Minocycline-conditioning brings surveying and reactive microglial cells to an alerted state according to their potassium channel profile

Abstract

Microglial cells, the macrophages of the central nervous system (CNS), are key players during inflammatory processes in the CNS and are characterized by the expression of several types of voltage-gated potassium (Kv) channels, such as the delayed rectifying potassium (Kdr) current in reactive microglial cells. This Kdr current has been reported as a physiological marker for microglial activation and is an important target to control microglial activities. In this study we investigated whether minocycline, a known microglial activation inhibitor, was able to inhibit the functional expression of this Kdr current. Therefore, the I/V relationships and the function of the Kv channels of primary cultured rat microglial cells were measured using the whole-cell patch-clamp technique. The I/V profiles were compared in control and lipopolysaccharide (LPS)-activated (100 ng/ml) microglial cells in absence and presence of minocycline (400 µg/ml).