Pharmacological and physiological effects of magnesium on experimental traumatic brain injury

It is now generally accepted that in addition to mechanical or primary injury to the central nervous system (CNS) resulting from a traumatic event, much of the irreversible neural injury occurring after CNS trauma is caused by secondary factors. One of the secondary injury factors implicated in the development of irreversible tissue injury, and associated mortality and morbidity after neurotrauma, is magnesium. This review focuses on recent evidence suggesting that magnesium plays a critical role in the injury process, not only by having direct effects on cellular metabolism, but also by regulating other proposed secondary injury factors such as excitatory amino acids, calcium, lipid hydrolysis, opioid peptides, and energy metabolism. Treatments that have a demonstrated neuroprotective effect following neurotrauma are shown to restore brain cellular magnesium homeostasis after injury.