Ação da prednisona e prednisolona sobre o canal para potássio Kv1.3

Abstract

Ion channels are integral proteins on cell membrane that form pores in the lipid bilayer, allowing the selective passage of ions. Ion channels play roles in multiple physiological processes, such as muscle contraction; memory and learning; release of neurotransmitters and hormones; control of cell proliferation, among others. Voltage-gated potassium channels are present in the plasma membrane of virtually every cell and are responsible for the resting potential, the repolarization phase of the action potential, and the control of cell proliferation. Voltage-gated potassium channels KV1.3 are expressed in the plasma membrane of T lymphocytes and are recognized as promising targets in the therapeutic treatment of autoimmune diseases, since these channels play pivotal role in the activation and proliferation of T lymphocytes. Autoimmune diseases are associated with an exacerbated immune reaction mediated by T lymphocytes. KV1.3 channels blockers are known as immunomodulating agents and their use as therapeutic target has shown great efficacy in the treatment of these pathologies. Among drugs that are used in the treatment of autoimmune diseases, prednisone and prednisolone, synthetic corticoids, were studied to analyze the electrophysiological changes caused by these drugs on KV1.3 channels, showing that both could promote significant, direct, and reversible blockade of the potassium currents flowing through the KV1.3 channels. There are no studies demonstrating interactions between these corticosteroids and KV1.3 channels, so investigating these interactions contributes to the outlining of the mechanisms involved in the response of these drugs in autoimmune diseases.