Kametani H, Iijima S, Spangler E L, Ingram D K, Joseph J A
Molecular Physiology and Genetics Section, Nathan W. Shock Laboratories, Gerontology Research Center, National Institute on Aging, Baltimore, MD 21224, USA.
Neurobiol Aging. 1995 Jul-Aug;16(4):639-46. doi: 10.1016/0197-4580(95)00047-i.
A microdialysis probe was implanted into the striatum of young (4- to 5-month-old) and aged (26- to 27-month-old) Fischer 344 male rats to assess age-related alterations in striatal dopamine (DA) release. Basal levels of DA and the magnitude of DA response evoked by 50 mM and 100 mM high potassium (K+) in aged rats were similar to those in young rats. Furthermore, K(+)-evoked DA release did not correlate with motor performance within either age group. In contrast, amphetamine (250 microM) evoked-DA release of aged rats was significantly lower than that of young rats. Moreover, the enhancement of K(+)-evoked DA release by oxotremorine (500 microM) was significantly attenuated in aged rats. These results indicate that a putative DA release mechanism and its cholinergic modulation of the aged striatum are impaired.
将微透析探针植入年轻（4至5个月大）和老年（26至27个月大）的Fischer 344雄性大鼠的纹状体中，以评估纹状体多巴胺（DA）释放的年龄相关变化。老年大鼠的DA基础水平以及由50 mM和100 mM高钾（K +）诱发的DA反应幅度与年轻大鼠相似。此外，K（+）诱发的DA释放在两个年龄组中均与运动表现无关。相比之下，老年大鼠由苯丙胺（250 microM）诱发的DA释放明显低于年轻大鼠。此外，在老年大鼠中，氧化震颤素（500 microM）对K（+）诱发的DA释放的增强作用明显减弱。这些结果表明，老年纹状体中假定的DA释放机制及其胆碱能调节受损。
