Doxycycline could aggravate the absence-like epileptic seizures of WAG/Rij rats via matrix metalloproteinase inhibition

► Matrix metalloproteinases (MMPs) are activated in the brain by epileptic seizures. ► MMP-9 activity is also elevated in the genetically absence epileptic WAG/Rij rat. ► Doxycycline increased the epileptic spike-wave-discharges (SWDs) in this rat. ► Broad-spectrum MMP inhibitor GM6001 (i.c.v.) also increased the SWDs in this rat. ► MMP inhibition could aggravate the absence epileptic activity.