Susceptibility of brainstem to kindling and transfer to the forebrain.

Purpose: The kindling of seizures with stimulation of brainstem sites has been reported inconsistently in the literature. The characteristics of the kindling observed, involving high intensities of stimulation and immediate onset of generalized tonic-clonic convulsions, raise questions regarding the nature of kindling from these sites.

Methods: We implanted chronic electrodes in either the nucleus reticularis pontis oralis (RPO), mesencephalic reticular formation (MRF), dorsal periaqueductal gray (dPAG), or ventrolateral periaqueductal gray (vlPAG) in male Long-Evans rats, with a recording electrode in the amygdala.