Morph‐anatomic and histochemical study of ileum of goose ( Alopochen egyptiacus ) with special references to immune cells, mucous and serous goblet cells, telocytes, and dark and light smooth muscle fibers

AbstractUniaxial tensile experiments are a standard method to determine the contractile properties of smooth muscles. Smooth muscle strips from organs of the urogenital and gastrointestinal tract contain multiple muscle layers with different muscle fiber orientations, which are frequently not separated for the experiments. During strip activation, these muscle fibers contract in deviant orientations from the force-measuring axis, affecting the biomechanical characteristics of the tissue strips. This study aimed to investigate the influence of muscle layer separation on the determination of smooth muscle properties. Smooth muscle strips, consisting of longitudinal and circumferential muscle layers (whole-muscle strips [WMS]), and smooth muscle strips, consisting of only the circumferential muscle layer (separated layer strips [SLS]), have been prepared from the fundus of the porcine stomach. Strips were mounted with muscle fibers of the circumferential layer inline with the force-measuring axis of the uniaxial testing setup. The force–length (FLR) and force–velocity relationships (FVR) were determined through a series of isometric and isotonic contractions, respectively. Muscle layer separation revealed no changes in the FLR. However, the SLS exhibited a higher maximal shortening velocity and a lower curvature factor than WMS. During WMS activation, the transversally oriented muscle fibers of the longitudinal layer shortened, resulting in a narrowing of this layer. Expecting volume constancy of muscle tissue, this narrowing leads to a lengthening of the longitudinal layer, which counteracted the shortening of the circumferential layer during isotonic contractions. Consequently, the shortening velocities of the WMS were decreased significantly. This effect was stronger at high shortening velocities.

Download Full-text

Possible Crosstalk of the Immune Cells within the Lung and Mediastinal Fat-Associated Lymphoid Clusters in the Acute Inflammatory Lung Asthma-Like Mouse Model

International Journal of Molecular Sciences ◽

10.3390/ijms22136878 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6878

Author(s):

Yaser Hosny Ali Elewa ◽

Mahmoud Mansour Abd Elwakil ◽

Osamu Ichii ◽

Teppei Nakamura ◽

Sherif Kh. A. Mohamed ◽

...

Keyword(s):

Mouse Model ◽

Immune Cells ◽

Phosphate Buffer ◽

Respiratory Diseases ◽

Critical Role ◽

Goblet Cells ◽

Vehicle Group ◽

Natural Helper ◽

B And T Lymphocytes ◽

Intranasal Instillation

Recently, we clarified the function of mediastinal fat-associated lymphoid clusters (MFALCs) in the progression of several respiratory diseases. However, their role has not yet been identified in the lung asthmatic condition. Hence, we compared the immune cells in lung and MFALCs of C57BL/6N mice on days 3 and 7 following intranasal instillation of either papain (papain group “PG”) or phosphate buffer saline (PBS) (vehicle group “VG”). The PG showed significantly prominent MFALCs, numerous goblet cells (GCs), and higher index ratios of different immune cells (macrophages, natural helper cells (NHC), B- and T-lymphocytes) within the MFALCs and lung than in the VG on both days 3 and 7. Interestingly, a tendency of decreased size of MFALCs and a significant reduction in the number of GCs and immune cells were observed within the MFALCs and lung in the PG on day 7 than on day 3. Furthermore, the quantitative parameters of these immune cells in MFALCs were significantly and positively correlated with the size of MFALCs and immune cells in the lung. This suggested that the possible crosstalk between immune cells within MFALCs and the lung could play a critical role in the progression and recovery of the acute inflammatory lung asthma.

Download Full-text

Effect of Experimentally Induced Chronic Kidney disease on Skeletal, Cardiac and Smooth Muscle fibers of albino rat

QJM ◽

10.1093/qjmed/hcab099.006 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Ghada Lotfy ◽

Amel Soliman ◽

Nevine Bahaa ◽

Mohammed Hegazi

Keyword(s):

Skeletal Muscle ◽

Chronic Kidney Disease ◽

Smooth Muscle ◽

Kidney Disease ◽

Intramuscular Injection ◽

Muscle Fibers ◽

Lateral Wall ◽

Control Group ◽

Once Daily ◽

Group Ii

Abstract Background Chronic kidney disease (CKD), or chronic renal failure (CRF) as it was historically termed, includes all degrees of decreased renal function, starting from mild, and moderate, to severe chronic kidney failure. Skeletal muscle atrophy frequently complicates the course of CKD and is associated with excess morbidity and mortality. Cardiovascular diseases have been reported to be the leading causes of death in CKD patients. Chronic Kidney Disease was also reported to be associated with an increased incidence of acid-related gastrointestinal disorders. Aim of the work The aim of this study was to investigate the effect of chronic kidney disease experimentally induced by gentamicin intramuscular injection on the histological structure of gastrocnemius skeletal muscle, left ventricular cardiac muscle and smooth muscle fibers of lower esophagus. Materials and methods Twenty male adult Wistar albino rats were randomly and equally divided into two groups. Group I (control group) received physiological saline intramuscular injection, once daily for 28 consecutive days, in a dose equivalent to that taken in group II. Group II (Gentamicin-treated group) were given Gentamicin intramuscular injection for induction of CKD. Gentamicin was given as Gentamycin sulfate, 40 mg/ml (Sandoz, Switzerland), once daily, in a dose of 80 mg/kg/day for 28 days to induce CKD. After 28 days of the first injection of gentamicin, rats were anaesthetized and blood samples were collected to measure the level of serum urea and creatinine. The left kidneys, the middle third of left gastrocnemius muscle, the lateral wall of left ventricle (LV) and the gastroesophageal junction of all rats of both groups (I and II) were processed for light microscopic study. The middle third of left gastrocnemius muscle, the lateral wall of left ventricle (LV) were further processed for transmission electron microscopic study. Histomorphometrical and statistical analysis were also done. Results The LM examination revealed moderate obliteration of glomeruli, dilatation in some renal tubules and collapse in others, mainly in distal convoluted tubules, with significant fibrosis of renal parenchyma. Serum urea and creatinine levels were increased significantly. The skeletal muscle fibers of the rats in group II (CKD) showed focal areas of myofibers degeneration with siginificant fibrosis. The cardiac muscle fibers of the rats in the group II (CKD) showed focal areas of cardiomyocytes degeneration and other areas of significantly hypertrophied fibers. The smooth muscle fibers of the lower esophageal sphincter of the rats in group II (CKD) showed no significant structural changes compared with the control group, however, the myenetric plexus showed multiple pyknotic and karyolitic nuclei with vacuolated cytoplasm. In addition, insignificant increase in the amount of collagen fibers was observed in almost all layers. Conclusion CKD produced moderate atrophy of skeletal muscle fibers, significant increase in the cardiomyocyte size and no significant structural effect of smooth muscle fibers of the lower esophageal sphincter.

Download Full-text

Smooth muscles from spastic coronary artery segments show hypercontractility to histamine

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1990.259.1.h9 ◽

1990 ◽

Vol 259 (1) ◽

pp. H9-H13 ◽

Cited By ~ 2

Author(s):

S. Satoh ◽

H. Tomoike ◽

W. Mitsuoka ◽

S. Egashira ◽

H. Tagawa ◽

...

Keyword(s):

Smooth Muscle ◽

Coronary Artery ◽

Coronary Arteries ◽

Muscle Fibers ◽

Coronary Spasm ◽

Smooth Muscles ◽

Bolus Administration ◽

Luminal Diameter ◽

Endothelial Denudation ◽

Significant Difference

An animal model of coronary spasm was produced in Gottingen miniature pigs by a selective endothelial denudation of the coronary artery. Five months after the denudation, intracoronary bolus administration of 10 micrograms/kg histamine reduced the luminal diameter angiographically by 57 +/- 16 and 17 +/- 10% (P less than 0.01) in the previously denuded and contralateral control coronary arteries. Muscle fibers of 0.08–0.1 mm wide were prepared from circumferential bundles of the medial smooth muscle in the spastic and nonspastic coronary arteries. Upward shifts of either dose-tonic contraction relationships in Ca2(+)-containing solution or dose-monophasic contraction relationships in Ca2(+)-free solution were noted in muscle fibers taken from the spastic site compared with those from the nonspastic site with no difference between the mean effective dose values. After skinning the muscle fibers with saponin, there was no significant difference in the Ca2+ concentration-tension relationships between the two fibers. These findings suggest that an increased number of histaminergic receptors and/or augmentation of signal transduction, but not Ca2+ sensitivity of the contractile proteins in the medial smooth muscle cells, cause histamine-induced coronary hypercontraction.

Download Full-text

Clinical and morphological features of scar tissue of the uterus.

Reports of Vinnytsia National Medical University ◽

10.31393/reports-vnmedical-2019-23(1)-16 ◽

2019 ◽

Vol 23 (1) ◽

pp. 98-103

Author(s):

N.P. Goncharuk ◽

N.R. Kovyda ◽

O.O. Dyadyk ◽

Y.S. Radkevich

Keyword(s):

Smooth Muscle ◽

Muscle Fibers ◽

Fibrous Tissue ◽

Significant Proportion ◽

Scar Tissue ◽

Vaginal Birth ◽

Pathological Changes ◽

Smooth Muscle Tissue ◽

Uterine Scar ◽

Group 1

One of the key issues for increase uterine scars is the rapid and unwarranted Caesarean sections (CS) as in the world same in Ukraine. One of the way to reduce CS is delivery truth vaginal births in women with previous surgical intervention on the uterus or after CS. The ability of scar on the uterus is the main criterion for an attempt to vaginal birth. Objectivе — to analyze the structural changes of the scar tissue of the uterus. Pathomorphological examination was fragments of uterus scar. The material was fixed in a 10% solution of neutral colored formalin (pH 7.4) carried out according to the standard procedure, poured into paraffin. From the paraffin blocks on the rotary microtome of HM 325, serial histological sections were made in a thickness of 4–5 microns, which were stained with hematoxylin and eosin. Scar tissue was additionally stained for Van Gieson, according to Masson. Fragments of scar tissue were subjected to an immunohistochemical study (IGHS) using monoclonal antibodies (MATs) to CD31 to assess the degree of vascularization vascular component and α-SMA for assessing the condition smooth muscle tissue. Having conducted a comprehensive pathomorphological study in two groups, one can state that in group 1 the pathomorphological picture of the changes in the scar was minimal and confirmed by the retained proportions between the fibrous tissue and the smooth muscle fibers, as well as their characteristic location. Muscle fibers with minimal pathological changes, developed by compensatory changes from the side of the vascular complex. These data were confirmed by conducting IGHS from MAT to CD31, which gives a pronounced positive response in the endothelial layer of the vascular wall, forming continuous cell chains. IGHS from MAT to α-SMA exhibits pronounced homogeneous intensive expression, indicating minimal pathological changes in muscle fibers. These figures make it possible to talk about the ability of uterine scar in 61% in group 1, as opposed to in group 2, this result was only 41%. As a result of a comprehensive clinical and morphological study, it was found that the majority of women in group 1, according to the morphological and histological characteristics, had a capable scar on the uterus, that is, potentially could be considered as a reserve for vaginal birth in women with uterine scar after the previous CS. In the second group, a significant proportion of women confirmed the correlation of regenerative and degenerative changes in the tissues of postoperative scar, indicating prevalence of fibro-sclerotic changes and insufficient vascularization, that is, it states the validity of operational resolution.

Download Full-text

Abstract 15539: Single-cell Analysis of Aortic Tissues From Patients With Marfan Syndrome Reveals Changes in Smooth Muscle Cell Differentiation

Circulation ◽

10.1161/circ.142.suppl_3.15539 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Ashley Dawson ◽

Yanming Li ◽

Pingping Ren ◽

Hernan Vasquez ◽

Chen Zhang ◽

...

Keyword(s):

Smooth Muscle ◽

Single Cell ◽

Marfan Syndrome ◽

Immune Cells ◽

Matrix Protein ◽

Immune Cell ◽

Aortic Aneurysms ◽

Extracellular Matrix Protein ◽

Cardiac Transplant ◽

Control Tissue

Background: Thoracic aortic aneurysms associated with Marfan syndrome (MFS) carry a high risk of mortality; however, the molecular and cellular processes leading to aortopathy in this population remain poorly understood. We aimed to use single-cell RNA (scRNA) sequencing to define the non-immune cell populations present within the aortic wall in MFS, hypothesizing that these would differ from those of non-aneurysmal control tissue. Methods: We performed scRNA sequencing of ascending aortic aneurysm tissues from MFS patients (n=3) undergoing aneurysm repair and of age-matched, non-aneurysmal control tissue from cardiac transplant donors and recipients (n=4). The Seurat package in R was used for analysis. Differentially expressed genes were identified using edgeR. Results: Eighteen non-immune cell clusters were identified, with conserved gene expression of the largest of the clusters consistent with smooth muscle cells (SMCs; n=6), fibroblasts (n=3), and endothelial cells (n=3). The SMCs and fibroblasts exhibited graded changes in their expression of contractile and extracellular matrix protein genes, supportive of a phenotypic continuum. Additionally, we identified differences in the proportions of non-immune cells in MFS tissues compared to controls. In control tissues, the most common non-immune cells expressed markers of contractile SMC maturity including CNN1 , MYH11 , and SMTN . In contrast, the largest clusters in MFS tissue were most closely related to SMCs on correlation analysis, but displayed increased expression of cyclin genes as well as immune, endothelial, and fibroblast genes indicative of de-differentiated, proliferative SMCs. Additionally, expression of genes associated with SMC phenotypic maturity, including MYH11 and MYOCD , were significantly downregulated in several of the MFS SMC clusters. Conclusion: Our data demonstrate a phenotypic continuum between fibroblasts and SMCs, with aortas from patients with MFS exhibiting an increased proportion of de-differentiated, proliferative SMCs compared to controls. Additionally, markers of SMC maturity were downregulated in SMCs in MFS compared to controls. This may be due to disruption of signaling pathways that promote differentiation.

Download Full-text