Shores M M, White S S, Veith R C, Szot P
Geriatric Research, Education and Clinical Center (GRECC), VA Puget Sound Health Care System, 1660 S. Columbian Way (182B), Seattle, WA 98195, USA.
Brain Res. 1999 Apr 24;826(1):143-7. doi: 10.1016/s0006-8993(99)01200-7.
In normal aging, cell loss occurs in the locus coeruleus (LC), the major noradrenergic nucleus in the brain. This study examined changes in the LC of aged rats by measuring mRNA expression for tyrosine hydroxylase (TH) and the norepinephrine uptake transporter (NET). TH and NET mRNA expression were measured by in situ hybridization in young, middle-aged and aged rats. It appears that in middle age, the transporter system responds initially to LC cell loss by decreasing NET mRNA expression. Then, with further aging and cell loss, TH mRNA expression increases which may potentially increase NE synthesis in the remaining neurons. These findings suggest that multiple regulatory components are used to maintain stable noradrenergic synaptic levels despite neuronal loss. Published by Elsevier Science B.V.
在正常衰老过程中，脑内主要的去甲肾上腺素能核团蓝斑（LC）会出现细胞丢失。本研究通过测量酪氨酸羟化酶（TH）和去甲肾上腺素摄取转运体（NET）的mRNA表达，来检测老年大鼠蓝斑的变化。通过原位杂交技术测量了年轻、中年和老年大鼠TH和NET的mRNA表达。结果显示，在中年时，转运体系统最初通过降低NET的mRNA表达来应对蓝斑细胞丢失。然后，随着进一步衰老和细胞丢失，TH的mRNA表达增加，这可能会潜在地增加剩余神经元中去甲肾上腺素的合成。这些发现表明，尽管存在神经元丢失，但仍有多种调节成分用于维持稳定的去甲肾上腺素能突触水平。由爱思唯尔科学出版社出版。
