Law-Tho D, Crepel F, Hirsch J C
CNRS URA 1121, Laboratoire de Neurobiologie et Neuropharmacologie du Développement, Université Paris-Sud, Orsay, France.
Eur J Neurosci. 1993 Nov 1;5(11):1494-500. doi: 10.1111/j.1460-9568.1993.tb00217.x.
The effects of noradrenaline on pyramidal cells of layer V of the prefrontal cortex were examined in rat brain slices in vitro. Bath administration of noradrenaline (10 microM) reduced synaptic transmission of afferent inputs from layer 1. The decrease affected all the components of the evoked response and particularly the monosynaptic excitatory postsynaptic potential (EPSP) as evidenced by a reduction of its initial rising slope (mean slope: 71 +/- 11% of its control). Pharmacological dissociation of the NMDA- and non-NMDA-receptor components of the EPSP showed that noradrenaline reduced both (mean EPSP slopes were 71 +/- 8% and 73 +/- 10% of their control, respectively). Alpha 1-, but not alpha-2- or beta-adrenoceptor antagonists prevented the noradrenaline-induced decrease in synaptic efficacy. However, the effect of noradrenaline was not reproduced by alpha 1-adrenoceptor agonists. Lastly, noradrenaline acting through beta-adrenoceptors reduced the slow hyperpolarization that follows a train of action potentials.
在体外大鼠脑片中研究了去甲肾上腺素对前额叶皮质第V层锥体细胞的影响。浴槽给药去甲肾上腺素（10微摩尔）可减少来自第1层传入输入的突触传递。这种减少影响了诱发反应的所有成分，尤其是单突触兴奋性突触后电位（EPSP），其初始上升斜率降低证明了这一点（平均斜率：为对照的71±11%）。对EPSP的NMDA和非NMDA受体成分进行药理学解离表明，去甲肾上腺素使两者均降低（平均EPSP斜率分别为对照的71±8%和73±10%）。α1-肾上腺素能受体拮抗剂而非α2-或β-肾上腺素能受体拮抗剂可阻止去甲肾上腺素诱导的突触效能降低。然而，α1-肾上腺素能受体激动剂不能重现去甲肾上腺素的作用。最后，通过β-肾上腺素能受体起作用的去甲肾上腺素减少了一串动作电位后的缓慢超极化。
