An evaluation of several potential factors limiting carbon dioxide excretion by rainbow trout (Oncorhynchus mykiss) red blood cells was performed in vitro using a recently developed radioisotopic assay. Red blood cell (RBC) CO2 excretion was reduced by pretreatment (30min) of blood with the carbonic anhydrase inhibitor acetazolamide (final nominal concentration 1024 mol l21) or the Cl/HCO3 exch...

OBJECTIVES To determine the serum levels of methylglyoxal (MG) and carbonic anhydrase (CA) activity in known cases of type-II diabetes mellitus with insulin resistance and to compare them with age-sex matched healthy controls. METHODS Eightysix participants were enrolled for the present case-controlled study with ages ranging from 25 to 44 years. The analytes measured were fasting blood gluco...

Carbamoyl phosphate has been shown to inhibit carbonic anhydrase (CA) isozymes CA I, CA II and CA III. This physiologically important molecule is the most potent, naturally occurring inhibitor of carbonic anhydrase yet found. It is also unique, among carbonic anhydrase inhibitors discovered hitherto, in that it inhibits the 3 isozymes with equal effect, despite their strikingly different proper...

Carbonic anhydrase activity was characterized in freshly dissociated Müller cells of the salamander retina. Intracellular pH was monitored using ratio imaging of the indicator dye BCECF as extracellular PCO2 was varied. The extracellular solution was switched rapidly (141 ms rise time) from a HEPES buffered to a CO2-HCO3- buffered solution (both pH 7.4). Introduction of CO2-HCO3- produced a rap...

A physiologically significant level of intracellular carbonic anhydrase has been identified in Chlamydomonas reinhardtii after lysis of the cell wall-less mutant, cw15, and two intracellular polypeptides have been identified which bind to anti-carbonic anhydrase antisera. The susceptibility of the intracellular activity to sulfonamide carbonic anhydrase inhibitors is more than three orders-of-m...

Keywords: 5-amino-1,3,4-thiadiazole-2-thiol derivatives, diuretic activity, saluretic/natriuretic/carbonic anhydrase inhibition indexes, SAR,

We investigated the activity of carbonic anhydrase in blood-free perfused white skeletal muscles of the rabbit. Carbonic anhydrase activities were measured in supernatants and in Triton extracts of the particulate fractions of white-skeletal-muscle homogenate by using a rapid-reaction stopped-flow apparatus equipped with a pH electrode. An average carbonic anhydrase concentration of about 0.5 m...

The effect of calcitonin (CT) and parathyroid hormone (PTH) on carbonic anhydrase (carbonate hydrolyase, EC 4.2.1.1.) activity was tested in human erythrocyte hemolysates and with purified carbonic anhydrases I and II. The most important effect was on carbonic anhydrase II: CT showed a 2-fold increase and PTH showed a 50% decrease of carbonic anhydrase activity. This effect was observed at low ...

A physiologically significant level of intracellular carbonic anhydrase has been idenfified in Chlamydomonas reinhardtii after lysis of the cell wall-less mutant, cw15, and two intracellular polypeptides have been identified which bind to anti-carbonic anhydrase antisera. The susceptibility of the intracellular activity to sulfonamide carbonic anhydrase inhibitors is more than three orders-of-m...

Present understanding of gene expression in erythropoietic tissues is derived solely from studies of the globin genes. Of the three distinct carbonic anhydrase (carbonate dehydratase; carbonate hydro-lyase, EC 4.2.1.1) isozymes, carbonic anhydrase I is erythrocyte-specific and, in humans, is under developmental control. The appearance of carbonic anhydrase I in the erythrocyte late in fetal lif...