Background: A cyclic relationship exists, between; arginine, citrulline, and ornithine. Arginase is a specific enzyme that plays a role in this relationship. These basic amino acids have a role in the induction of nitric oxide (NO) and as anti-inflammatory and antioxidant. This study aimed to elucidate the role of surgical injuries and anesthesia on plasma levels of the above-mentioned amino acids and NO and to determine whether the changes in these levels can be correlated to the duration of surgery and anesthesia exposure.
Materials and Methods: The study included: group A (41 patients) who underwent coronary bypasses and group B (17 patients) who underwent lung cancer surgery. An amino acid analyzer was used for the detection of amino acids, while NO was estimated by a Spectrophotometric method.
Results: The study revealed a significant decrease in the intra-operative levels of arginine, citrulline, ornithine, and NO compared to their pre-operative levels in both groups.
Conclusion: Depletion of these basic amino acids is possibly multifunctional and can be associated with an increase in arginase, surgical trauma, anesthesia, and stress.