Pedunculopontine nucleus: An integrative view with implications on Deep Brain Stimulation

• Main Authors: Andreas Nowacki, Salvatore Galati, Janine Ai-Schlaeppi, Claudio Bassetti, Alain Kaelin, Claudio Pollo
• Format: Article
• Language: English
• Published: Elsevier 2019-08-01
• Series: Neurobiology of Disease
• Subjects: Deep Brain Stimulation; Gait disorders; Pedunculopontine; Nucleus; Review
• Online Access: http://www.sciencedirect.com/science/article/pii/S096999611830487X

The pedunculopontine nucleus (PPN) is a reticular nucleus located in the mesencephalic and upper pontine tegmentum. Initially, characterized by its predominant cholinergic projection neurons, it was associated with the “mesencephalic locomotor region” and “reticular activating system”. Furthermore, based on histopathological studies, the PPN was hypothesized to play a role in the manifestation of symptoms in movement disorders such as Parkinson's disease (PD). Since axial symptoms represent unmet needs of PD treatments, a series of pioneering experiments in Parkinsonian monkeys promoted the idea of a potential new target for deep brain stimulation (DBS) and much clinical interest was generated in the following years leading to a number of trials analysing the role of PPN for gait disorders. This review summarizes the historical background and more recent findings about the anatomy and function of the PPN and its implications in the basal ganglia network of the normal as well as diseased brain. Classical views on PPN function shall be challenged by more recent findings. Additionally, the current role and future perspectives of PPN DBS in PD patients shall be outlined.