Circadian rhythm of thymosin-alpha 1 in normal and thymectomized mice.

摘要: Studies by many investigators have demonstrated that the immune system is subject to regular circadian fluctuation. Some rhythms been reported include changes in components of system, e.g., lymphocytes, and variation primary secondary responsiveness. The observation these are inversely correlated glucocorticoid rhythm has led suggestion fluctuations may be a result rhythm. This study was designed see if thymosin-alpha 1 (Tsn-alpha 1), 28-amino acid polypeptide isolated from bovine thymus influence thymocyte differentiation, might follow rhythm, thus play role periodicity system. In experiments, groups 10 C57BL/6 or Swiss Webster mice were sacrificed at 4- 6-hr intervals over 24-hr period. Serum Tsn-alpha corticosterone levels determined radioimmunoassay. Results first experiment showed undergoes (p less than 0.001) with an acrophase (time peak levels) 1.5 hr after onset light, amplitude (amount maximum mean) 0.493 ng/ml 1-like immunoreactivity. These results confirmed which animals placed on reversed light cycle. separate experiment, persisted thymectomized 6 mo. earlier. this latter significant increase relative sham-operated controls also observed. Although experiments do not imply casuality, it interesting time can optimal function.