Fibronectin and cell shape in vivo: studies on the endometrium during pregnancy.

The rat endometrium during pregnancy was used as a model system to study fibronectin in vivo. Fibronectin distribution on stromal fibroblasts, as determined by indirect immunofluorescence staining, was studied in relationship to cell shape during decidual transformation. Fibroblasts of the estrus endometrial stroma were elongated cells with a fibrillar pattern of fibronectin on their surfaces. During days 1-6 of pregnancy, as these elongated cells acquired a round morphology, fibronectin changed first to a patched distribution on the cells'a surfaces and then disappeared. The change in fibronectin was specific for the fibroblasts since over the same time period there was no decrease in fibronectin found associated with blood vessels or in the epithelial-stromal basement membrane. These results support the proposed relationship between cell surface fibronectin and cell shape that has been inferred from in vitro experiments. After implantation, fibronectin distribution was studied in relationship to the position of the conceptus. In the stroma proximal to the implanting conceptus, fibronectin was absent except around blood vessels, which may help explain how decidual tissue could act as a barrier to trophoblast invasion. Finally, fibronectin distribution was studied in the uterus after parturition. Debris in the uterine lumen was coated with fibronectin, which may be important in the rapid removal of this material by phagocytic cells. Also, fibronectin associated with the epithelial-stromal basement membrane was reorganized after reepithelialization had occurred.

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Amylin: Localization, Effects on Cerebral Arteries and on Local Cerebral Blood Flow in the Cat

The Scientific World JOURNAL ◽

10.1100/tsw.2001.23 ◽

2001 ◽

Vol 1 ◽

pp. 168-180 ◽

Cited By ~ 33

Author(s):

Lars Edvinsson ◽

Peter J. Goadsby ◽

Rolf Uddman

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Blood Vessels ◽

Cerebral Arteries ◽

In Vivo Studies ◽

Cerebral Blood Vessels ◽

Local Cerebral Blood Flow ◽

Doppler Flowmetry

Amylin and adrenomedullin are two peptides structurally related to calcitonin gene-related peptide (CGRP). We studied the occurrence of amylin in trigeminal ganglia and cerebral blood vessels of the cat with immunocytochemistry and evaluated the role of amylin and adrenomedullin in the cerebral circulation by in vitro and in vivo pharmacology. Immunocytochemistry revealed that numerous nerve cell bodies in the trigeminal ganglion contained CGRP immunoreactivity (-ir); some of these also expressed amylin-ir but none adrenomedullin-ir. There were numerous nerve fibres surrounding cerebral blood vessels that contained CGRP-ir. Occasional fibres contained amylin-ir while we observed no adrenomedullin-ir in the vessel walls. With RT-PCR and Real-Time�PCR we revealed the presence of mRNA for calcitonin receptor-like receptor (CLRL) and receptor-activity-modifying proteins (RAMPs) in cat cerebral arteries. In vitro studies revealed that amylin, adrenomedullin, and CGRP relaxed ring segments of the cat middle cerebral artery. CGRP and amylin caused concentration-dependent relaxations at low concentrations of PGF2a-precontracted segment (with or without endothelium) whereas only at high concentration did adrenomedullin cause relaxation. CGRP8-37 blocked the CGRP and amylin induced relaxations in a parallel fashion. In vivo studies of amylin, adrenomedullin, and CGRP showed a brisk reproducible increase in local cerebral blood flow as examined using laser Doppler flowmetry applied to the cerebral cortex of the a-chloralose�anesthetized cat. The responses to amylin and CGRP were blocked by CGRP8-37. The studies suggest that there is a functional sub-set of amylin-containing trigeminal neurons which probably act via CGRP receptors.

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Mg2+–Ca2+ interaction in contractility of vascular smooth muscle: Mg2+ versus organic calcium channel blockers on myogenic tone and agonist-induced responsiveness of blood vessels

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y87-120 ◽

1987 ◽

Vol 65 (4) ◽

pp. 729-745 ◽

Cited By ~ 174

Author(s):

B. M. Altura ◽

B. T. Altura ◽

A. Carella ◽

A. Gebrewold ◽

T. Murakawa ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Blood Vessels ◽

Divalent Cations ◽

Smooth Muscles ◽

In Vivo Studies ◽

Channel Blockers ◽

Arterial Blood

Contractility of all types of invertebrate and vertebrate muscle is dependent upon the actions and interactions of two divalent cations, viz., calcium (Ca2+) and magnesium (Mg2+) ions. The data presented and reviewed herein contrast the actions of several organic Ca2+ channel blockers with the natural, physiologic (inorganic) Ca2+ antagonist, Mg2+, on microvascular and macrovascular smooth muscles. Both direct in vivo studies on microscopic arteriolar and venular smooth muscles and in vitro studies on different types of blood vessels are presented. It is clear from the studies done so far that of all Ca2+ antagonists examined, only Mg2+ has the capability to inhibit myogenic, basal, and hormonal-induced vascular tone in all types of vascular smooth muscle. Data obtained with verapamil, nimopidine, nitrendipine, and nisoldipine on the microvasculature are suggestive of the probability that a heterogeneity of Ca2+ channels, and of Ca2+ binding sites, exists in different microvascular smooth muscles; although some appear to be voltage operated and others, receptor operated, they are probably heterogeneous in composition from one vascular region to another. Mg2+ appears to act on voltage-, receptor-, and leak-operated membrane channels in vascular smooth muscle. The organic Ca2+ channel blockers do not have this uniform capability; they demonstrate a selectivity when compared with Mg2+. Mg2+ appears to be a special kind of Ca2+ channel antagonist in vascular smooth muscle. At vascular membranes it can (i) block Ca2+ entry and exit, (ii) lower peripheral and cerebral vascular resistance, (iii) relieve cerebral, coronary, and peripheral vasospasm, and (iv) lower arterial blood pressure. At micromolar concentrations (i.e., 10–100 μM), Mg2+ can cause significant vasodilatation of intact arterioles and venules in all regional vasculatures so far examined. Although Mg2+ is three to five orders of magnitude less potent than the organic Ca2+ channel blockers, it possesses unique and potentially useful Ca2+ antagonistic properties.

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Advanced in Molecular Mechanisms of Atherosclerosis: From Lipids to Inflammation

The Indonesian Biomedical Journal ◽

10.18585/inabj.v10i2.479 ◽

2018 ◽

Vol 10 (2) ◽

pp. 104-22 ◽

Cited By ~ 1

Author(s):

Anna Meiliana ◽

Nurrani Mustika Dewi ◽

Andi Wijaya

Keyword(s):

Vascular Disease ◽

Blood Vessels ◽

Molecular Mechanisms ◽

Vascular Dysfunction ◽

In Vivo Studies ◽

Disease States ◽

Fibrous Cap ◽

Plaque Disruption

BACKGROUND: Atherosclerosis is a leading cause of vascular disease worldwide. During the past several decades, landmark discoveries in the field of vascular biology have evolved our understanding of the biology of blood vessels and the pathobiology of local and systemic vascular disease states and have led to novel disease-modifying therapies for patients. This review is made to understand the molecular mechanism of atherosclerosis for these future therapies.CONTENT: Advances in molecular biology and -omics technologies have facilitated in vitro and in vivo studies which revealed that blood vessels regulate their own redox milieu, metabolism, mechanical environment, and phenotype, in part, through complex interactions between cellular components of the blood vessel wall and circulating factors. Dysregulation of these carefully orchestrated homeostatic interactions has also been implicated as the mechanism by which risk factors for cardiopulmonary vascular disease lead to vascular dysfunction, structural remodeling and, ultimately, adverse clinical events.SUMMARY: Atherosclerosis is a heterogeneous disease, despite a common initiating event of apoB-lipoproteins. Despite of acute thrombotic complications, an adequate resolution response is mounted, where efferocytosis prevents plaque necrosis and a reparative scarring response (the fibrous cap) prevents plaque disruption. However, a small percentage of developing atherosclerotic lesions cannot maintain an adequate resolution response, which leading to the formation of clinically dangerous plaques that can trigger acute lumenal thrombosis and tissue ischemiaand infarction.KEYWORDS: atherosclerosis, oxidative stress, inflammation, efferocytosis, foam cells, thrombosis

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Adhesive and degradative properties of human placental cytotrophoblast cells in vitro.

The Journal of Cell Biology ◽

10.1083/jcb.109.2.891 ◽

1989 ◽

Vol 109 (2) ◽

pp. 891-902 ◽

Cited By ~ 323

Author(s):

S J Fisher ◽

T Y Cui ◽

L Zhang ◽

L Hartman ◽

K Grahl ◽

...

Keyword(s):

Basement Membrane ◽

First Trimester ◽

Late Gestation ◽

Trophoblast Invasion ◽

Third Trimester ◽

Biochemical Basis ◽

Teratocarcinoma Cell ◽

Cytotrophoblast Cells

Human fetal development depends on the embryo rapidly gaining access to the maternal circulation. The trophoblast cells that form the fetal portion of the human placenta have solved this problem by transiently exhibiting certain tumor-like properties. Thus, during early pregnancy fetal cytotrophoblast cells invade the uterus and its arterial network. This process peaks during the twelfth week of pregnancy and declines rapidly thereafter, suggesting that the highly specialized, invasive behavior of the cytotrophoblast cells is closely regulated. Since little is known about the actual mechanisms involved, we developed an isolation procedure for cytotrophoblasts from placentas of different gestational ages to study their adhesive and invasive properties in vitro. Cytotrophoblasts isolated from first, second, and third trimester human placentas were plated on the basement membrane-like extracellular matrix produced by the PF HR9 teratocarcinoma cell line. Cells from all trimesters expressed the calcium-dependent cell adhesion molecule cell-CAM 120/80 (E-cadherin) which, in the placenta, is specific for cytotrophoblasts. However, only the first trimester cytotrophoblast cells degraded the matrices on which they were cultured, leaving large gaps in the basement membrane substrates and releasing low molecular mass 3H-labeled matrix components into the medium. No similar degradative activity was observed when second or third trimester cytotrophoblast cells, first trimester human placental fibroblasts, or the human choriocarcinoma cell lines BeWo and JAR were cultured on radiolabeled matrices. To begin to understand the biochemical basis of this degradative behavior, the substrate gel technique was used to analyze the cell-associated and secreted proteinase activities expressed by early, mid, and late gestation cytotrophoblasts. Several gelatin-degrading proteinases were uniquely expressed by early gestation, invasive cytotrophoblasts, and all these activities could be abolished by inhibitors of metalloproteinases. By early second trimester, the time when cytotrophoblast invasion rapidly diminishes in vivo, the proteinase pattern of the cytotrophoblasts was identical to that of term, noninvasive cells. These results are the first evidence suggesting that specialized, temporally regulated metalloproteinases are involved in trophoblast invasion of the uterus. Since the cytotrophoblasts from first trimester and later gestation placentas maintain for several days the temporally regulated degradative behavior displayed in vivo, the short-term cytotrophoblast outgrowth culture system described here should be useful in studying some of the early events in human placen

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Basement membrane-like structures containing NTH α1(IV) are formed around the endothelial cell network in a novel in vitro angiogenesis model

AJP Cell Physiology ◽

10.1152/ajpcell.00353.2018 ◽

2019 ◽

Vol 317 (2) ◽

pp. C314-C325

Author(s):

Yongchol Shin ◽

Akane Moriya ◽

Yuta Tohnishi ◽

Takafumi Watanabe ◽

Yasutada Imamura

Keyword(s):

Endothelial Cells ◽

Basement Membrane ◽

Blood Vessels ◽

Type Iv Collagen ◽

Vascular Endothelial Cells ◽

Culture Dish ◽

Cell Network ◽

Type Iv

Angiogenesis is a process through which new blood vessels are formed by sprouting and elongating from existing blood vessels. Several methods have been used to replicate angiogenesis in vitro, including culturing vascular endothelial cells on Matrigel and coculturing with endothelial cells and fibroblasts. However, the angiogenesis elongation process has not been completely clarified in these models. We therefore propose a new in vitro model of angiogenesis, suitable for observing vascular elongation, by seeding a spheroid cocultured from endothelial cells and fibroblasts into a culture dish. In this model, endothelial cells formed tubular networks elongated from the spheroid with a lumen structure and were connected with tight junctions. A basement membrane (BM)-like structure was observed around the tubular network, similarly to blood vessels in vivo. These results suggested that blood vessel-like structure could be reconstituted in our model. Laminin and type IV collagen, main BM components, were highly localized around the network, along with nontriple helical form of type IV collagen α1-chain [NTH α1(IV)]. In an ascorbic acid-depleted condition, laminin and NTH α1(IV) were observed around the network but not the triple-helical form of type IV collagen and the network was unstable. These results suggest that laminin and NTH α1(IV) are involved in the formation of tubular network and type IV collagen is necessary to stabilize the network.

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Action of Dation 500 mg on the Principal Inflammatory Mediators

Phlebology The Journal of Venous Disease ◽

10.1177/0268355594009001s11 ◽

1994 ◽

Vol 9 (1_suppl) ◽

pp. 34-39 ◽

Cited By ~ 7

Author(s):

L. Lerond

Keyword(s):

Inflammatory Mediators ◽

Human Fibroblasts ◽

In Vitro Models ◽

Diabetic Rats ◽

In Vivo Studies ◽

Plasma Extravasation ◽

Phagocytic Cells ◽

Chronic Inflammatory Condition

Objective: To review the in vivo and in vitro studies having elicited an action of Daflon 500 mg*, a purified micronized flavonoid fraction, on inflammatory processes. Design: Antioedematous and antichemotactic effects were investigated in rats in three studies. Moreover, the effect of Daflon 500 mg on free radicals, lipoperoxide and arachidonic acid metabolites known as inflammatory mediators was studied mainly in vitro to help understand mechanisms responsible for the anti-inflammatory activity. Results: The in vivo studies demonstrated that at the single oral dose of 100 mg/kg, Daflon 500 mg inhibited oedema induced by carrageenan injection into the plantar tissue of a hind paw. On a more chronic inflammatory condition, administered at the same dose during the 15 days preceding subcutaneous implantation of sponges and continued until sacrifice, it reduced granuloma weights (reflecting plasma extravasation) and density of phagocytic cells, and at a dose of 300 mg/kg/day for 1 month it mitigated mononuclear infiltration in the pancreas of diabetic rats. On the other hand, Daflon 500 mg in vitro elicited antiradical activity by inhibition of chemiluminesence, inhibited lipid peroxidation induced after hypoxia/reoxygenation in bovine aorto-endothelial cells and after UVA exposure in human fibroblasts. Besides, Daflon 500 mg decreased leukotriene production in rat stimulated mast cells as well as prostaglandins (PGE2, PGF2α) and thromboxane (TxB2) in a granuloma model. Conclusion: The effects of Daflon 500 mg on experimental oedema probably result from interference with inflammatory mediators as demonstrated using in vivo and in vitro models, and may serve as a rational basis to explain its efficacy in diseases such as chronic venous insufficiency and more specifically in haemorrhoidal attacks.

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Traversing the basement membrane in vivo: A diversity of strategies

The Journal of Cell Biology ◽

10.1083/jcb.201311112 ◽

2014 ◽

Vol 204 (3) ◽

pp. 291-302 ◽

Cited By ~ 105

Author(s):

Laura C. Kelley ◽

Lauren L. Lohmer ◽

Elliott J. Hagedorn ◽

David R. Sherwood

Keyword(s):

Extracellular Matrix ◽

Basement Membrane ◽

Metastatic Disease ◽

Tissue Level ◽

In Vitro Studies ◽

In Vivo Studies ◽

Leukocyte Trafficking ◽

Diverse Range

The basement membrane is a dense, highly cross-linked, sheet-like extracellular matrix that underlies all epithelia and endothelia in multicellular animals. During development, leukocyte trafficking, and metastatic disease, cells cross the basement membrane to disperse and enter new tissues. Based largely on in vitro studies, cells have been thought to use proteases to dissolve and traverse this formidable obstacle. Surprisingly, recent in vivo studies have uncovered a remarkably diverse range of cellular- and tissue-level strategies beyond proteolysis that cells use to navigate through the basement membrane. These fascinating and unexpected mechanisms have increased our understanding of how cells cross this matrix barrier in physiological and disease settings.

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