Pitts D K, Freeman A S, Chiodo L A
Laboratory of Neurophysiology, Sinai Research Institute, Detroit, Michigan.
Synapse. 1990;6(4):309-20. doi: 10.1002/syn.890060402.
The ontogeny of nigrostriatal dopamine (NSDA) neurons was examined with single-unit extracellular electrophysiological methods. The physiological and pharmacological characteristics of 2-, 4-, and 5-week-old rat pup NSDA neurons were compared with those of adults (8-10 weeks old). Although the basal discharge rate, conduction velocity, and firing pattern of NSDA neurons from 4- and 5-week-old rats were similar to adults, the 2-week-old-rats differed significantly in all three of these physiological characteristics. The conduction velocity and basal discharge rate were found to be significantly lower in the 2-week-old pups relative to adults. In addition, there were significantly fewer bursting NSDA neurons in 2-week-olds than there were in adults. Two and 4-week-olds exhibited significantly lower sensitivity to cumulative intravenous doses of apomorphine. In contrast, the sensitivity to cumulative intravenous doses of quinpirole was found to be similar across all age groups. It is evident that the pharmacological and physiological properties of NSDA neurons are in a dynamic state of flux during postnatal development. These electrophysiological findings are discussed in the context of the perinatal development of midbrain DA systems.
采用单单位细胞外电生理方法研究黑质纹状体多巴胺（NSDA）神经元的个体发生。将2周龄、4周龄和5周龄大鼠幼崽的NSDA神经元的生理和药理特性与成年大鼠（8 - 10周龄）的进行比较。尽管4周龄和5周龄大鼠的NSDA神经元的基础放电率、传导速度和放电模式与成年大鼠相似，但2周龄大鼠在这三个生理特性上均有显著差异。相对于成年大鼠，2周龄幼崽的传导速度和基础放电率显著更低。此外，2周龄大鼠中爆发性放电的NSDA神经元明显少于成年大鼠。2周龄和4周龄大鼠对阿扑吗啡累积静脉注射剂量的敏感性显著较低。相比之下，发现所有年龄组对喹吡罗累积静脉注射剂量的敏感性相似。显然，NSDA神经元的药理和生理特性在出生后发育过程中处于动态变化状态。在中脑多巴胺系统围产期发育的背景下讨论了这些电生理发现。
