Charles River conducts contract studies in trigeminal ganglia electrostimulation and cortical spreading depression (KCl-induced) animal models to assess the efficacy of novel antimigraine drugs. The electrical stimulation of the trigeminal ganglion induces changes in cerebral blood flow (CBF) observed in migraine as well as changes in plasma protein extravasation and levels of CGRP. The chemical induction of cortical spreading depression by application of KCl also induces changes in CBF as well as changes in direct current potential and CGRP release.