoceptor antagonist suramin reduced EFS-induced vasoconstriction only in segments from SO rats, and adenosine 5'-triphosphate (ATP) release was lower in HF than in SO. Moreover, nitric oxide (NO) synthase inhibitor -nitro-L-arginine methyl ester (L-NAME) enhanced EFS-induced vasoconstriction in a similar extent in both groups. HF was not associated with changes in EFS-induced NO release or the vasodilator response to NO donor sodium nitroprusside. In conclusion, HF postmyocardial infarction enhanced noradrenergic function and diminished purinergic cotransmission in SMA and did not change nitrergic innervation. The net effect was an increased sympathetic participation on the EFS-induced vasoconstriction that could help to understand the neurotransduction involved on the control of vascular tonus in HF. This study reinforces the pivotal role of noradrenergic innervation in the regulation of mesenteric vascular tone in a rat model of heart failure. Moreover, our results highlight the counteracting role of ATP and NA reuptake, and help to understand the signaling pathways involved on the control of vascular tonus and resistance in heart failure postmyocardial infarction.
Topics: Adenosine Triphosphate; Adrenergic Uptake Inhibitors; Adrenergic alpha-Antagonists; Animals; Desipramine; Enzyme Inhibitors; Heart Failure; Male; Mesenteric Arteries; NG-Nitroarginine Methyl Ester; Nitric Oxide Donors; Nitroprusside; Norepinephrine; Phentolamine; Purinergic P2 Receptor Antagonists; Rats; Rats, Wistar; Suramin; Sympathetic Nervous System; Synaptic Transmission; Vasoconstriction
PubMed: 33164582
DOI: 10.1152/ajpheart.00444.2020 -
Annals of Anatomy = Anatomischer... Apr 2023The cranial mesenteric artery exhibits a species-specific ramification pattern that adapts to the morphology of the intestinal tract. The degu is a strictly herbivorous...
BACKGROUND
The cranial mesenteric artery exhibits a species-specific ramification pattern that adapts to the morphology of the intestinal tract. The degu is a strictly herbivorous rodent with a well-developed large intestine with a spiral loop in the ascending colon; therefore, the cranial mesenteric artery likely demonstrates a degu-specific ramification pattern. Thus, we traced the cranial mesenteric artery to establish the detailed ramification pattern of the branches.
METHODS
Eighteen male degus were injected with 0.3-0.8 ml of a latex mixture and water at a 1:1 ratio in conjunction with red acrylic paint coloring using a catheter inserted into the thoracic aorta. The cranial mesenteric artery was traced using a surgical microscope and photographed using a digital camera.
RESULTS
The arteries emerging from the cranial mesenteric artery exhibited frequent variations in number, distribution area, anastomosis pattern, and branching order. In the most frequent cases (22%), the cranial mesenteric artery sequentially gave rise to caudal pancreaticoduodenal, middle colic, right colic, jejunal, and ileocolic arteries. The right and middle colic arteries exhibited four different ramification patterns. In the most common cases (67%), the middle and right colic arteries emerged independently from the cranial mesenteric artery. The former was distributed to the transverse and descending colon, whereas the latter sent branches to the spiral loop of the ascending colon.
CONCLUSIONS
The complex ramification pattern of the right colic artery in the degu may be an adaptation to the characteristic running pattern of the ascending colon. Thus, we present the first comprehensive report of the arterial branching pattern of the cranial mesenteric artery in the degu.
Topics: Animals; Male; Octodon; Colic; Mesenteric Arteries; Mesenteric Artery, Superior; Intestines; Colon
PubMed: 36754241
DOI: 10.1016/j.aanat.2023.152067 -
Surgical and Radiologic Anatomy : SRA Mar 2019There is confusion regarding the names, the number, and the exact location of the colonic arterial arches which provide connections between the superior and inferior...
PURPOSE
There is confusion regarding the names, the number, and the exact location of the colonic arterial arches which provide connections between the superior and inferior (IMA) mesenteric arteries at the level of the left colic angle. The aim of this review was to delineate the "true" colic arches arising in the meso of the left colic angle and to describe their surgical implications.
METHODS
A systematic review of the literature was performed using the MEDLINE database. The search included only human studies between 1913 and 2018. All dissection, angiographic, arterial cast and corrosion studies were analyzed.
RESULTS
The terms "Riolan arch", "marginal artery of Drummond", "meandering mesenteric artery" and "Villemin's arch" must no longer be used in the scientific literature. Three arterial arches were found at the level of the left colic angle, permitting the communication between the two arterial mesenteric systems: (1) the Marginal Artery (the most peripheral, found in 100% of cases); (2) the "V" termination of the ascending branch of the left colic artery (LCA), existing in more than 2/3 of cases; and (3) the inter-mesenteric trunk, found more centrally located and existing in less than 1/3 of cases.
CONCLUSIONS
Three arterial arches exist at the level of the left colic angle: (1) the Marginal Artery, (2) the "V" termination of the ascending branch of the LCA, and (3) the inter-mesenteric trunk. The knowledge of this anatomy is essential for performing colorectal surgeries involving ligation of the IMA.
Topics: Angiography; Colon; Humans; Mesenteric Artery, Inferior; Mesenteric Artery, Superior
PubMed: 30478643
DOI: 10.1007/s00276-018-2139-5 -
ANZ Journal of Surgery May 2023Traditional siting of stomas, in the lower abdomen, has been guided by surgical dogma lacking evidence. In the lower abdomen, the combination of a thick and pendulous...
BACKGROUND
Traditional siting of stomas, in the lower abdomen, has been guided by surgical dogma lacking evidence. In the lower abdomen, the combination of a thick and pendulous abdominal apron, can create a challenging and suboptimal site for a stoma. The anatomical determinant limiting delivery of a stoma to the abdominal skin is the distance of the SMA from the lower border of the pancreas. The aim of this cross-sectional study was to compare the distance between the traditional stoma site, and upper abdominal stoma sites, to both the superior mesenteric artery (SMA) origin and SMA at the inferior border of the pancreas on abdominal computed tomography (CT).
METHODS
A cross-sectional study at a single academic university hospital of adult patients who underwent abdominal CT in Australia.
RESULTS
Two hundred and thirteen patients were included. Stoma sites in the upper abdomen were 57-76 mm shorter to the origin of the SMA and inferior border of the pancreas than those positioned at the traditional stoma site (P < 0.001). The mean panniculus thickness in the upper abdomen was 10 mm thinner than in the lower abdomen and increased with increasing BMI (P < 0.001). The ratio between the distance from the xiphisternum to umbilicus, and the umbilicus to pubic symphysis, was 1.10; this ratio increased with increasing BMI.
CONCLUSION
The distance of the SMA to the skin is always shorter in the upper abdomen compared to the traditional stoma site. Consideration should be given to placing stomas in the upper abdomen, particularly in overweight or obese patients.
Topics: Adult; Humans; Mesenteric Artery, Superior; Prospective Studies; Cross-Sectional Studies; Mesenteric Arteries; Abdominal Wall
PubMed: 36345119
DOI: 10.1111/ans.18132 -
Frontiers in Bioscience (Landmark... Jun 2022Although the mesenteric artery plays a key role in regulating peripheral blood pressure, the molecular mechanisms that underlie the development of essential hypertension...
BACKGROUND
Although the mesenteric artery plays a key role in regulating peripheral blood pressure, the molecular mechanisms that underlie the development of essential hypertension are not yet fully understood.
MATERIALS AND METHODS
We explored candidate genes for hypertension using three related strains of spontaneously hypertensive rats (SHRs) that mimic human essential hypertension. In this study we used DNA microarrays, a powerful tool for studying genetic diseases, to compare gene expression in the mesenteric artery of three SHR substrains: SHR, stroke-prone SHR (SHRSP), and malignant SHRSP (M-SHRSP).
RESULTS
Compared to normotensive 6-week old Wistar Kyoto rats (WKY), higher blood pressure correlated with overexpression of 31 genes and with down regulation of 24 genes. , which negatively regulates potassium current, and the potassium channel genes, and , were associated with the onset of hypertension. In addition, and were identified as strengtheners of hypertension by analyzing up and down regulated genes at 9-weeks of age.
CONCLUSIONS
, and appear to be factors for the onset of hypertension, while and are as factors that strengthen hypertension. These findings contribute to our understanding of the pathophysiology of hypertension and to the development of treatment for this condition.
Topics: Animals; Blood Pressure; Essential Hypertension; Hypertension; Mesenteric Arteries; Oligonucleotide Array Sequence Analysis; Rats; Rats, Inbred SHR
PubMed: 35748267
DOI: 10.31083/j.fbl2706191 -
Surgical and Radiologic Anatomy : SRA Jul 2023Direct connection between the celiac trunk (CT) and inferior mesenteric artery (IMA) is very rare, knowledge of this anomaly is of great importance to surgeons and... (Review)
Review
PURPOSE
Direct connection between the celiac trunk (CT) and inferior mesenteric artery (IMA) is very rare, knowledge of this anomaly is of great importance to surgeons and anatomists.
INTRODUCTION
Splanchnic arteries arise from the abdominal aorta (AA). Unusual development of these arteries can lead to considerable variations. Historically there were a lot of classification of the variation in the CT and IMA, none of the classifications describes a direct connection from IMA to CT.
MATERIALS AND METHODS
We report a rare case in which the connection between the CT and AA was lost and replaced by a direct anastomosis with IMA.
RESULTS
60 year old male presented to the hospital to undergo a computed tomography scan. Which showed that there was no CT arising from the AA, but there was a large anastomosis arises from the IMA and ended with a short axis and Left gastric artery (LGA), Splenic artery (SA), Common hepatic artery (CHA) arise from this axis, these arteries continued to the stomach and spleen and liver normally. The anastomosis provides the total supply to the CT. The CT branches are normal.
CONCLUSION
Knowledge of the arterial anomalies provides an important help in clinical surgical implications especially in organs transplant.
Topics: Male; Humans; Middle Aged; Aorta, Abdominal; Mesenteric Artery, Inferior; Celiac Artery; Hepatic Artery; Anastomosis, Surgical
PubMed: 37212870
DOI: 10.1007/s00276-023-03169-w -
European Journal of Vascular and... Nov 2022Isolated mesenteric artery dissection (IMAD) is an increasingly diagnosed disease. However, multicentre studies to support clinical decision making are limited. This...
OBJECTIVE
Isolated mesenteric artery dissection (IMAD) is an increasingly diagnosed disease. However, multicentre studies to support clinical decision making are limited. This multicentre retrospective study aimed to investigate the characteristics, treatment options, and outcomes of IMAD.
METHODS
Data from consecutively enrolled patients with IMAD between October 2009 and May 2021 at three hospitals were collected retrospectively. One hundred and ninety uncomplicated symptomatic IMAD patients were divided into two groups: conservative (n = 141) and operative (n = 49). The costs, length of hospital stay, factors affecting outcomes, symptom relief, and complete remodelling of superior mesenteric artery (SMA) were analysed between the two groups.
RESULTS
Compared with patients who received operative treatment, patients receiving conservative treatment had shorter hospital stays (8.2 ± 4.6 vs. 11.9 ± 6.4 day, p < .020) and lower hospital costs (14 900 ± 1 048 vs. 60 400 ± 7 733 yuan, p < .001). In contrast, patients receiving operative treatment showed higher complete SMA remodelling (95.9% vs. 51.8%, p < .001). The cumulative rate of symptom relief was similar between the groups (p = .71). The rates were 78% vs. 79%, 87% vs. 87%, 89% vs. 87% at one, 12, and 60 months in the conservative and operative groups, respectively. Further subgroup analysis showed that endovascular treatment of IMAD had the advantage of shorter hospital stays than open surgery (10.7 ± 4.5 vs. 25.2 ± 9.4 days, p < .010). Univariable analysis showed that Sakamoto type II was associated with failed complete SMA remodelling (odds ratio 0.34; 95% confidence intervals 0.13 - 0.91; p = .031).
CONCLUSION
IMAD patients achieved good long term survival and symptom relief regardless of the treatment. Sakamoto type II IMAD is a risk factor for failed complete SMA remodelling. Although endovascular treatment provided a higher rate of complete SMA remodelling, the conservative group had statistically significantly shorter hospital stays, lower hospital costs, and similar cumulative rates of symptom relief. Therefore, this study supports conservative treatment as the main strategy for uncomplicated symptomatic IMAD patients.
Topics: Humans; Retrospective Studies; Endovascular Procedures; Treatment Outcome; Time Factors; Aortic Dissection; Mesenteric Artery, Superior; Mesenteric Arteries
PubMed: 36038050
DOI: 10.1016/j.ejvs.2022.08.023 -
American Journal of Physiology. Heart... Nov 2019Hydrogen sulfide (HS) dilates isolated arteries, and knockout of the HS-synthesizing enzyme cystathionine γ-lyase (CSE) increases blood pressure. However, the... (Comparative Study)
Comparative Study
Hydrogen sulfide (HS) dilates isolated arteries, and knockout of the HS-synthesizing enzyme cystathionine γ-lyase (CSE) increases blood pressure. However, the contributions of endogenously produced HS to blood flow regulation in specific vascular beds are unknown. Published studies in isolated arteries show that CSE production of HS influences vascular tone more in small mesenteric arteries than in renal arteries or the aorta. Therefore, the goal of this study was to evaluate HS regulation of blood pressure, vascular resistance, and regional blood flows using chronically instrumented rats. We hypothesized that during whole animal CSE inhibition, vascular resistance would increase more in the mesenteric than the renal circulation. Under anesthesia, CSE inhibition [β-cyanoalanine (BCA), 30 mg/kg bolus + 5 mg·kg·min for 20 min iv) rapidly increased mean arterial pressure (MAP) more than saline administration (%Δ: saline -1.4 ± 0.75 vs. BCA 7.1 ± 1.69, < 0.05) but did not change resistance (MAP/flow) in either the mesenteric or renal circulation. In conscious rats, BCA infusion similarly increased MAP (%Δ: saline -0.8 ± 1.18 vs. BCA 8.2 ± 2.6, < 0.05, = 7) and significantly increased mesenteric resistance (saline 0.9 ± 3.1 vs. BCA 15.6 ± 6.5, < 0.05, = 12). The HS donor NaS (50 mg/kg) decreased blood pressure and mesenteric resistance ,but the fall in resistance was not significant. Inhibiting CSE for multiple days with dl-proparglycine (PAG, 50 mg·kg·min iv bolus for 5 days) significantly increased vascular resistance in both mesenteric (ratio of : saline 0.86 ± 0.033 vs. PAG 1.79 ± 0.38) and renal circulations (ratio of : saline 1.26 ± 0.22 vs. 1.98 ± 0.14 PAG). These results support our hypothesis that CSE-derived HS is an important regulator of blood pressure and vascular resistance in both mesenteric and renal circulations. Furthermore, inhalation anesthesia diminishes the effect of CSE inhibition on vascular tone. These results suggest that CSE-derived HS has a prominent role in regulating blood pressure and blood flow under physiological conditions, which may have been underestimated in prior studies in anesthetized subjects. Therefore, enhancing substrate availability or enzyme activity or dosing with HS donors could be a novel therapeutic approach to treat cardiovascular diseases.
Topics: Alanine; Animals; Arterial Pressure; Blood Flow Velocity; Cystathionine gamma-Lyase; Enzyme Inhibitors; Hydrogen Sulfide; Male; Mesenteric Arteries; Rats, Sprague-Dawley; Renal Artery; Renal Circulation; Splanchnic Circulation; Sulfides; Vascular Resistance
PubMed: 31625777
DOI: 10.1152/ajpheart.00303.2019 -
Methods in Molecular Biology (Clifton,... 2019Isolated tissue chamber bath system and wire myograph were developed for "in vitro" investigation of vasoactive responses on isolated arteries from a variety of animal...
Isolated tissue chamber bath system and wire myograph were developed for "in vitro" investigation of vasoactive responses on isolated arteries from a variety of animal species and vascular beds. The chapter characterizes the main principles of mechanical measurement of the changes in isometric tension of vascular smooth muscles in isolated rat thoracic aorta and superior mesenteric artery and describes several protocols on how to investigate vasoactive properties of hydrogen sulfide (HS) from the point of view of its mutual interaction with NO. Several methodological advances, results, and their interpretations in the context of the general knowledge are described. In the protocols the approach on how to study the vasoactive modulatory as well as direct action of HS and mutual interaction of HS with nitroso compounds, lipids, and endogenously produced NO is described.
Topics: Animals; Aorta, Thoracic; Hydrogen Sulfide; Mesenteric Arteries; Muscle, Smooth, Vascular; Nitric Oxide; Rats; Rats, Inbred SHR; Rats, Wistar; Vasodilation
PubMed: 31148108
DOI: 10.1007/978-1-4939-9528-8_7