The Effect of Acetazolamide upon Tissue Concentrations of Bicarbonate, Lactate, and Pyruvate in the Rat Brain

• Published in: Acta Physiologica Scandinavica
• Main Authors: Kjällquist, A., Nardini, M., Siesjö, B. K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1969
• Subjects: Carbonic acid
• Online Access: http://dx.doi.org/10.1111/j.1748-1716.1969.tb04568.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1748-1716.1969.tb04568.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1748-1716.1969.tb04568.x

Abstract The effect of various doses of acetazolamide upon acid‐base parameters in brain tissue, cisternal CSF and arterial plasma was studied in rats, anesthetized with phenobarbital or nitrous oxide. The results confirmed older findings that carbonic anhydrase inhibition increases the CSF/plasma ratio for bicarbonate, and decreases the corresponding chloride ratio, and showed that the CSF pH remains unchanged during at least 6 hrs in spite of a marked plasma acidosis. The tissue bicarbonate was found to be significantly, but transiently, increased, and since the CSF bicarbonate was essentially unchanged, the increase in bicarbonate must have occurred in the intracellular phase, i.e. an alkaline shift in the cells. However, both the lactate and the pyruvate concentrations in the tissue were decreased after acetazolamide, suggesting an acidosis. It is discussed if these controversial findings indicate that caibonk anhydrase inhibition gives rise to a carbonic acid acidosis in the brain.