scholarly journals Preventive effect of melatonin against dimethylbenz(a)anthracene-induced changes in renal tubules of Mice: an Autoradiographic Study

2015 ◽  
Vol 1 (3) ◽  
pp. 127-138
Author(s):  
Margit Semmler ◽  
Abdel-Baset Aref
Keyword(s):  
Autoradiographic Study ◽  
Renal Tubules ◽  
Preventive Effect ◽  
Induced Changes

Abstract 196: Involvement of Peroxynitrite Formation in Angiotensin II Induced Changes in Na+K+ATPase Activity in HK2 Cells

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Arpan K Maiti ◽  
Mohammed T Islam ◽  
Ryosuke Satou ◽  
Dewan S Majid
Keyword(s):  
Angiotensin Ii ◽  
Colorimetric Assay ◽  
Renin Angiotensin System ◽  
Human Kidney ◽  
Protective Role ◽  
Renal Tubules ◽  
Proximal Tubule Cell ◽  
Wide Range ◽  
Induced Changes ◽  
Hk2 Cells

Angiotensin II (AngII) induces both superoxide (O 2 - ) and nitric oxide (NO) generation forming peroxynitrite (ONOO - ) in biological systems. To determine the role of ONOO - in AngII induced sodium excretory responses, we examined Na + K + ATPase (NKA) activity in cultured HK2 cells (human kidney proximal tubule cell line) incubated for 30 min with a wide range (10 pM to 200 μM) of AngII concentrations (conc) in the presence or absence of a ONOO - scavenger, mercapto-ethyl-guanadine (MEG; 200μM). Post incubation HK2 cellular membrane fractions were used for measurement of NKA activity via colorimetric assay capable of detecting inorganic phosphate (Pi). Baseline value of NKA activity in these HK2 cells was measured as 10.3 ±0.7 μmoles of Pi liberated/mg protein/hr (n=12). AngII exerts dose-dependent differential effects on NKA activity. Compared to the baseline value, NKA activity was increased at lower conc (13.7±1.3% at 10 pM to 19.6±1.5% at 100nM) and decreased at higher conc (-6.0±0.8% at 1 μM to -38±2.1% at 200 μM ) without any significant effect at 500 nM conc (-1.2±0.6%) of AngII. Interestingly, MEG treatment markedly attenuated these AngII induced changes in NKA activity, both at lower conc (activity increased only to 7.8±0.67% at 10 pM and to 8.9±0.57% at 100nM; an average reduction of 33.2±2.4% in stimulatory effects) and at higher conc (activity decreased to -3.0±0.7% at 1 μM and to -20±0.57% at 200 μM; an average reduction of 54.4±4.1% in inhibitory effects). Co-incubation with O 2 - scavenger, tempol (1 mM) or NO synthase inhibitor, nitro-L-arginine methyl ester (100 μM) did not alter these AngII induced responses in HK2 cells indicating that neither O 2 - , nor NO, was directly involved in mediating these responses. AT 1 receptor (AT 1 R) blocker, losartan (10μM) treatment prevented these AngII induced changes on NKA activity confirming the involvement of AT 1 R signaling in these responses. These findings demonstrate a direct contributory role for concomitant ONOO - generation in mediating AngII induced changes in NKA activity in the proximal tubular cells. These data also suggest a reno-protective role for ONOO - in minimizing sodium retaining action of AngII by the renal tubules, particularly in the conditions associated with enhanced renin-angiotensin system.

scholarly journals Assessment of the Protective Effect of Lepidium sativum against Aluminum-Induced Liver and Kidney Effects in Albino Rat

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Maha Jameal Balgoon
Keyword(s):  
Structural Changes ◽  
Lepidium Sativum ◽  
Albino Rats ◽  
Renal Tubules ◽  
Albino Rat ◽  
Antioxidant Power ◽  
Superior Effect ◽  
Ferric Reducing Antioxidant Power ◽  
Liver And Kidney ◽  
Induced Changes

Background and Objectives. Environmental pollution with the different Aluminum (Al) containing compounds has been increased. Liver and kidney are two vital organs targeted by Al accumulation. The aim of this study was to assess the possible protective and curative effects of Lepidium sativum Linn (LS) against Al-induced impairment of liver and kidney in albino rat and to explore the mechanism behind this effect. Materials and Methods. This experimental animal-based study included fifty albino rats divided into five groups, the control, LS-treated (20 mg/kg), AlCl3-treated (10 mg/kg), AlCl3 then LS, and AlCl3 plus LS-treated, simultaneously for 8 weeks. At the end of the experiment, hepatic and renal functions as well as the biomarkers of antioxidants activities were assessed in the serum. Both liver and kidney were dissected out and histopathologically examined. Results. This study showed that administration of AlCl3 caused a significant (p<0.05) reduction in rats body weight. It significantly increased serum AST, ALT, ALP, bilirubin, urea, and creatinine levels and decreased total protein and albumin. AlCl3 significantly reduced enzymatic (catalase), nonenzymatic (reduced glutathione), and ferric reducing antioxidant power (FRAP) in the serum. Histopathologically, it induced necrosis and degeneration of hepatocytes, glomeruli, and renal tubules. Administration of LS after or along with AlCl3 significantly restored the serum biomarkers of liver and kidney functions to their near-normal levels and had the ability to overcome Al-induced oxidative stress and preserved, to some extent, the normal hepatic and renal structure. The coadministration of LS had a superior effect in alleviating Al-induced changes. Conclusion. Exposure to AlCl3 induced a set of functional and structural changes in the liver and kidney of rats evident through both biochemical and histopathological assessment. The antioxidant activity of LS seeds mediated a protective and curative effect of LS against such changes. Further study through a rigorous clinical trial to prove LS activity on human is recommended.

Phospholipase A-induced changes in AMPA receptor: An autoradiographic study

Neuroreport ◽  
1992 ◽  
Vol 3 (6) ◽  
pp. 315-518 ◽  
Author(s):  
Georges Tocco ◽  
Guy Massicotte ◽  
Steve Standley ◽  
Richard F. Thompson ◽  
Michel Baudry
Keyword(s):  
Ampa Receptor ◽  
Autoradiographic Study ◽  
Phospholipase A ◽  
Induced Changes

PPAR-γ-independent inhibitory effect of rosiglitazone on glucose synthesis in primary cultured rabbit kidney-cortex tubules

2008 ◽  
Vol 86 (5) ◽  
pp. 396-404 ◽  
Author(s):  
Rafal A. Derlacz ◽  
Karol Hyc ◽  
Michal Usarek ◽  
Adam K. Jagielski ◽  
Jakub Drozak ◽  
...  
Keyword(s):  
Phosphoenolpyruvate Carboxykinase ◽  
Cultured Cells ◽  
Rabbit Kidney ◽  
Kidney Cortex ◽  
Renal Tubules ◽  
Drug Induced ◽  
Ppar Γ ◽  
Liver And Kidney ◽  
Glucose Synthesis ◽  
Induced Changes

Therapeutic effect of rosiglitazone has been reported to result from an improvement of insulin sensitivity and inhibition of glucose synthesis. As the latter process occurs in both liver and kidney cortex the aim of this study was to elucidate the rosiglitazone action on glucose formation in both tissues. Primary cultured cells of both liver and kidney cortex grown in defined medium were use throughout. To identify the mechanism responsible for drug-induced changes, intracellular gluconeogenic intermediates and enzyme activities were determined. In contrast to hepatocytes, the administration of a 10 µmol/L concentration of rosiglitazone to renal tubules resulted in about a 70% decrease in the rate of gluconeogenesis, accompanied by an ~75% decrease in alanine utilization and a 35% increase in lactate synthesis. The effect of rosiglitazone was not abolished by GW9662, the PPAR-γ irreversible antagonist, indicating that this action is not dependent on PPAR-γ activation. In view of rosiglitazone-induced changes in gluconeogenic intermediates and a diminished incorporation of 14CO2 into pyruvate, it is likely that the drug causes a decline in flux through pyruvate carboxylase and (or) phosphoenolpyruvate carboxykinase. It is likely that the hypoglycemic action of rosiglitazone is PPAR-γ independent and results mainly from its inhibitory effects on renal gluconeogenesis.

Interpretation of irradiation-induced changes in electron diffractograms and images of extinction contours at low temperatures

1984 ◽  
Vol 42 ◽  
pp. 268-269
Author(s):  
E. Knapek ◽  
H. Formanek ◽  
G. Lefranc ◽  
I. Dietrich
Keyword(s):  
Low Temperatures ◽  
Carbon Films ◽  
Organic Crystals ◽  
Wide Spread ◽  
Lens System ◽  
Preparation Conditions ◽  
Thin Carbon ◽  
Electron Diffractograms ◽  
Diffraction Patterns ◽  
Induced Changes

A few years ago results on cryoprotection of L-valine were reported, where the values of the critical fluence De i.e, the electron exposure which decreases the intensity of the diffraction reflections by a factor e, amounted to the order of 2000 + 1000 e/nm2. In the meantime a discrepancy arose, since several groups published De values between 100 e/nm2 and 1200 e/nm2 /1 - 4/. This disagreement and particularly the wide spread of the results induced us to investigate more thoroughly the behaviour of organic crystals at very low temperatures during electron irradiation.For this purpose large L-valine crystals with homogenuous thickness were deposited on holey carbon films, thin carbon films or Au-coated holey carbon films. These specimens were cooled down to nearly liquid helium temperature in an electron microscope with a superconducting lens system and irradiated with 200 keU-electrons. The progress of radiation damage under different preparation conditions has been observed with series of electron diffraction patterns and direct images of extinction contours.

Drug Induced Changes in Cell Organelles

1968 ◽  
Vol 26 ◽  
pp. 110-111
Author(s):  
Sarah A. Luse
Keyword(s):  
Clinical Medicine ◽  
Cell Organelles ◽  
Riboflavin Deficiency ◽  
Drug Induced ◽  
New Era ◽  
Health And Disease ◽  
In The Beginning ◽  
Cellular Pathology ◽  
Induced Changes ◽  
The Impact

In the mid-nineteenth century Virchow revolutionized pathology by introduction of the concept of “cellular pathology”. Today, a century later, this term has increasing significance in health and disease. We now are in the beginning of a new era in pathology, one which might well be termed “organelle pathology” or “subcellular pathology”. The impact of lysosomal diseases on clinical medicine exemplifies this role of pathology of organelles in elucidation of disease today.Another aspect of cell organelles of prime importance is their pathologic alteration by drugs, toxins, hormones and malnutrition. The sensitivity of cell organelles to minute alterations in their environment offers an accurate evaluation of the site of action of drugs in the study of both function and toxicity. Examples of mitochondrial lesions include the effect of DDD on the adrenal cortex, riboflavin deficiency on liver cells, elevated blood ammonia on the neuron and some 8-aminoquinolines on myocardium.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

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.

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