Autonomic Pharmacology part 1 Flashcards
Sympathetic fibers have what postganglionic receptors
Adrenergic (alpha and beta) with Norepinephrine as the neurotransmitter
- Parasympathetic –> Muscarinic receptors
In what 5 ways might drugs modify the ANS activity?
Any of the events associated with neurotransmitters:
- Synthesis
- Storage
- Release
- Receptor interaction
- Disposition (termination of neurotransmitter activity at synapse = enzyme degradation or reuptake)
T or F, Both divisions of the ANS can be affected by the 4 groups of drugs designed for the ANS
True
4 groups of drugs that alter the ANS
- Parasympathetic (PANS) stimulatory
- Parasympathetic (PANS) inhibitory (blocking)
- Sympathetic (SANS) stimulatory
- Sympathetic (SANS) inhibitory (blocking)
How are the drugs affecting the ANS named?
cholinergic - drug that acts at the location where ACETYLCHOLINE is released
Adrenergic - drug that acts at the location where NOREPINEPHRINE is released
parasympatho- = drug that acts where PANS acts sympatho- = drug that acts where SANS acts
When do you name a drug -“mimetic”
When a drug that acts at the location where a division of the ANS acts and produces the same effect as the neurotransmitter
- ** Also known as an agonist drug
A drug that acts at the location where a division of the ANS acts and blocks the action of the neurotransmitter is named?
has the suffix -lytic or - blocker
- Also known as antagonists = no drug effect. they just block receptor site like a plug
Parasympathetic (PANS) drugs
Stimulatory
- cholinergics
- parasympathomimetics
Inhibitory
- anticholinergics
- parasympatholytics
- cholinergic blockers
Sympathetic (SANS) drugs
Stimulatory
- adrenergics
- sympathomimetics
Inhibitory
- adrenergic blockers
- sympathetic blockers
- sympatholytics
2 types of cholinergic agonists
- Direct acting
- act at the acetylcholine receptor
- Indirect acting
- causes the release of acetylcholine
- Cholinesterase inhibitors = cause accumulation of ACH = stimulating PANS
5 characteristics about Direct Acting Cholinergic Drugs
- Act like acetylcholine on receptors
- Agonists
- LONGER duration of action
- MORE SELECTIVE in the effects produced
- SIMULATE the PANS
To an effective mediator, ACh must fit a receptor how?
Physically and Chemically
How do ACh receptors play a role in differences in the response of the receptor to drugs
- There are differences among receptors that have ACh as their neurotransmitter
- Subtypes of ACh receptors are located in different synapses
- Other factors:
- Amount of ACh released
- Size of synaptic cleft
- Tissue penetration of a drug
Pharmacologic Effects of Cholinergic Drugs
- Cardiovascular (bradycardia, decreased BP and cardiac output)
- Eye (produce Miosis, Decreases intraocular pressure
- GI (Excites smooth muscle of gut; Increase in activity, motility and secretion)
T or F, Cholinergic drugs decrease the activity of the GI
False, increase and excite smooth muscle
Primary indications for Direct Acting Cholinergic drugs
- *Glaucoma
- *Myasthenia graves (autoimmune disease)
- GI disorders (increase GI motility)
- Reverse urinary retention after surgery
5 examples of Direct Acting Cholinergic Agonists
- acetylcholine (Miochol) - eye surgery
- bethanechol (Urecholine) - urinary retention
- carbachol (Miostat) - glaucoma
- *cevimeline (Evoxac) - Sjogren’s syndrome
- *pilocarpine (Salagen) - glaucoma, Sjogren’s syndrome
Role of pilocarpine in treatment of glaucoma
By causing pupil constriction, allows for drainage of fluid from the eye through the canal of Schlem
- Glaucoma is increased intraocular pressure due to fluid accumulation
Other than opthalmically, how is pilocarpine used in dentistry?
To stimulate salivary secretions in patients with xerostomia
- for patients with Sjogren’s syndrome or salivary gland damage from head and neck irradiation
What is another drug similar to pilocarpine (in the same class) and is used for salivary stimulation in patients with Sjogren’s syndrome?
cevimeline (Evoxac)
What class of drugs are also known as “cholinesterase inhibitors”?
Indirect-Acting Cholinergic Drugs