Birkenfeld A, Ben-Zvi A
Clin Exp Immunol. 1984 Mar;55(3):651-4.
Cyclic adenosine monophosphate (cAMP) levels of isolated human peripheral blood lymphocytes show age associated changes. These changes are apparent in basal cAMP levels as well as in cAMP levels after trypsin treatment. Both cord blood lymphocytes and lymphocytes isolated from the blood of old people exhibit lower basal levels of cAMP and diminished increase in cAMP by trypsin treatment, in comparison to lymphocytes isolated from the other age groups. The results seem to indicate a low number of reactive cells and a low reactivity of the cells in the case of cord blood lymphocytes, and a decrease in number of the reactive cells without a decrease in specific reactivity of isolated lymphocytes of old people.
分离出的人外周血淋巴细胞的环磷酸腺苷（cAMP）水平呈现出与年龄相关的变化。这些变化在基础cAMP水平以及胰蛋白酶处理后的cAMP水平中都很明显。与从其他年龄组分离出的淋巴细胞相比，脐带血淋巴细胞和从老年人血液中分离出的淋巴细胞均表现出较低的基础cAMP水平，并且经胰蛋白酶处理后cAMP的增加量减少。结果似乎表明，脐带血淋巴细胞的反应性细胞数量少且细胞反应性低，而老年人分离出的淋巴细胞反应性细胞数量减少，但特异性反应性并未降低。
