【摘要】 本文报道小鼠注射醋酸考的松后,再注射小牛胸腺素,胸腺细胞中腺苷脱氨酶活性的升高比对照组有提前和增大幅度的作用。而小鼠胸腺细胞在体外与胸腺素保温后,腺苷脱氨酶活性比对照组降低。实验还证实分化较早期的胸腺细胞中腺苷脱氨酶活性比分化较成熟的胸腺细胞大3倍,胸腺细胞腺苷脱氨酶活性比外周血淋巴细胞大5倍,从而支持腺苷脱氨酶是胸腺细胞分化成熟标志酶的观点。更多还原

【Abstract】 The effect of several calf thymosin preparations, including simplified thymosin, calf thymosin fraction 5 (1-3) and calf thymosin fraction 5 presented by Dr. Goldstein, on adenosine deaminase (ADA) activity in mouse thymus cells were studied in vivo and in vitro. In vivo study, both the control mice and studied mice were similarly injected with 2. 5mg of cortisone acetate intraperitoneally to cause thymus atrophy. Then the studied mice were injected with thymosin preparations simultaneously and during the successive 10 days. The ADA activity in thymus cells of the studied group increased much earlier and larger to a greater extent than that of the control. In vitro study, the ADA activity in thymus cells of the studied group decreased more significantly than that of the control group after the thymus cells of mice were mixed with thymosin preparations and incubated at 37℃ for 4 hrs. By using the discontineous gradient centrifuge to divide the mouse thymus cells into fractions of high density and low density cells, it was demonstrated that the higher ADA activity occurred primarily in the high density cell fraction which is inma-ture, whereas the activity of ADA in the low density cell fraction which is quite mature was lower. In addition, we also discovered that the ADA activity in the peripheral blood lymphocytes was lower than that of thymus cells. It suggested that the ADA mihgt act as a marker-enzyme in judging the differentiation and maturation of thymus cells. The effect of thymosin preparations on ADA activity in thymus cells may correlate with the differentiation of thymus cells. Finally, it is also thought that the method described here can be used to assay the biological activities of thymosin preparations.更多还原