Pars reticulata

Pars reticulata is a part of the basal ganglia system in the brains of vertebrates, located above the substantia nigra. It is one of the major output centers for the basal ganglia, along with the pars interna. The pars reticulata and the pars interna together form the substantia nigra.

Etymology

The term "pars reticulata" is derived from Latin, where "pars" means part and "reticulata" means reticulated or net-like. This refers to the net-like appearance of this part of the brain due to the presence of a large number of densely packed cells.

Structure

The pars reticulata is composed of GABAergic neurons, which are inhibitory in nature. These neurons receive input from the striatum and the subthalamic nucleus, and send output to the thalamus. The output is inhibitory, which means it reduces the activity of the target neurons in the thalamus.

Function

The main function of the pars reticulata is to control and regulate movements. It does this by inhibiting the activity of the thalamus, which is involved in motor control. The pars reticulata also plays a role in eye movements and in the control of attention.

Clinical significance

Damage to the pars reticulata can lead to movement disorders such as Parkinson's disease and Huntington's disease. In Parkinson's disease, there is a loss of dopamine-producing neurons in the pars reticulata, which leads to an overactivity of the thalamus and an underactivity of the motor cortex. This results in the characteristic symptoms of the disease, such as tremors, rigidity, and bradykinesia (slowness of movement).

See also

• Basal ganglia
• Substantia nigra
• Parkinson's disease
• Huntington's disease