Abstract: Objective To study the metabolic levels of amino acids and biogenic amines in peripheral blood of patients with obstructive sleep apnea (OSA) at multiple time points at night and their clinical significance. Methods A total of 100 OSA patients and 100 healthy subjects admitted to the Fifth Affiliated Hospital of Xinjiang Medical University from January 2020 to April 2022 were selected as the research objects. The healthy subjects were the reference group, and OSA patients were the scientific research group. After admission, the levels of amino acid(γ-GABA), melatonin(MT) and endogenous antioxidant in 2 groups were detected, serum vitamin E(VitE) and vitamin C(VitC) were detected by phenantholine colorimetry, superoxide dismutase(SOD) was detected by xanthine oxidase method, malondialdehyde(MDA) was detected by thiobarbituric acid colorimetry. Nitric oxide synthase(NOS) and nitric oxide reductase(NO) were detected by elisa, and the levels of amino acids, melatonin, endogenous antioxidant and disease severity were compared between the two groups. Results The levels of γ-GABA and MT in the research group were lower than those in the reference group, and the differences were statistically significant (P<0.05). The levels of VitE, VitC, SOD, MDA, NOS and NO in the research group were higher than those in the control group, and the differences were statistically significant (P<0.05). With the gradual aggravation of the patient’s condition, the index values of γ-GABA and MT decreased gradually, while the index values of VitE, VitC, SOD, MDA, NOS and NO increased gradually, the difference was statistically significant (P<0.05). Conclusion The low expression of amino acids, melatonin and high expression of endogenous antioxidants in OSA patients at night are directly related to the severity of the disease. Therefore, the above results can provide reference for the treatment of the disease and are worthy of clinical application.

Key words: obstructive sleep apnea, amino acids in peripheral blood, biogenic amine metabolism, correlation