Atropine

• Background information

• Biological explanation

• Uses in medicine

Background• Atropine is found in many members of the Solanaceae

family of plants

• Mandragora (mandrake) was used in the fourth century

B.C. for treatment of wounds, gout, and sleeplessness

• Roman and Islamic Empires across Europe used

Solanaceae containing tropane alkaloids for

anaesthesia for centuries

• The substance was first synthesized by German chemist

Richard Willstätter in 1901

• The toxic alkaloid atropine

comes from the highly

poisonous Deadly

nightshade, common

name belladonna (Italian

for "beautiful lady")

• Women placed atropine-

containing drops in their

eyes to dilate their pupils,

giving them a dreamy look

that was believed to be

attractive. Tragically, many

of these women later

became blind

Biological explanation

• Atropine is an ANTICHOLINERGENIC drug

• It is called this because it ‘antagonises’ (works

against) acetylcholine.

Atropine as an antagonist Acetylcholine

Atropine

Atropine as an antagonist Acetylcholine

Atropine

Atropine

C17H23NO3

SYNAPSE

Atropine binds

with the receptors

so acetylcholine

can’t

The nerve

impulse cannot

transmit

This function can

be utilised to

‘paralyse’ certain

nerves

Eyes

HeartThe vagus nerve normally slows the heart

Atropine blocks the effect of the vagus nerve by

binding with the acetylcholine receptors on the post –

synaptic membrane

The heart rate is no longer inhibited

This may stimulate the heart

Atropine is give after a heart attack

Metabolism of atropine

• Up to 50% of atropine is excreted unchanged in the

urine

• The remaining Atropine is destroyed by enzymatic

hydrolysis in the liver