Saint Petersburg, St. Petersburg, Russian Federation
The skin of amphibians and other isolated epithelial systems are classical model objects for studying transepithelial ion transport mechanisms. In terms of their ability to transport electrolytes and their response to certain hormones, the skin and bladder of amphibians are similar to the distal renal tubules, which makes it possible to use the data obtained on these objects to elucidate the mechanisms of water and ion transport in kidney cells. Arachidonic acid (AA) and its metabolites act as signaling molecules involved in the processes of intra- and intercellular signaling, and have a wide range of physiological and pathological effects. In the kidneys and other reabsorbing epithelium, including the frog skin epithelium, AA and its derivatives are involved in ion and water transport regulation. In this regard, it seemed appropriate to investigate the possible role of the cyclooxygenase pathway of AA oxidation in Na+ transport regulation in frog skin. In experiments we used a non-selective cyclooxygenase inhibitor diclofenac, a derivative of phenylacetic acid, which is widely used in clinical practice as a non-steroidal anti-inflammatory drug. Using voltage-clamp technique, we have shown for the first time on the frog skin epithelium that diclofenac (25 μg/ml) inhibits Na+ transport. The degree of diclofenac inhibitory effect on Na+ transport differs depending on the application of the agent from the apical or basolateral skin surface. The results obtained in this work and earlier indicate the involvement of cyclooxygenases and / or products of the cyclooxygenase pathway of AA oxidation in Na+ transport regulation in frog skin epithelium.
frog skin, transepithelial Na+ transport, сyclooxygenase, diclofenac
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