MMP-12 Inhibitor Injection in Rat Hippocampus

The hydroxypyrone-based MMP-12 inhibitor was prepared as previously published [15 (link)]. 24 h after SE, rats were anaesthetized with isoflurane and placed on a stereotaxic apparatus equipped with a micro-injector (Quintessential Stereotaxic Injector, Stoelting C.O., Dublin, Ireland). Animals received 1 µL of the MMP-12 inhibitor (2 mM in 10% dimethyl sulfoxide (DMSO, Sigma-Aldrich), in PBS) through the cannula. More precisely, MMP-12 inhibitor was injected in the right hippocampal CA3 radiatum, while the left hippocampal CA3 radiatum served as an internal control. The duration of the injection was 5 min. The cannula was left in place for another 2 min to prevent spill-over. After the injection, the cannula was removed, and animals were left to recover from the anesthesia. These procedures were repeated twice/day for two days.