Bellinger D L, Ackerman K D, Felten S Y, Felten D L
Department of Neurobiology and Anatomy, University of Rochester School of Medicine, New York 14642.
Exp Neurol. 1992 Jun;116(3):295-311. doi: 10.1016/0014-4886(92)90009-f.
A longitudinal study of sympathetic noradrenergic (NA) innervation of the spleen was carried out in 3-, 8-, 12-, 17-, 21-, and 27-month-old Fischer 344 (F344) rats using (i) fluorescence histochemistry for localization of norepinephrine (NE); (ii) immunocytochemistry (ICC) for localization of tyrosine hydroxylase (TH)-positive nerve fibers alone, and in combination with specific markers for T and B lymphocytes (OX19 and anti-mu respectively), and macrophages (ED3); and (iii) high-performance liquid chromatography with electrochemical detection for quantitation of NE. Fluorescence histochemistry revealed extensive loss of NA nerve fibers in all compartments of the spleen in 21- and 27-month-old rats. With single-label ICC, a decline in TH+ nerve fibers in all compartments of the spleen was observed by 17 months of age and became more severe with advancing age; these findings suggest that both the rate-limiting enzyme and the transmitter itself (NE) are depleted from sympathetic nerves in aged rat spleen. Double-label ICC demonstrated the loss of TH+ nerve fibers in spleen from 17-, 21-, and 27-month-old rats, and a parallel loss of OX19+ T lymphocytes and ED3+ macrophages in these cellular compartments. Neurochemical measurement of NE demonstrated a decline in NE per wet weight at 27 months of age. The age-related decline in NA innervation of spleen and in the density of specific populations of cells of the immune system (T lymphocytes and antigen-presenting ED3+ macrophages), that follow remarkably similar time courses, supports functional evidence for dynamic interactions between the immune system and NA sympathetic nerves in the spleen, and further suggests a causal relationship between these age-related phenomena, i.e., that age-related immunosenescence promotes sympathetic denervation of the spleen which further compromises immune function. This hypothesis, however, requires further testing.
利用以下方法，对3、8、12、17、21和27月龄的Fischer 344（F344）大鼠的脾脏交感去甲肾上腺素能（NA）神经支配进行了一项纵向研究：（i）采用荧光组织化学法定位去甲肾上腺素（NE）；（ii）采用免疫细胞化学法（ICC）单独定位酪氨酸羟化酶（TH）阳性神经纤维，并与T和B淋巴细胞的特异性标志物（分别为OX19和抗μ）以及巨噬细胞（ED3）联合使用；（iii）采用高效液相色谱电化学检测法定量NE。荧光组织化学显示，21和27月龄大鼠脾脏所有区域的NA神经纤维大量减少。单标记ICC显示，到17月龄时，脾脏所有区域的TH+神经纤维数量下降，且随着年龄增长变得更加严重；这些发现表明，老年大鼠脾脏交感神经中的限速酶和递质本身（NE）均减少。双标记ICC显示，17、21和27月龄大鼠脾脏中TH+神经纤维减少，且这些细胞区域中OX19+ T淋巴细胞和ED3+巨噬细胞数量也相应减少。NE的神经化学测量显示，27月龄时每湿重NE含量下降。脾脏NA神经支配以及免疫系统特定细胞群（T淋巴细胞和抗原呈递ED3+巨噬细胞）密度随年龄的下降呈现出非常相似的时间进程，这支持了脾脏中免疫系统与NA交感神经之间存在动态相互作用的功能证据，并进一步表明这些与年龄相关的现象之间存在因果关系，即与年龄相关的免疫衰老促进了脾脏的交感神经去支配，进而进一步损害免疫功能。然而，这一假设还需要进一步验证。
