L15- pharmacology of drugs to treat Parkinson’s disease

What is parkisons

A progressive disorder of movement

What i the main age of parkinsons patients

Mainly elderly (+65)

What does it mean by PD being idiopathic

The cause is unknown

What is the characteristic cause of PD

Degeneration of dopaminergic neurone of the nigrostriatal tract + loss of dopaminergic neurotransmission in the striatum

What do typical PD patients have

Lewy bodies

Lewy bodies

Aggregates of alpha synuclein proteins in the neurons of the brain

Parkinsonism

Any condition with loss of striatal dopaminergic transmission or atypical PD

Examples of things that can cause parkisonism

Drugs, stroke, infection induced symptoms

Atypical PD

Features in addition to typical PD symptoms

Motor symptoms of PD (4)

• resting tremor

• Muscle rigidity

• Suppression of voluntary movements

• Shuffling gait with short steps

What is PD regarded as

A neurological disorder with a motor phenotype

What can PD cause problems with over time (7)

• movement

• Anosmia

• Mental health

• Sleep

• GI disruption

• Pain

• Other health issues

Ansomia

Loss of sense of smell

How is PD characterised

Loss of dopaminergic neurons/ cell bodies in the substantia nigra

What do PET images of PD patients show

Loss of DA terminals in the striatum

What do healthy people compared to PD patients have

Healthy have lots of dopamine precursors in substantia nigra

Dopamine PD pathology (2)

• degeneration of DAergic neurons of the nigrostriatal tract

• Loss of DA neurotransmission in the striatum

Dopamine parkinsonism pathology (2)

• any condition with loss of DA transmission in striatum

• Pharmacological blockade→ brain lesion etc

Where is dopamine primarily synthesised (3)

• In the substantia nigra (SN)

• The ventral tegmental area (VTA)

• Hypothalamus

Where do projections from the SN go to and what does it form

Go from SN to striatum to form nigrostriatal pathway

Where do projections from the VTA go to and what does it form

From teh VTA to the cortex to form the mesocortical pathway

What does the hypothalamus project to, from and regulate

Projects to the pituitary to form the tuberoinfundibular pathway where it functions to regulate prolactin release

What does the nigrostriatal pathway control

Movement

what is the mesocortical pathway and what does it in control

Ventral tegmental area to the nucleus accumbens → controls motivation and emotion

What makes up the mesolimbic pathway and what does it control

Ventral tegmental area to frontal cortex → controls reward

What is the tuberoinfundibular pathway and what does it control

Arcate nucleus to pituitary gland → controls pituitary

What is the pharmacotherapeutic aim with PD

To increase DA neurotransmission in the striatum