scholarly journals Effects of nicotine and Vitamin E on Carbonic anhydrase activity in some rat tissues In Vivo and In Vitro

2005 ◽  
Vol 20 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Mehmet Çiftçi ◽  
Metin Bülbül ◽  
Mustafa Gül ◽  
Kenan Gümüs¸tekin ◽  
S¸enol Dane ◽  
...  
Keyword(s):  
Vitamin E ◽  
Carbonic Anhydrase ◽  
Carbonic Anhydrase Activity ◽  
Rat Tissues

Effects of red blood cell HCO3(-)/Cl- exchange kinetics on lung CO2 transfer: theory

1981 ◽  
Vol 50 (2) ◽  
pp. 265-271 ◽  
Author(s):  
E. D. Crandall ◽  
A. Bidani
Keyword(s):  
Carbonic Anhydrase ◽  
Carbonic Anhydrase Activity ◽  
Major Influence ◽  
Gas Transfer ◽  
Red Cell ◽  
Dehydration Reactions ◽  
Lung Capillaries ◽  
Co2 Elimination

A mathematical model has been used to study the influences of the kinetics of erythrocyte HCO3(-)/Cl-- exchange on CO2 elimination in the lung. In addition to the chloride shift, the model includes 1) CO2-H2CO3 hydration-dehydration reactions in plasma and erythrocytes; 2) CO2 reactions with hemoglobin; 3) O2 binding to hemoglobin; 4)buffering of H+ intra- and extracellularly; 5) red cell volume changes; and 6) diffusion of gases between alveoli and blood. Carbonic anhydrase activity was assumed to be available to plasma as it passes through the lung capillaries. The results show that a reduction of PHCO3(-) leads to a reduction in pulmonary CO2 elimination of up to 30%, whether or not carbonic anhydrase activity is available to plasma. Characteristic slow downstream pH and PCO2 changes predicted for each case may represent an explanation for the apparent discrepancy between in vivo and in vitro slow downstream pH changes reported previously. We conclude that red cell HCO3(-)/Cl- exchange partially limits CO2 elimination from blood in the lung and may have a major influence on capillary gas transfer when its speed is abnormally slow.

Effect of vitamin E on carbonic anhydrase enzyme activity in rainbow trout (Oncorhynchus mykiss) erythrocytes in vitro and in vivo

2004 ◽  
Vol 52 (4) ◽  
pp. 413-422 ◽  
Author(s):  
Ş. Aras-Hisar ◽  
O. Hisar ◽  
Ş. Beydemir ◽  
I. Gülçin ◽  
T. Yanik
Keyword(s):  
Enzyme Activity ◽  
Rainbow Trout ◽  
Vitamin E ◽  
Carbonic Anhydrase ◽  
Oncorhynchus Mykiss ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Blood Erythrocyte ◽  
The Difference

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.

scholarly journals Nuclear carbonic anhydrase 6B associates with PRMT5 to epigenetically promote IL-12 expression in innate response

2017 ◽  
Vol 114 (32) ◽  
pp. 8620-8625 ◽  
Author(s):  
Jia Xu ◽  
Xiaoqing Xu ◽  
Bingjing Wang ◽  
Yuanwu Ma ◽  
Lianfeng Zhang ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Protective Immunity ◽  
Histone H3 ◽  
Carbonic Anhydrase Activity ◽  
Chromatin Accessibility ◽  
Interleukin 12 ◽  
Innate Response ◽  
Efficient Induction

Interleukin-12 (IL-12) is critical for induction of protective immunity against intracellular bacterial infection. However, the mechanisms for efficient induction of IL-12 in innate response remain poorly understood. Here we report that the B type of carbonic anhydrase 6 (Car6-b, which encoded CA-VI B) is essential for host defense against Listeria monocytogenes (LM) infection by epigenetically promoting IL-12 expression independent of its carbonic anhydrase activity. Deficiency of Car6-b attenuated IL-12 production upon LM infection both in vitro and in vivo. Car6−/− mice were more susceptible to LM infection with less production of IL-12. Mechanistically, the nuclear localized CA-VI B selectively promotes IL-12 expression by interaction with protein arginine N-methyltransferase 5 (PRMT5), which reduces symmetric dimethylation of histone H3 arginine 8 modification (H3R8me2s) at Il12 promoters to facilitate chromatin accessibility, selectively enhancing c-Rel binding to the Il12b promoter. Our findings add insights to the epigenetic regulation of IL-12 induction in innate immunity.

scholarly journals Effects of nicotine and vitamin E on 6-phosphogluconate dehydrogenase activity in some rat tissues in vivo and in vitro

2008 ◽  
Vol 23 (2) ◽  
pp. 261-265
Author(s):  
Mehmet Ciftci ◽  
Hayrullah Yilmaz ◽  
T. Abdulkadir Coban ◽  
Mustafa Gul ◽  
Kenan Gumustekin ◽  
...  
Keyword(s):  
Vitamin E ◽  
Dehydrogenase Activity ◽  
Rat Tissues ◽  
Phosphogluconate Dehydrogenase

scholarly journals Protective effects of carbonic anhydrase inhibition in brain ischaemia in vitro and in vivo models

2021 ◽  
Vol 36 (1) ◽  
pp. 964-976
Author(s):  
Ilaria Dettori ◽  
Irene Fusco ◽  
Irene Bulli ◽  
Lisa Gaviano ◽  
Elisabetta Coppi ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Protective Effects ◽  
Brain Ischaemia ◽  
In Vivo Models ◽  
Carbonic Anhydrase Inhibition

THE BINDING OF [1,2-3H]TESTOSTERONE WITHIN NUCLEI OF THE RAT PROSTATE

1969 ◽  
Vol 44 (3) ◽  
pp. 323-333 ◽  
Author(s):  
W. I. P. MAINWARING
Keyword(s):  
Molecular Weight ◽  
Equilibrium Dialysis ◽  
Prostate Gland ◽  
Ventral Prostate ◽  
Rat Tissues ◽  
Receptor Complex ◽  
Rat Prostate ◽  
Binding Component

SUMMARY The specificity of the binding of [1,2-3H]testosterone to nuclei of various rat tissues in vivo has been studied. A significant amount of radioactivity was retained in the nuclei of androgen-dependent tissues only, particularly the ventral prostate gland. The bound radioactivity was only partially recovered as [1,2-3H]testosterone; the remainder was identified as [3H]5α-dihydrotestosterone. Efforts were made to characterize the binding component, or 'receptor', in prostatic nuclei. On digestion of nuclei labelled in vivo with [1,2-3H]testosterone, with enzymes of narrow substrate specificity, only trypsin released tritium, suggesting that the receptor is a protein. On the basis of subfractionation studies of labelled nuclei, the receptor is an acidic protein. The androgen—receptor complex could be effectively extracted from the prostatic nuclei in 1 m-NaCl and from the results of fractionations on a calibrated agarose column, the complex has a molecular weight 100,000–120,000. The specificity of the binding of steroids to such 1 m-NaCl extracts in vitro was investigated by the equilibrium dialysis procedure. Under these conditions, the specificity of the binding of [1,2-3H]testosterone demonstrated in vivo could not be simulated. The receptor is probably part of the chromatin complex but its precise intranuclear localization cannot be determined by biochemical procedures alone.

scholarly journals Crystal structure of human carbonic anhydrase II at 1.95 Å resolution in complex with 667-coumate, a novel anti-cancer agent

2005 ◽  
Vol 385 (3) ◽  
pp. 715-720 ◽  
Author(s):  
Matthew D. LLOYD ◽  
Richard L. PEDERICK ◽  
Ramanathan NATESH ◽  
L. W. Lawrence WOO ◽  
Atul PUROHIT ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Phase 1 ◽  
Structural Basis ◽  
Pharmacokinetic Studies ◽  
Reversible Binding ◽  
X Ray Crystallography ◽  
Hydrophobic Binding ◽  
Cancer Agent

CA (carbonic anhydrase) catalyses the reversible hydration of carbon dioxide into bicarbonate, and at least 14 isoforms have been identified in vertebrates. The role of CA type II in maintaining the fluid and pH balance has made it an attractive drug target for the treatment of glaucoma and cancer. 667-Coumate is a potent inhibitor of the novel oncology target steroid sulphatase and is currently in Phase 1 clinical trials for hormone-dependent breast cancer. It also inhibits CA II in vitro. In the present study, CA II was crystallized with 667-coumate and the structure was determined by X-ray crystallography at 1.95 Å (1 Å=0.1 nm) resolution. The structure reported here is the first for an inhibitor based on a coumarin ring and shows ligation of the sulphamate group to the active-site zinc at 2.15 Å through a nitrogen anion. The first two rings of the coumarin moiety are bound within the hydrophobic binding site of CA II. Important residues contributing to binding include Val-121, Phe-131, Val-135, Leu-141, Leu-198 and Pro-202. The third seven-membered ring is more mobile and is located in the channel leading to the surface of the enzyme. Pharmacokinetic studies show enhanced stability of 667-coumate in vivo and this has been ascribed to binding of CA II in erythrocytes. This result provides a structural basis for the stabilization and long half-life of 667-coumate in blood compared with its rapid disappearance in plasma, and suggests that reversible binding of inhibitors to CA may be a general method of delivering this type of labile drug.

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