Week 5 Flashcards
(29 cards)
What are the main transmitters used in the ANS?
- Acetylcholine (Ach)
- Noradrenaline (NA)
What receptors does Ach work on?
Cholinergic receptors
What receptors does NA work on?
Noradrenergic receptors
What are the 5 steps of neuro-transmission?
- Synthesis
- Storage
- Transduction
- Signal Transduction
- Signal Inactivation
What is the enzyme in the synaptic cleft that breaks down Ach?
Acetylcholinesterase
What are the 2 main cholinergic receptors?
Muscarinic
Nicotinic
What are the 2 main adrenergic receptors?
Alpha
Beta
All the junctions coming out of sympathetic system use which receptors?
Nicotinic
All receptors at end organs of Parasympathetic system use which receptors?
Muscarinic
which is excitory and inhibitory with alpha and beta receptors
- alpha - excitatory
- beta - inhibitory (except in the heart - B1 stimulates force of contraction and rate of contraction)
B2 receptors are in the lungs - cause inhibitory as it dilates bronchial smooth muscle
What are the symptoms of botulism
- blurred or double vision
- drooping eyelids
- slurred speech
- difficulty swallowing
- dry mouth
- progressive weakness with paralysis
- fixed or dilated pupils
- maybe constipation
- facial weakness on both sides of face
- breathing difficulty that may lead to resp failure.
What is hypotonia?
Decreased muscle tone
What does botulism do?
prevents the release of Ach into synaptic cleft. Turns off muscle contaction essentially. Causes flaccid paralysis
What are therapeutic uses for botox?
- Bleopharospasm - uncontrolled contraction of eyelids
- Cerebral Palsy - reduce muscle rigidity and uncontrollable spasms
- Hyperhidrosis - abnormal sweating
What are anticholinesterases?
Stops enzymes that breaks down Ach… such as insecticides, sarin nerve gas, organophosphate
Where are organsophosphates usually found?
Pesticides
WHat is the mechanism of action of organophosphates?
Bind strongly to Acetylcholinesterase, inhibiting break down of Ach
- leads to cholinergic overstimulation
- Cam affect both nAChR and mAChR sites
What are the symptoms of organophosphate poisoning?
muscarinic symptoms (SLUDGE):
- Salivation
- Lacrimation
- Urination
- Defecation
- GI cramping
- Emesis
Nicotinic symptoms:
- Muscle cramps
- Tachycardia
- Weakness
- Twitching
- Fasciculations
What are the muscarinic symptoms of organophosphate poisoning?
muscarinic symptoms (SLUDGE):
- Salivation
- Lacrimation
- Urination
- Defecation
- GI cramping
- Emesis
What are the nicotinic symptoms of organophosphate poisoning?
Nicotinic symptoms (MTWTF):
- Muscle cramps
- Tachycardia
- Weakness
- Twitching
- Fasciculations
What are some therapeutic uses for anticholinesterases?
- Myasthenia gravis (NMJ) - destruction of nicotinic receptors
- Alzheimer’s disease (CNS)
What are the side effects of anticholinesterases?
increased salivation, lacrimation, uriniation, diarrhoaea, GI upset
How can an ion channel blockade be caused?
Excessive activation of nicotinic receptors
What would a muscarinic drug do to the parasympathetic nervous system?
Cardiovascular:
- decrease cardiac contraction
- decrease cardiac conduction
- vasodilation
Gastrointestinal:
- increase tone and motility
- relaxation of sphincters
Exocrine glands:
- Increase salivation, lacrimation and sweating
- Increase intestinal & bronchial secretion
Eye:
- pupil constriction
- decrease intraocular pressure in glaucoma
Bronchi:
- bronchoconstriction
