The Role of Excitatory Aminoacids and its Neurotoxic Impact in Severe Head Injury Patients

Background: Knowledge on metabolic aspects is essential for a better understanding of new pharmacological avenues and non-pharmacological strategies. Traumatic brain injury results in changes the composition of cerebrospinal fluid (CSF), which may represent a unique clinical window on brain pathophysiology. The role of excitotoxicity in mechanically-induced cell death and the molecular events that excessive release of glutamate induce, including apoptosis and delayed inflammatory processes, are shown to be vital to determine the out come of the head injury. Besides, brain injury induces an inflammatory response and production of oxygen-derived reactive species which affect many organs including heart, brain, kidney and gastrointestinal tract. Method: Lumber CSF obtained from 33 patients with severe head injury was collected and HPLC was used for the quantification of aspartic acid and glutamic acid. Kit methods were used for the determining the enzyme activity of LDH. AKP, SGOT, SGPT and CPK by Microlab instrument. For comparison, CSF samples from 32 healthy subjects without any neurological defects were used. Similar protocol was followed for both patients and healthy subjectsResults: Aspartic and Glutamic acid are both increased significantly in patients with severe head injury. Among the enzyme analyzed, LDH and CPK both are increased and s-GPT or ALT decreased significantly. There is no change observed in AST and AKP.Conclusion: From this study besides the role of excitatory amino-acids, the impact on enzyme activities shows a clear sign on the affect of cardial enzymes due to severe head injury. This information may be of vital importance in treating these patients with antagonists in suppressing the levels of glutamic and aspartic acids.