A client asks the nurse what causes Parkinson disease. Which description of pathology would the nurse provide in response to the client?

A client asks the nurse what causes Parkinson disease. Which description of pathology would the nurse provide in response to the client?

• A. Disintegration of the myelin sheath
• B. Breakdown of upper and lower neurons
• C. Reduced acetylcholine receptors at synapses
• D. Degeneration of neurons of the basal ganglia

Answer: (D)

Parkinson disease pathology centers on the loss of dopamine-producing neurons in the substantia nigra, a part of the basal ganglia that coordinates movement. When these neurons degenerate, dopamine in the striatum decreases, upsetting the balance between the direct and indirect pathways that control movement. This disruption leads to the characteristic motor symptoms—bradykinesia, rigidity, resting tremor, and slowed movement. The other descriptions don’t fit PD. Demyelination describes diseases like multiple sclerosis, where the myelin sheath is damaged. Breakdown of upper and lower motor neurons points to motor neuron diseases such as ALS. Reduced acetylcholine receptors at synapses occur in myasthenia gravis, affecting the neuromuscular junction. In PD, the defining issue is degeneration of basal ganglia neurons, particularly dopaminergic neurons in the substantia nigra.

Parkinson disease pathology centers on the loss of dopamine-producing neurons in the substantia nigra, a part of the basal ganglia that coordinates movement. When these neurons degenerate, dopamine in the striatum decreases, upsetting the balance between the direct and indirect pathways that control movement. This disruption leads to the characteristic motor symptoms—bradykinesia, rigidity, resting tremor, and slowed movement.

The other descriptions don’t fit PD. Demyelination describes diseases like multiple sclerosis, where the myelin sheath is damaged. Breakdown of upper and lower motor neurons points to motor neuron diseases such as ALS. Reduced acetylcholine receptors at synapses occur in myasthenia gravis, affecting the neuromuscular junction. In PD, the defining issue is degeneration of basal ganglia neurons, particularly dopaminergic neurons in the substantia nigra.