Firing activity of locus coeruleus noradrenergic neurons increases in a rodent model of Parkinsonism

Neurosci Bull. 2009 Feb;25(1):15-20. doi: 10.1007/s12264-009-1023-z.

Abstract

Objective: To investigate the changes in the firing activity of noradrenergic neurons in the locus coeruleus (LC) in a rat model of Parkinson disease (PD).

Methods: 2 and 4 weeks after unilateral lesion of the nigrostriatal pathway in the rat by local injection of 6-hydroxydopamine (6-OHDA) into the right substantia nigra pars compacta (SNc), the firing activity of noradrenergic neurons in LC was recorded by extracellular single unit recording.

Results: The firing rate of LC noradrenergic neurons increased significantly 2 and 4 weeks after 6-OHDA lesions compared to normal rats, respectively (P < 0.05). The percentage of irregularly firing neurons was obviously higher than that of normal rats during the fourth week after SNc lesion (P < 0.05).

Conclusion: LC noradrenergic neurons are overactive and more irregular in 6-OHDA-lesioned rats. These changes suggest an implication of the LC in the pathophysiological mechanism of PD.

目的: 观察帕金森病模型大鼠蓝斑核肾上腺素能神经元电活动的改变。

方法: 在黑质致密部局部注射6-羟多巴胺损毁右侧黑质纹状体通路后, 采用细胞外记录方法分别于损毁术后第2周和第4周观察大鼠蓝斑核肾上腺素能神经元的电活动变化。

结果: 6-羟多巴胺损毁术后第2周和第4周, 蓝斑核肾上腺素能神经元放电频率比对照组显著增加(P < 0.05)。 损毁术后第4周, 蓝斑核呈不规则放电的神经元比例显著高于对照组(P < 0.05)。

结论: 6- 羟多巴胺损毁术后, 大鼠蓝斑核肾上腺素能神经元活动增强, 且更不规则, 提示蓝斑核参与帕金森病的发病。

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology*
  • Animals
  • Disease Models, Animal
  • Locus Coeruleus / pathology*
  • Male
  • Neurons / physiology*
  • Norepinephrine / metabolism*
  • Oxidopamine
  • Parkinsonian Disorders / chemically induced
  • Parkinsonian Disorders / pathology*
  • Rats
  • Rats, Sprague-Dawley
  • Time Factors

Substances

  • Oxidopamine
  • Norepinephrine