Carbonic anhydrase occurrence

If a carbonic anhydrase inhibitor is being given for absence or nonlocalized epileptic seizures, the nurse assesses the patient at frequent intervals for the occurrence of seizures, especially early in therapy and in patients known to experience seizures at frequent intervals. If a seizure does occur, the nurse records a description of the seizure in the patient s chart, including time of onset and duration. Accurate descriptions of the pattern and the number of seizures occurring each day helps the primary health care provider plan future therapy and adjust drug dosages as needed. 

However, in the study of these compounds, other applications were acquired. The occurrence of carbonic anhydrase, as a functionally important enzyme in the eye and in the central nervous system, led to the use of the inhibitors to treat glaucoma and epilepsy. Methazolamide has certain advantages due to greater penetration and intracellular distribution (17) its principal use is in the treatment of glaucoma. 

Is it possible to speed up a reaction without changing the temperature or the reactant concentrations Yes, by using something called a catalyst, a substance that speeds up a reaction without being consumed. This may sound too good to be tme, but it is a very common occurrence. In fact, you would not be alive now if your body did not contain thousands of catalysts called enzymes. Enzymes allow our bodies to speed up complicated reactions that would be too slow to sustain life at normal body temperatures. For example, the enzyme carbonic anhydrase speeds up the reaction between carbon dioxide and water... 

Functional differences, such as variations in the occurrence of certain enzymes, may exist between different vascular beds. In brain capillary endothelial cells, the distribution of alkaline phosphatase and Na , K ATPase differs between the luminal and antiluminal cytoplasmic membranes. Cadmium is known to inhibit several SH-containing enzymes and it might be speculated that the content and subcellular distribution of enzymes in ganglionic endothelial cells are of importance for the preferential occurrence of cadmium-induced vascular injury in ganglia. A similar theory has been proposed to explain the vascular damage caused by cadmium in the testis. Thus, Aoki and Hoffer suggested that a cadmium-sensitive testicular isoenzyme of carbonic anhydrase may in some way be associated with the capillary endothelial cells. 

The cis-conformation of the peptide bond has been observed in globular proteins for a small number of proline residues. It was reported to occur in ribonuclease (Wyckoff et al, 1970), erythrocruorin (Huber et al., 1971), subtilisin (Alden et al., 1973), thermolysin (Matthews et al, 1974), the Bence-Jones dimer REI (Huber and Steigemann, 1974), and carbonic anhydrase (Kannan et al, 1975). One nonproline cis conformation was reported for carboxypeptidase involving the bond between Ser 197 and Tyr 198 (Hartsuck and Lipscomb, 1971). The rare occurrence of cis peptide units is only partially explained by the intrinsic energy of the cis over the trans conformation which is small in proteins (Zimmerman and Scheraga, 1976 see also Section 2.3.2). As reported by Ramanchandran and Mitra (1976), an additional factor is the conformational restriction imposed by the occurrence of a cis peptide unit in a chain of trans units. 

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