Effects of interleukin-1ß on cortical spreading depolarization and cerebral vasculature

During brain damage and ischemia, the cytokine interleukin-1s is rapidly upregulated due to activation of inflammasomes. We studied whether interleukin-1s influences cortical spreading depolarization, and whether lipopolysaccharide, often used for microglial stimulation, influences cortical spreading depolarizations. In anaesthetized rats, cortical spreading depolarizations were elicited by microinjection of KCl. Interleukin-1s, the IL-1 receptor 1 antagonist, the GABAA receptor blocker bicuculline, and lipopolysaccharide were administered either alone or combined (interleukin-1s + IL-1 receptor 1 antagonist; interleukin-1s + bicuculline; lipopolysaccharide + IL-1 receptor 1 antagonist) into a local cortical treatment area. Using microelectrodes, cortical spreading depolarizations were recorded in a non-treatment and in the treatment area. Plasma extravasation in cortical grey matter was assessed with Evans blue. Local application of interleukin-1s reduced cortical spreading depolarization amplitudes in t...