Flashcards in Lecture 6 - Cholinergic Agonists Deck (45)
______ receptors use ion channels
nicotinic affects ganglion of both ___ and ___
nicotinic affects _____ muscle
Muscarinic receptors are _____ mediated
What do muscarinic receptors affect ?
effector organs/tissues of parasympathetic
Sweat receptors on the ____ are adrenergic
Sweat receptors everywhere else are ____
cholinergic (but still part of sympathetic system)
All preganglionic synapses are _____
Skeletal muscle works through ___ receptors
Does ACh cross the BBB
-so there are no psychological effects
What does ACh activate?
-all autonomic ganglia (sympathetic and parasympathetic)
-skeletal muscle receptors
What does Pilocarpine do?
-very similar to ACh but it CAN penetrate BBB
What is pilocarpine the drug of choice for?
severe acute glaucoma (intraocular pressure)
-it causes immediate opening of drainage system of the eye
-also used for fixed focus
What does AChE do? (acetylcholinesterase)
degrades Ach in the synapse
What will inhibition of AChE do?
It will increase the activity of ACh in the synapse
i.e. it will have a cholinergic agonist effect
-increased activation of the parasympathetic NS
What is myasthenia gravis?
it is autoimmune destruction of Ach receptors at NMJ (neuromuscular junction)
What type of drugs can help with myasthenia gravis?
drugs which increase ACh activity can aid the symptoms
(no underlying pathology)
*this is a short term solution because you are only increase Ach of the receptors that are left
*eventually all receptors will die because that is a characteristic of this condition
What is alzheimer's disease?
cholinergic neurons in brain undergo reduced activity and then die
How can you treat alzheimer's disease?
You can administer drugs which can increase ACh activity in the brain can therefore treat some symptoms of AD, but not underlying pathology
Neostigmine is a ??
How does neostigmine work?
-stimulates the bladder and GI tract (used for urinary bladder disease and constipation)
-it can also aid in symptoms of myasthenia gravis (it increases muscular strength and response)
Donepazil (Aricept) is a ?
How does Donepazil (Aricept) work?
stimulates cholinergic neurons in brain
-can be used to treat symptoms of alzheimer's disease
Atropine is a ??
(an antagonist of the parasympathetic nervous system)
Atropine = ____
belladonna (beautiful woman)
Atropine does what?
-decreases CV response to parasympathetic stimulation
(heart rate increases and BP rises)
-bronchodilation and decreased respiratory sections
-antispasmodic effect on GI tract and other smooth muscles
Neocitran is a ??
Neocitran is an antihistamine and therefore ?
decreases parasympathetic nerve activity
What are a few side effects of antihistamine?
-sedation and drying (atropinic)
What does a sympathomimetic do?
obvs increase sympathetic receptor activity
Who should not be taking Neocitran?
-can cause cardiovasculation issues (hypertension, MI)
-can cause GI and GU issues (constipation and urinary retention)
-strong CNS effect
-most-effective anti-nausea drug
-derived from atropine
-inhaled bronchodilators (long-term effect)
What are some overdose/side effects of blocking cholinergic system
-sandy eye syndrome
-loss of near vision
-dry pasty saliva
-no movement, but sustained acid - causes nausea, vomiting, constipation, pain
Bladder: flaccid bladder, constricted sphincter
But you won't care - cause you're paralyzed
Main ingredients: belladonna alkaloids, atropine, scopolamine
-extracts of it used in treating asthma, intestinal cramps, diarrhea and bed-wetting
red as a beet
dry as a bone
blind as a bad
mad as a hatter
What are NMJ blockers used for?
used in surgery
-it reduces the amount of anesthesia needed, allows rapid recovery of senses
-they are injected IV
What is the order of muscular paralysis?
eyes, face, fingers, limbs, trunk, diaphragm
Order of recovery from muscular paralysis?
diaphragm, trunk, limbs, fingers, face, eyes
NMJ blockers can be...?
non-depolarizing or depolarizing
How can NMJ blockers cause paralysis?
-therefore a risk of paralysis
Curare is ??
an NMJ blocker
-it is amazonian poison
-no longer used
Is curare non-depolarizing or depolarizing?
Succinylcholine is ??
an NMJ blocker
-causes twitching and fasciculation at first (from depolarization) but then flaccid paralysis