Neural Responses to Injury: Prevention, Protection, and Repair. Neurochemical Protection of the Brain, Neural Plasticity and Repair

摘要

The development of chronic epilepsy is a very serious complication of head injury, neurodegenerative diseases, brain tumors, and exposure to neurotoxic agents. Head injury is often associated with loss of short term memory, indicating trauma to the hippocampal formation, the brain region most commonly associated with epileptic brain damage. Underlying the formation of epilepsy (epileptogenesis) is proposed to be a vicious cycle initiated by the loss of neurons. In an attempt to repair and/or replace lost synaptic connections, the brain can develop aberrant synaptic circuits that permit the propagation and amplification of waves of excitatory neurotransmission, eventually resulting in prolonged or repeated seizures (status epilepticus). The massive amounts of excitatory amino acids released during these episodes can stimulate further neuronal loss (excitotoxic damage), the formation of more aberrant synaptic circuits, and further seizures.