Review: Animal models of acquired epilepsy: insights into mechanisms of human epileptogenesis

In many patients who suffer from epilepsies, recurrent epileptic seizures do not start at birth but develop later in life. This holds particularly true for epilepsies with a focal seizure origin including focal cortical dysplasias and temporal lobe epilepsy (TLE). TLE most frequently has its seizure onset in the hippocampal formation. Hippocampal biopsies of pharmacoresistant TLE patients undergoing epilepsy surgery for seizure control most frequently reveal the damage pattern of hippocampal sclerosis, that is, segmental neuronal cell loss and concomitant astrogliosis. Many TLE patients report on transient brain insults early in life, which is followed by a ‘latency’ period lacking seizure activity of months or even years before chronic recurrent seizures start. The plethora of structural and cellular mechanisms that convert the hippocampal formation to become chronically hyperexcitable after a transient insult to the brain are summarized under the term epileptogenesis. In contrast to the obstacles arising for experimental studies of epileptogenesis aspects in human surgical hippocampal tissue, recent animal model approaches allow insights into mechanisms of epileptogenesis. Relevant models of transient brain insults in this context comprise several distinct types of lesions including excitoxic status epilepticus (SE), electrical seizure induction, traumatic brain injury, induction of inflammatory processes by hyperthermia and viral inflammation and others. In pathogeneti...
Source: Neuropathology and Applied Neurobiology - Category: Neurology Authors: Tags: Review Source Type: research