Meyer J A, Meyer J D
Arch Surg. 1978 Aug;113(8):972-5. doi: 10.1001/archsurg.1978.01370200066012.
Forty young female rats, aged about 3 months, were weighed on entry into the study; half were subjected to initial splenectomy. Animals were weighed at monthly intervals therafter. Ten animals from each group were killed at four months, and ten from each group at one year. Thymuses and spleens were dissected out and weighted. Because of progressive weight gain, all groups showed declining thymic index. Absolute thymus weight did not change signficiantly in splenectomized animals. Intact animals showed significantly reduced thymus weight at 4 months (P less than .001) and at 12 months (P less than .005). We conclude that the spleen may be a causative factor in the thymic involution of increasing age. The process is gradual and indolent compared to the rapid thymic weight depletion that occurs in the presence of growing tumor.
40只约3月龄的年轻雌性大鼠在进入研究时称重；其中一半接受初始脾切除术。此后每月对动物称重。每组10只动物在4个月时处死，每组10只在1年时处死。取出胸腺和脾脏并称重。由于体重逐渐增加，所有组的胸腺指数均下降。脾切除动物的胸腺绝对重量无显著变化。完整动物在4个月时（P<0.001）和12个月时（P<0.005）胸腺重量显著降低。我们得出结论，脾脏可能是年龄增长导致胸腺退化的一个致病因素。与肿瘤生长时胸腺重量迅速减少相比，这个过程是渐进和缓慢的。
