Related Experiment Video
Updated: May 9, 2026
11:58
Primary Culture of Mouse Dopaminergic Neurons
Published on: September 8, 2014
Forebrain dopamine neurons project down to a brainstem region controlling locomotion
Dimitri Ryczko1, Swantje Grätsch, François Auclair
1Groupe de Recherche sur le Système Nerveux Central, Département de Physiologie, Université de Montréal, Montréal, QC, Canada H3C 3J7.
Summary
Researchers discovered a novel descending dopamine pathway from the posterior tuberculum to the mesencephalic locomotor region in lampreys, which modulates locomotion.
Area of Science:
- Neuroscience
- Comparative Biology
- Locomotion Control
Background:
- Dopamine's role in locomotion is linked to ascending pathways to the basal ganglia.
- A recent finding identified dopaminergic innervation in the monkey's mesencephalic locomotor region (MLR).
- The origin and function of this input remained unclear.
Purpose of the Study:
- To investigate the origin and function of a descending dopaminergic pathway to the MLR.
- To explore dopamine's role in locomotion control in a basal vertebrate model.
Main Methods:
- Triple labeling to trace neural projections.
- Electrophysiological recordings and patch-clamping in isolated brain preparations.
- Voltammetry to measure dopamine release.
- Stimulation and microinjection experiments in semi-intact preparations.
Main Results:
- Identified a descending dopaminergic pathway from the posterior tuberculum (PT) to the MLR in lampreys.
- PT stimulation evoked dopamine release and excitatory inputs in MLR neurons, activating reticulospinal cells.
- PT stimulation induced locomotor movements, modulated by D1 receptor activity in the MLR.
Conclusions:
- A descending dopaminergic pathway from the PT to the MLR modulates locomotor output.
- This pathway plays a key role in promoting locomotion by influencing MLR neurons.
- Provides insights into the evolution of dopamine-mediated motor control.
Related Concept Videos
01:19Brainstem
The brainstem, located inferior to the brain and superior to the spinal cord, serves as a bridge between the cerebrum and the spinal cord. It plays a vital role in relaying information and controlling critical life functions. It comprises three primary regions: the midbrain, pons, and medulla oblongata.
The Midbrain
The midbrain is located beneath the diencephalon and connects the cerebrum with the lower parts of the brain. The cerebral peduncles are prominent midbrain structures that house the...
The Midbrain
The midbrain is located beneath the diencephalon and connects the cerebrum with the lower parts of the brain. The cerebral peduncles are prominent midbrain structures that house the...
01:27Diencephalon: Thalamus and Information Relay
The thalamus, often called “the gateway to the cerebral cortex,” is vital in processing and directing sensory and motor signals throughout the brain. Almost all inputs destined for the cerebral cortex, except for olfactory signals, are relayed through the thalamus. The thalamus is a sophisticated relay station, channeling information from various brain regions to the cerebral cortex, as well as a filter, prioritizing certain signals over others based on current physiological states or needs.
01:30Organization of the Brain
The brain is an integral component of the nervous system and serves as the center for processing sensory inputs, making decisions, and directing bodily actions. This complex organ is organized into three primary sections: the hindbrain, midbrain, and forebrain, each responsible for a range of vital functions.
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
01:22Indirect Motor Pathways
The indirect motor or extrapyramidal pathways originate in the brainstem, the lower portion of the brain that connects it to the spinal cord. They consist of several distinct tracts, each with specialized functions. The four main tracts of the indirect motor pathways are the vestibulospinal tract, the reticulospinal tract, the tectospinal tract, and the rubrospinal tract.
The vestibulospinal tract originates in the vestibular nuclei of the brainstem. The vestibular system detects changes in...
The vestibulospinal tract originates in the vestibular nuclei of the brainstem. The vestibular system detects changes in...
01:30Diencephalon: Anatomical Regions
The diencephalon, etymologically translated as 'through brain,' plays an integral role as the conduit between the cerebrum and the vast extent of the nervous system. However, the olfactory system is an exception, as it interfaces directly with the cerebrum. The diencephalon, deeply ensconced beneath the cerebrum, primarily consists of three paired structures — the thalamus, hypothalamus, and epithelamus. It also includes accessory structures such as the subthalamus, which houses the subthalamic...
01:17Cerebellum: Anatomical Regions
The cerebellum, also known as the "little brain," is located in the posterior cranial fossa, inferior to the tentorium cerebelli and dorsal to the brainstem. It plays a significant role in motor control, coordination, and proprioception.
Cerebellar Structure
Externally, the cerebellum features a highly convoluted surface with numerous folia (narrow ridges) separated by shallow sulci (grooves). The cerebellum is divided into two hemispheres by a thin median structure known as the vermis. The...
Cerebellar Structure
Externally, the cerebellum features a highly convoluted surface with numerous folia (narrow ridges) separated by shallow sulci (grooves). The cerebellum is divided into two hemispheres by a thin median structure known as the vermis. The...