cGMP-and cAMP-modulated calcium binding by the myocardial sarcolemma in circulatory hypoxia

1986 ◽  
Vol 102 (4) ◽  
pp. 1358-1360
Author(s):  
E. V. Sviderskaya ◽  
A. E. Antipenko ◽  
S. N. Lyzlova
Keyword(s):  
Calcium Binding ◽  
Circulatory Hypoxia

Immunogold localization of calmodulin in root caps of the maize Cultivar Merit

1990 ◽  
Vol 48 (3) ◽  
pp. 674-675
Author(s):  
P.T. Nguyen ◽  
C. Uphoff ◽  
C.L. Stinemetz
Keyword(s):  
Calcium Binding ◽  
Calcium Transport ◽  
Primary Role ◽  
Immunogold Localization ◽  
Root Tips ◽  
Electrical Currents ◽  
Considerable Evidence ◽  
Maize Cultivar ◽  
Gravity Response ◽  
Induced Changes

Considerable evidence suggest that the calcium-binding protein calmodulin (CaM) may mediate calcium action and/or transport important in the gravity response of plants. Calmodulin is present in both shoots and roots and is capable of regulating calcium transport in plant vesicles. In roots calmodulin is concentrated in the tip, the gravisensing region of the root; and is reported to be closely associated with amyloplasts, organelles suggested to play a primary role in gravi-perception. Inhibitors of CaM such as chlorpromazine, calmidazolium, and compound 48/80 interfere with the gravitropic response of both snoots and roots. The magnitude of the inhibition corresponded well with the extent to which the drug binds to endogenous CaM. Compound 48/80 and calmidazolium block gravi-induced changes in electrical currents across root tips, a phenomenon thought to be associated with the sensing of the gravity stimulus.In this study, we have investigated the subcellular distribution of CaM in graviresponsive and non-graviresponsive root caps of the maize cultivar Merit.

Immunogold labeling of the calcium binding protein synexin in isolated adrenal chromaffin granules and chromaffin cells

1990 ◽  
Vol 48 (3) ◽  
pp. 952-953
Author(s):  
Gemma A.J. Kuijpers ◽  
Harvey B. Pollard
Keyword(s):  
Adrenal Medulla ◽  
Calcium Binding ◽  
Chromaffin Cells ◽  
Cell Activation ◽  
Structural Information ◽  
Dependent Manner ◽  
Chromaffin Granules ◽  
Immuno Electron Microscopy ◽  
Ultrathin Sections ◽  
Adrenal Chromaffin

Exocytotic fusion of granules in the adrenal medulla chromaffin cell is triggered by a rise in the concentration of cytosolic Ca2+ upon cell activation. The protein synexin, annexin VII, was originally found in the adrenal medulla and has been shown to cause aggregation and to support fusion of chromaffin granules in a Ca2+-dependent manner. We have previously suggested that synexin may there fore play a role in the exocytotic fusion process. In order to obtain more structural information on synexin, we performed immuno-electron microscopy on frozen ultrathin sections of both isolated chromaffin granules and chromaffin cells.Chromaffin granules were isolated from bovine adrenal medulla, and synexin was isolated from bovine lung. Granules were incubated in the presence or absence of synexin (24 μg per mg granule protein) and Ca2+ (1 mM), which induces maximal granule aggregation, in 0.3M sucrose-40m MMES buffer(pH 6.0). Granules were pelleted, washed twice in buffer without synexin and fixed with 2% glutaraldehyde- 2% para formaldehyde in 0.1 M phosphate buffer (GA/PFA) for 30 min. Chromaffin cells were isolated and cultured for 3-5 days, and washed and incubated in Krebs solution with or without 20 uM nicotine. Cells were fixed 90 sec after on set of stimulation with GA/PFA for 30 min. Fixed granule or cell pellets were washed, infiltrated with 2.3 M sucrose in PBS, mounted and frozen in liquid N2.

A New Concept of the Pathogenesis of Retinopathy of Prematurity

2020 ◽  
pp. 5-12
Author(s):  
E.I. Sidorenko ◽  
Keyword(s):  
Growth Factors ◽  
Retinopathy Of Prematurity ◽  
Vascular Endothelium ◽  
Retinal Vessels ◽  
Protective Mechanisms ◽  
Preclinical Stage ◽  
Circulatory Hypoxia ◽  
Preclinical Phase ◽  
Vasculogenesis And Angiogenesis ◽  
Vascular Autoregulation

The lecture provides a detailed description of the development of retinal vessels, vasculogenesis and angiogenesis. The cascade of protective mechanisms of the organism of the system of combating hyperoxia, the system of combating circulatory hypoxia and the key growth factors of the vascular endothelium during angiogenesis are shown. The pathogenesis of retinopathy of prematurity is described and the first phase of ROP development is analyzed in detail, the reasons for the delay in the maturation of vascular autoregulation are explained. The author proposed to distinguish the first preclinical phase in the ROP classification. In contrast to the modern concentration of attention of ophthalmologists on the active and cicatricial stages, the author proposes to pay special attention to the study of the preclinical stage of ROP, where its pathogenesis is formed.

Intracisternal BioGlue injection in the fetal lamb: a novel model for creation of obstructive congenital hydrocephalus without additional chemically induced neuroinflammation

2019 ◽  
Vol 24 (6) ◽  
pp. 652-662 ◽  
Author(s):  
Marc Oria ◽  
Soner Duru ◽  
Federico Scorletti ◽  
Fernando Vuletin ◽  
Jose L. Encinas ◽  
...  
Keyword(s):  
Calcium Binding ◽  
Repeated Measures ◽  
Obstructive Hydrocephalus ◽  
Critical Threshold ◽  
Control Group ◽  
Chronic Obstructive ◽  
Fetal Sheep ◽  
Cisterna Magna ◽  
Lateral Ventricles ◽  
Fetal Lamb

OBJECTIVEThe authors hypothesized that new agents such as BioGlue would be as efficacious as kaolin in the induction of hydrocephalus in fetal sheep.METHODSThis study was performed in 34 fetal lambs randomly divided into 2 studies. In the first study, fetuses received kaolin, BioGlue (2.0 mL), or Onyx injected into the cisterna magna, or no injection (control group) between E85 and E90. In the second study, fetuses received 2.0-mL or 2.5-mL injections of BioGlue into the cisterna magna between E85 and E90. Fetuses were monitored using ultrasound to assess lateral ventricle size and progression of hydrocephalus. The fetuses were delivered (E120–E125) and euthanized for histological analysis. Selected brain sections were stained for ionized calcium binding adaptor 1 (Iba1) and glial fibrillary acidic protein (GFAP) to assess the presence and activation of microglia and astroglia, respectively. Statistical comparisons were performed with Student’s t-test for 2 determinations and ANOVA 1-way and 2-way repeated measures for multiple determinations.RESULTSAt 30 days after injection, the lateral ventricles were larger in all 3 groups that had undergone injection than in controls (mean diameter in controls 3.76 ± 0.05 mm, n = 5). However, dilatation was greater in the fetuses injected with 2 mL of BioGlue (11.34 ± 4.76 mm, n = 11) than in those injected with kaolin (6.4 ± 0.98 mm, n = 7) or Onyx (5.7 ± 0.31 mm, n = 6) (ANOVA, *p ≤ 0.0001). Fetuses injected with 2.0 mL or 2.5 mL of BioGlue showed the same ventricle dilatation but it appeared earlier (at 10 days postinjection) in those injected with 2.5 mL. The critical threshold of ventricle dilatation was 0.1 for all the groups, and only the BioGlue 2.0 mL and BioGlue 2.5 mL groups exceeded this critical value (at 30 days and 18 days after injection, respectively) (ANOVA, *p ≤ 0.0001). Moderate to severe hydrocephalus with corpus callosum disruption was observed in all experimental groups. All experimental groups showed ventriculomegaly with significant microgliosis and astrogliosis in the subventricular zone around the lateral ventricles. Only kaolin resulted in significant microgliosis in the fourth ventricle area (ANOVA, *p ≤ 0.005).CONCLUSIONSThe results of these studies demonstrate that BioGlue is more effective than Onyx or kaolin for inducing hydrocephalus in the fetal lamb and results in a volume-related response by obstructive space-occupancy without local neuroinflammatory reaction. This novel use of BioGlue generates a model with potential for new insights into hydrocephalus pathology and the development of therapeutics in obstructive hydrocephalus. In addition, this model allows for the study of acute and chronic obstructive hydrocephalus by using different BioGlue volumes for intracisternal injection.

Isolation of a Calcium-binding Peptide from Chlorella Protein Hydrolysates

2010 ◽  
Vol 15 (4) ◽  
pp. 282-286 ◽  
Author(s):  
So-Jeong Jeon ◽  
Ji-Hye Lee ◽  
Kyung-Bin Song
Keyword(s):  
Calcium Binding ◽  
Protein Hydrolysates ◽  
Binding Peptide

Obtaining Site-Specific Calcium-Binding Affinities Of Calmodulin

2003 ◽  
Vol 10 (4) ◽  
pp. 331-345 ◽  
Author(s):  
Jenny Yang ◽  
Amy Gawthrop ◽  
Yiming Ye
Keyword(s):  
Calcium Binding ◽  
Binding Affinities ◽  
Site Specific

How Important are S100A8/S100A9 Calcium Binding Proteins for the Activation of Phagocyte NADPH Oxidase, Nox2

2009 ◽  
Vol 8 (4) ◽  
pp. 282-289 ◽  
Author(s):  
Sylvie Berthier ◽  
Athan Baillet ◽  
Marie-Helene Paclet ◽  
Philippe Gaudin ◽  
Francoise Morel
Keyword(s):  
Nadph Oxidase ◽  
Calcium Binding ◽  
Binding Proteins ◽  
Calcium Binding Proteins ◽  
Phagocyte Nadph Oxidase
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