Kuczewski Nicola, Aztiria Eugenio, Domenici Luciano
Scuola Internazionale Superiore di Studi Avanzati, S.I.S.S.A., Settore di Neuroscienze Cognitive, Via Beirut 2-4, Trieste 34014, Italy.
Brain Res. 2006 Jun 20;1095(1):43-50. doi: 10.1016/j.brainres.2006.04.022. Epub 2006 May 30.
Despite the evidence that cortical synaptic organization and cognitive functions are influenced by the activity of the cholinergic system during postnatal development, so far no information is available on the effects produced by acetylcholine (ACh) on synaptic transmission. In the present article, we show that the ability of visual cortex slices to respond to ACh depends on postnatal age. In adulthood, ACh exerts mainly a facilitatory action on synaptic transmission, depressing field potential (FP) amplitude only if applied at high concentrations (millimolar range). During early postnatal development, at postnatal day 13 (P13), facilitation by ACh was lacking, with depression of FP observed with concentration of ACh in the micromolar range. The magnitude of ACh facilitatory effects increases with age. The time course of ACh-dependent facilitation overlaps the developmental maturation of acetylcholinesterase (AChE), suggesting a close relationship between ACh action and AChE activity. Thus, age-dependent modification of the cholinergic modulatory action may affect cortical maturation by regulating the magnitude of synaptic transmission.
尽管有证据表明，在出生后发育过程中，皮质突触组织和认知功能受胆碱能系统活动的影响，但迄今为止，关于乙酰胆碱（ACh）对突触传递产生的影响尚无相关信息。在本文中，我们表明视皮质切片对ACh的反应能力取决于出生后的年龄。在成年期，ACh主要对突触传递发挥易化作用，仅在高浓度（毫摩尔范围）应用时才会降低场电位（FP）幅度。在出生后早期发育阶段，即出生后第13天（P13），ACh缺乏易化作用，在微摩尔范围的ACh浓度下可观察到FP降低。ACh易化作用的幅度随年龄增长而增加。ACh依赖性易化的时间进程与乙酰胆碱酯酶（AChE）的发育成熟重叠，表明ACh作用与AChE活性之间存在密切关系。因此，胆碱能调节作用的年龄依赖性改变可能通过调节突触传递的幅度来影响皮质成熟。
