Parkinsons Disease

Ageing, it increases with the ageing population

About the same as for people without the disease. for some people symptoms evolve slowly over 20 years

Nigrostrial tract - control and coordination of sensory stimuli and movement. Mesolimbic system - cognitive, reward and emotinal behaviour. tuberoinfundibular system-neural control of hypothalamic pituitary endocrine system

The nigrostrial pathway

Resting tremor Rigidity; sometimes jerky, stiff muscles. face dead pan cos facial muscles rigid Akinesia/Bradykinesia; slowness getting dressed, eating. Also speech very slow and monotonous; no intonation. Gait; small steps Postural instability; shoulders go up head goes down

Constipation, erectile dysfunction, urinary incontinence, hyposmia, depression, anxiety

L-DOPA; GOLD STANDARD DA antagonists eg apomorphine Agents that prolong the effects of L -DOPA derived dopamine eg MAO-b inhibitor

A precursor of dopamine, it passes through the blood brain barrier and is metabolised to dopamine in dopaminegic neurons

MAO-b monoamine oxidase b inhibitor, metabolises dopamine which is primarily found in glial cells that are located close to dopaminergic neurons

Surgical strategies; pallidotomy, thalamotomy, deep brain stimulation

Psychosis, nausea and vomiting, sudden sleep attacks, peripheral effects

Pallidotomy, and thalamotomy-invasive surgery, irreversible. Require specialist centres

They bind to post synaptoc dopamine receptors and thus appear to mimic the action of dopamine in the synaptic cleft

The benefits of the drug persist for many hours or even days after discontinuation of treatment. As the disease progresses even in moderate disease, the long duration response to levadopa diminishes and pts begin to experience a reemergence of their PDs symptoms

The benefits of levadopa therapy "on" time becomes increasingly associated with side effects such as dyskinesia