scholarly journals In vivo changes in carbonic anhydrase activity and histopathology of gill and liver tissues after acute exposure to chlorpyrifos in rainbow trout

2014 ◽  
Vol 65 (4) ◽  
pp. 377-385 ◽  
Author(s):  
Ahmet Topal ◽  
Muhammed Atamanalp ◽  
Ertan Oruç ◽  
Yeliz Demir ◽  
Şükrü Beydemir ◽  
...  

Abstract Chlorpyrifos is an organophosphate pesticide widely used in agriculture and aquaculture. This study investigated its effects on carbonic anhydrase (CA) enzyme activity and histopathology of rainbow trout gill and liver. The fish were exposed to 2.25 (25 % of 96 h LC50), 4.5 (50 % of 96 h LC50), and 6.75 μg L-1 (75 % of 96 h LC50) of chlorpyrifos for 24, 48, 72, and 96 h. CA activity was measured in liver and gills and histopathological changes were examined by light microscopy. The most common liver changes at most of the chlorpyrifos concentrations were hyperaemia and degenerative changes. Gill tissues were characterised by lamellar hyperaemia, lamellar oedemas, clumping, cellular degeneration, hyperplasia, and lamellar atrophy. CA enzyme activity in the gills decreased at all concentrations at 48, 72, and 96 h after exposure to chlorpyrifos (p<0.05). Similarly, there was a time-dependent decrease in CA activity at all of the concentrations in liver tissues (p<0.05). The present study indicated that chlorpyrifos inhibits CA enzyme activity and causes histopathological damage in gill and liver tissues

2004 ◽  
Vol 52 (4) ◽  
pp. 413-422 ◽  
Author(s):  
Ş. Aras-Hisar ◽  
O. Hisar ◽  
Ş. Beydemir ◽  
I. Gülçin ◽  
T. Yanik

Considering that the excessive usage of vitamin E causes hypervitaminosis and thus reduces blood erythrocyte concentrations, therefore it is worth studying how its pharmacological dosage affects the activity of carbonic anhydrase (CA) enzyme found in erythrocytes of rainbow trout (Oncorhynchus mykiss) in vitro and in vivo. Vitamin E inhibited CA enzyme and the IC50 value of the vitamin was 0.039 mM in vitro. Similarly, it was seen that vitamin E inhibited CA enzyme activity after the first hour following vitamin E injections in vivo. The activities of CA in groups of trout given vitamin E injection were measured at 1, 3 and 5 h and the corresponding activities were found to be 772.7 ± 290.5 (P < 0.05), 1286.4 ± 378.2 and 1005.7 ± 436.1 enzyme units (EU) g Hb-1. The difference over the control was significant (P < 0.05) in the first hour and insignificant at 3 and 5 h (P ? 0.05). The activity of CA in the control, which did not contain vitamin E, was determined as 1597.7 ± 429.0 EU g Hb-1.


1981 ◽  
Vol 29 (10) ◽  
pp. 1213-1218 ◽  
Author(s):  
C M Schreiner ◽  
K S Hirsch ◽  
W J Scott

The carbonic anhydrase inhibitor, acetazolamide, leads to a unique distal postaxial right forelimb deformity in rats and CBA/J mice, but SWV mice are completely resistant. Using Hansson's histochemical method, the distribution of carbonic anhydrase and its inhibition by acetazolamide in rat, CBA/J mouse, and SWV mouse embryos were compared. Carbonic anhydrase activity was demonstrable in many tissues of sensitive rat and CBA/J mouse embryos and in resistant SWV mouse embryos. The forelimb buds of resistant and sensitive embryos possess carbonic anhydrase activity in the area between the ectoderm and adjacent mesenchyma with no localization of enzyme activity corresponding to the malformation seen in acetazolamide teratogenesis. This suggests that carbonic anhydrase in the forelimbs is not the primary site of action for acetazolamide. A distinctive staining pattern of nucleated erythrocytes in resistant embryos indicated the presence of a low activity form of carbonic anhydrase in nearly half of the erythrocytes. A five-to tenfold greater amount of acetazolamide was needed to completely inhibit carbonic anhydrase activity in nucleated erythrocytes from resistant embryos than in those from sensitive embryos. The existence of a low activity form of carbonic anhydrase in SWV embryo erythrocytes may be the basis of resistance to acetazolamide teratogenesis.


2015 ◽  
Vol 59 (8) ◽  
pp. 4436-4445 ◽  
Author(s):  
Benjamin K. Johnson ◽  
Christopher J. Colvin ◽  
David B. Needle ◽  
Felix Mba Medie ◽  
Patricia A. DiGiuseppe Champion ◽  
...  

ABSTRACTMycobacterium tuberculosismust sense and adapt to host environmental cues to establish and maintain an infection. The two-component regulatory system PhoPR plays a central role in sensing and responding to acidic pH within the macrophage and is required forM. tuberculosisintracellular replication and growthin vivo. Therefore, the isolation of compounds that inhibit PhoPR-dependent adaptation may identify new antivirulence therapies to treat tuberculosis. Here, we report that the carbonic anhydrase inhibitor ethoxzolamide inhibits the PhoPR regulon and reduces pathogen virulence. We show that treatment ofM. tuberculosiswith ethoxzolamide recapitulatesphoPRmutant phenotypes, including downregulation of the core PhoPR regulon, altered accumulation of virulence-associated lipids, and inhibition of Esx-1 protein secretion. Quantitative single-cell imaging of a PhoPR-dependent fluorescent reporter strain demonstrates that ethoxzolamide inhibits PhoPR-regulated genes in infected macrophages and mouse lungs. Moreover, ethoxzolamide reducesM. tuberculosisgrowth in both macrophages and infected mice. Ethoxzolamide inhibitsM. tuberculosiscarbonic anhydrase activity, supporting a previously unrecognized link between carbonic anhydrase activity and PhoPR signaling. We propose that ethoxzolamide may be pursued as a new class of antivirulence therapy that functions by modulating expression of the PhoPR regulon and Esx-1-dependent virulence.


1986 ◽  
Vol 60 (2) ◽  
pp. 638-645 ◽  
Author(s):  
R. P. Henry ◽  
S. J. Dodgson ◽  
R. E. Forster ◽  
B. T. Storey

sCarbonic anhydrase activity in rat lungs perfused free of blood was localized by homogenization of the tissue followed by differential centrifugation. Four fractions were obtained from the homogenate, a cell debris pellet with a mitochondrial pellet and a microsomal pellet with a clear cytosol supernatant. The last named fraction contained 67% of the total enzyme activity; the cell debris contained 18%, and the mitochondrial and microsomal contained 8 and 7%, respectively. Of the 33% of enzyme activity associated with the pellet fraction, 25% could be experimentally defined as membrane associated by its solubilization with 0.3 M tris-(hydroxymethyl) aminoethane sulfate buffer. The remainder was defined as membrane bound. Purification of the soluble carbonic anhydrase from the lung yielded two isozymes with electrophoretic and inhibitor sensitivities apparently identical with the blood isozymes. Hemoglobin analysis showed that the lung isozymes could not have included more than 0.03% enzyme from blood contamination. The carbonic anhydrase activity present in the whole rat lung would give an average acceleration of the CO2 hydration reaction under physiological conditions over the uncatalyzed rate of 122, sufficient to maintain equilibration between CO2 and plasma HCO3- during blood transit of the lung. If the membrane-associated activity is mostly on the plasma membrane of the endothelial cells and available to the capillary blood, it would be sufficient to give this acceleration. We suggest that the possible source of this membrane-associated activity might be adsorption from the blood of carbonic anhydrase liberated by erythrocyte lysis.


1972 ◽  
Vol 20 (5) ◽  
pp. 319-330 ◽  
Author(s):  
THOMAS F. MUTHER

The histochemical methods for carbonic anhydrase are not based on the postulated dehydration of HCO3–. The staining is caused by the formation of an unknown reactive Co compound in the surface layer secondary to enzyme-independent alkalinization of the medium. Kinetic analysis of the reaction shows that loss of CO2 from the medium is rate-limiting. Carbonic anhydrase inhibitors delay the staining by interacting with Co and not by inhibiting the enzyme; they are effective when used after the reaction is complete. The reaction can also be inhibited by agents which are not carbonic anhydrase inhibitors, such as sodium lauryl sulfate and 5-aminothiadiazole, but not by in vivo administered acetazolamide. A comparison of the effect of various fixatives on the biochemical and histochemical enzyme activity shows no correlation. While carbonic anhydrase itself is stained by the reaction, the methods lack the claimed specificity for it.


2016 ◽  
Vol 7 (3) ◽  
pp. 23-27 ◽  
Author(s):  
Abhijit Bhakta ◽  
Maitreyi Bandyopadhyay ◽  
Sayantan Dasgupta ◽  
Santanu Sen ◽  
Arun Kumar ◽  
...  

Background: In contrast to its role as poison, hydrogen sulfide (H2S) is recently considered as a gaso-transmitter which mediates important physiologic functions in humans. Evidence is accumulating to demonstrate that inhibitors of H2S production or therapeutic H2S donor compounds exert significant effects in various experimental models. Carbonic anhydrases (CA) are a group of zinc-containing metalloenzymes that catalyse the reversible hydration of carbon dioxide. CAs activity in erythrocytes (CAI and CAII) has recently been observed to be associated with various pathological conditions especially in diabetes mellitus, hypertension and lipid disorders. Alteration of this enzyme activity has been reported by the effect of advanced glycation end products methylglyoxal and reduced glutathione.   Aims and Objectives: As H2S, being a mediator of many physiological functions and synthesized in vivo, may affect functions of many intracellular proteins like carbonic anhydrase, the objective of this study is to find out if there is any change in the carbonic anhydrase activity under the effect of H2S- donor NaHS in dose dependant manner using RBC model in vitro.Materials and Methods: Blood sample was collected from forty (40) numbers of healthy volunteers of 18-40 years of in heparin containing vials and packed cells were prepared immediately by centrifugation  The packed erythrocytes were washed three times with normal saline and  diluted (1:10) with the normal saline. One ml each of diluted packed cells was taken in eight test tubes. Serial dilutions of NaHS (1to 250 µMol/L) was added to all the test tubes except for the first test tube where only normal saline was added and   incubated at room temperature for one hour. Haemolysates was prepared from the erythrocytes with equal volume of distilled water in each tube and the CA activity was determined in the haemolysates using standardized method.Results: There is significant increase of CA activity in dose dependent manner under the effect of NaHS and also compared to the activity of hemolysate prepared without NaHS.  Conclusions:Our study for the first time demonstrated that the Carbonic Anhydrase activity of erythrocytes is significantly increases by the effect of NaHS and this study reveals some important biological role of H2S and carbonic anhydrase.Asian Journal of Medical Sciences Vol. 7(3) 2016 23-27


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