Noradrenaline is a neurotransmitter involved in various brain functions including sleep/wakefulness, consciousness, stress/emotional responses, and cognition/memory. The locus ceruleus (LC) is the largest of several noradrenergic nuclei in the brain. Degeneration of the nigro-striatal dopaminergic neurons is the primary cause of motor symptoms of Parkinson's disease, but marked loss of the LC noradrenergic neurons is also observed simultaneously. A research group led by Professor Keiichi Itoi at Graduate School of Information Sciences and Graduate School of Medicine, Tohoku University and Professor Kazuto Kobayashi at Fukushima Medical University has developed a method of destroying noradrenergic neurons in the LC selectively by injection of a recombinant immunotoxin [anti-Tac(Fv)-PE38] into the LC of transgenic mice which express human interleukin-2 receptor alpha-subunit (Tac) under the promoter of dopamine beta-hydroxylase. Following ablation of the LC noradrenergic neurons, mice showed increased anxiety-like and depression-like behaviors. These results were published in Journal of Neuroscience on April 20, 2011. The paper's title is "Targeting of Locus Ceruleus Noradrenergic Neurons Expressing Human Interleukin-2 Receptor Alpha- Subunit in Transgenic Mice by a Recombinant Immunotoxin anti-Tac(Fv)-PE38: A Study for Exploring Noradrenergic Influence upon Anxiety-Like and Depression-Like Behaviors". This research raises a possibility that degeneration of locus ceruleus may be involved in the pathogenesis of anxiety and depression in Parkinson's disease, supporting previous clinical data that anxiety and depression, the major non-motor symptoms of Parkinson's disease, are related to the loss of LC noradrenergic neurons.

[Contact]

Professor Keiichi Itoi

Graduate School of Information Sciences, Tohoku University

TEL: +81-22-795-4741, FAX: +81-22-795-4765

E-mail: itoik*m.tohoku.ac.jp (Replace * with @)