In this graphic the involvement of the dopamine neuronal network in movement is shown. Dopaminergic neurons present in the substantia nigra can either project to neurons in the striatum that use acetylcholine as neurotransmitter or directly affect GABA (gamma-amino-butyric acid) in the Gpi/SNr. The cholinergic neurons pass the signal to GABA-ergic neurons that project
to the globus pallidus. From there the signal is transferred over neurons in the thalamus, motor cortex and spinal cord before finally the muscle cell receives the information to contract.
Gpe: globus pallidus external segment
STN: subthalamic nucleus
Gpi/SNr: globus pallidus internal segment/ substantia nigra pars reticulata
I. Parkinson’s disease is characterized by decreased GABA neurotransmission. II.Parkinson’s disease is characterized by decreased cholinergic neurotransmission.
Extra info: Parkinson’s disease is caused by a decreased dopaminergic neurotransmission, which results in increased cholinergic and GABA-ergic neurotransmission.