Antiparkinson agent

An antiparkinson medication is a type of drug which is intended to treat and relieve the symptoms of Parkinson's disease. Most of these agents act by either increasing dopamine activity or reducing acetylcholine activity in the central nervous system.

Parkinson's disease is a motor system disorder of the nervous system. It is outlined as a progressive disorder that affects movement and results in the loss of dopamine-producing brain cells, causing tremor in the hands, arms, legs, jaw, and face and/or rigidity or stiffness of the limbs and trunk. The primary symptoms are muscular rigidity, slowness of movement, a resting tremor, and postural instability. Parkinson’s disease is caused by degeneration of the nigrostriatal system, which is the dopamine-secreting neurons of the substantia nigra that send axons to the basal ganglia. The basal ganglia controls the automatic, habitual responses performed by the human body.

It is difficult to diagnose Parkinson’s disease, as there is no specific test for it. Doctors usually perform other tests in order to rule out other conditions. Often seen in the dopaminergic neurons in the brains of patients who have Parkinson’s disease, are Lewy bodies, which are abnormal circular structures found within the cytoplasm. Lewy bodies have a dense protein core, surrounded by a halo of radiating fibers. Mutations on chromosome 4 can cause Parkinson’s disease. This gene produces a protein known as a-synuclein. This protein which is normally found in the presynaptic terminals and is thought to be involved in synaptic transmission in dopaminergic neurons. The mutation produces what is known as a toxic gain of function because it produces a protein that results in effects that are toxic to the cell. Parkinson’s disease can also be caused by a mutation on chromosome 6. This gene has been named parkin. This mutation causes a loss of function, which makes it a recessive disorder.

The goal of the most common Antiparkinson drugs is to either replace the dopamine levels in the brain, or mimic the actions of dopamine. The main categories of Antiparkinson drugs are anticholinergic drugs and dopaminergic drugs. Anticholinergic drugs block the action of acetylcholine, compensating for the low levels of dopamine. As stated before, dopaminergic drugs aim to replace dopamine or inhibit the degradation of dopamine in the brain.

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