Huntington's Disease (RE-UPLOAD) | Pathogenesis, Signs/Symptoms, and Detailed Mechanism

The video provides an in-depth look at Huntington's disease, starting with its pathophysiology and the role of the Huntington protein. It explains how genetic variations in the number of CAG repeats can affect the onset and severity of the disease. The video details how misfolded proteins lead to neuron degeneration, particularly in the basal nuclei, causing symptoms like chorea. It reviews the direct and indirect pathways of the basal nuclei and how Huntington's disease disrupts these pathways, leading to increased movement and muscle contraction.

What is the primary cause of Huntington's disease?

• A viral infection

• Abnormalities in the Huntington protein

• Environmental factors

• A deficiency in dopamine

How many CAG repeats are considered normal in the Huntington gene?

• More than 40

• Less than 10

• 27 to 35

• 10 to 26

What happens to the Huntington protein when there are too many CAG repeats?

• It breaks down into smaller proteins

• It misfolds and aggregates

• It becomes more stable

• It becomes inactive

Which type of neurons are primarily affected by the aggregation of mutant Huntington protein?

• Pyramidal neurons

• Medium spiny neurons

• Purkinje cells

• Motor neurons

What are the initial symptoms of Huntington's disease?

• Loss of vision

• Severe muscle pain

• Cognitive and psychological issues

• Severe headaches

What is chorea, a symptom of Huntington's disease?

• Loss of balance

• A type of muscle rigidity

• Involuntary jerking or writhing movements

• Difficulty swallowing

What is the role of the direct pathway in the basal nuclei?

• Controlling hormone release

• Regulating sensory input

• Inhibiting muscle contraction

• Promoting muscle contraction and movement

Which structure in the brain is responsible for inhibiting the thalamus in the indirect pathway?

• Putamen

• Caudate nucleus

• Globus pallidus internus

• Substantia nigra

How does Huntington's disease affect the indirect pathway of the basal nuclei?

• It increases the activity of the subthalamic nucleus

• It enhances the inhibition of the thalamus

• It reduces the inhibition of the thalamus

• It has no effect on the thalamus

What is a common motor symptom of Huntington's disease due to its effect on the basal nuclei?

• Muscle weakness

• Paralysis

• Increased muscle contraction and movement

• Loss of muscle tone