scholarly journals A Novel Stopped-Flow Assay for Quantitating Carbonic-Anhydrase Activity and Assessing Red-Blood-Cell Hemolysis

2017 ◽  
Vol 8 ◽  
Author(s):  
Pan Zhao ◽  
R. Ryan Geyer ◽  
Walter F. Boron
Keyword(s):  
Carbonic Anhydrase ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Carbonic Anhydrase Activity ◽  
Stopped Flow

scholarly journals Why is there no carbonic anhydrase activity available to fish plasma?

1995 ◽  
Vol 198 (1) ◽  
pp. 31-38 ◽  
Author(s):  
J Lessard ◽  
A Val ◽  
S Aota ◽  
D Randall
Keyword(s):  
Carbonic Anhydrase ◽  
Blood Cell ◽  
Cell Volume ◽  
Red Blood Cell ◽  
Short Circuit ◽  
Hemoglobin Concentration ◽  
Carbonic Anhydrase Activity ◽  
Control Group ◽  
Acid Loading

Carbonic anhydrase (CA) is absent from the plasma of vertebrates. In vitro, CA in fish plasma will short-circuit the effect of catecholamines, which is to increase red blood cell (RBC) pH and volume, both of which enhance the affinity of hemoglobin for O2. CA was infused into trout for a period of 6 h and injected after 48 h, during which the animal was submitted to deep hypoxia (PO2=30­35 mmHg; 4.0­4.7 kPa). O2 content, lactate content, catecholamine levels, hematocrit, hemoglobin concentration and pHi were similar to those in the saline-infused control group. In contrast, cell volume was significantly higher and pHe, total CO2 content and organic phosphate levels were significantly lower than in the control group. The concentration of CA was not high enough completely to short-circuit the increase in pHi and red blood cell volume caused by catecholamines. The lower pHe in the CA-infused animals could enhance the activity of the Na+/H+ pump, which would keep the nucleotide triphosphate levels low. pH is a balance between acid loading at the muscle and acid excretion at the gills or the kidneys; we cannot distinguish between which of these resulted in a decrease of plasma pH. In conclusion, CA in plasma did not cause the expected reduction in blood oxygen content but did have a marked effect on plasma total CO2 content.

scholarly journals Changes in the red blood cell enzyme, carbonic anhydrase, following blood transfusion.

1981 ◽  
Vol 27 (6) ◽  
pp. 541-545
Author(s):  
Kenji Taki ◽  
Koji Murakami ◽  
Takae Kawamura ◽  
Mieko Takamura ◽  
Reiji Wakusawa
Keyword(s):  
Blood Transfusion ◽  
Carbonic Anhydrase ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Cell Enzyme

Postcapillary changes in blood pH in vivo during carbonic anhydrase inhibition

1977 ◽  
Vol 43 (4) ◽  
pp. 582-590 ◽  
Author(s):  
E. D. Crandall ◽  
A. Bidani ◽  
R. E. Forster
Keyword(s):  
Carbonic Anhydrase ◽  
Carbonic Anhydrase Activity ◽  
Stopped Flow ◽  
Arterial Blood ◽  
Blood Ph ◽  
Pulmonary Capillary ◽  
Carbonic Anhydrase Inhibition ◽  
Glass Ph Electrode ◽  
Electrode Chamber

A rapidly responding stopped-flow glass pH electrode apparatus was used to investigate pH changes in blood in vivo after it exits from an exchange capillary. Arterial blood was drawn from anesthetized animals through the apparatus. Temperature and pH of the blood in the electrode chamber were continuously recorded, both during withdrawal and after flow was stopped. Blood pH did not change after stopping flow in control experiments. When benzolamide (2 mg/kg) was given to inhibit carbonic anhydrase activity available to plasma (e.g., due to lysis) while having less effect on intracellular activity, pH increased 0.02–0.04 (t1/2 approximately 8 s) after stopping flow. Administration of acetazolamide (50 mg/kg) resulted in pH decreasing 0.07–0.10 (t1/2 approximately 15 s) after stopping flow. Ventilation for 1 min with N2 resulted in an increased rise in pH for the benzolamide-treated animals but a decreased fall in pH for the acetazolamide-treated animals. These shifts in arterial blood pH after gas exchange are largely due to disequilibrium of [H+] between red cells and plasma at the end of the pulmonary capillary.

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