RESUMO
Objective: To investigate the circadian ryhthm variation of 2 125 I iodomelatonin ( 125 I Mel) binding sites in the human peripheral leukocytes in patients with acute cerebral infarction. Methods: Melatonin binding sites in the human peripheral leukocytes were studied using 125 I Mel as a radioligand (radioligand binding assays).All patients [age: (70.18? 11.70) years] were diagnosed by CT according to the standard [Chin J Nerv, 1996,29(6):379]. We also studied 15 age matched healthy old people as the control [age: (68.33?7.76) years]. Results: The circadian ryhthm variation of 125 I Mel specific binding in control remained significant ( P 0.05). The specific binding in the peripheral leukocytes at midlight in the patients with acute cerebral infarction were lower than that of the control. Conclusion: The expression of Mel receptor decreases in the patients with acute cerebral infarction and the circadian ryhthm variation of 2 125 I Mel appears abnormal.