Chapter 4 Flashcards
What is the Autonomic Nervous system divided into?
Parasympathetic
Sympathetic
Afferent
Sensory
Efferent
Motor
What cranial nerves are associated with the PANS?
III Oculomotor Nerve VII Facial nerve IX Glossopharyngeal Nerve X Vagus nerve Sacral (S2-S4) segments of spinal cord
Thoracic (T1) to lumbar (L2)
Adrenal medulla
SANS
What are some of the muscles that the PANS affect
Smooth mucles
Cardiac muscles
Glands
What are some of the muscles that the SANS affect?
Heart
Blood vessels
Skeletal muscles
What is Cholinergic also called?
Parasympathomimetic agents
These mimic the PANS
Cholinergic (Parasympathomimetic)
Direct acting (cholinergic)
Acts like acetylcholine at receptor sites
Indirect acting (cholinergic)
Causes increase in amount of acetylcholine indirectly
Inhibits AChE —> Breaks down ACh
Cardiovascular effects from cholinergic direct effects
A decrease in cardiac output is associated with these agents, bradycardia, and decrease in BP
GI effects (cholinergic)
Excite smooth muscles of the GI tract (Diarrhea)
Adverse reactions of cholinergic agents
S= Salivation L= Lacrimation U= Urination D= Defecation
Contraindications of cholinergic agents
Bronchial asthma Hyperthyrodism GI or urinary tract obstruction Severe cardiac disease Peptic ulcer
How is xerostomia treated?
With pilocarpine (Salagen) 5 mg tablet tid
What is Anticholinergic also called?
Parasympatholytic agents
What does anticholinergic agents do ?
- They are cholinergic blocking agents
- Prevents ACh action at postganglionic parasympathetic nerve endings
- Block ACh action on smooth muscle, glandular tissue, and the heart
Antimuscarnic agents
anticholinergic agents
What happens if you increase drug penetration in CNS
You increase the chance of CNS side effects
Anticholinergic effects on exocrine glands
Reduce the flow and volume of secretions
Anticholinergic effects on smooth muscles
- Relax smooth muscle in respiratory tract
- Relax smooth muscle in GI tract
- Spasmolytic agents
Anticholinergic effects on the eye
Mydriasis (dialation)
Cycloplegia (paralized cillary muscles)
Anticholinergic effects on the cardiovascular
- Large doses produce vagal blockade > tachycardia
* Small doses, bradycardia predominates
Anticholinergic adverse reactions
Xerostomia Blurred vision Photophobia Tachycardia Fever Urinary and gastrointestinal stasis Hyperpyrexia Signs of CNS excitation
Contraindications of anticholinergic agents
Glaucoma Prostatic hypertrophy Intestinal obstruction Urinary obstruction or retention Cardiovascular disease
Uses of anticholinergic agents
Postoperative medication Treatment of GI disorders Ophthalmologic examination Reduction of Parkinson like movements Motion sickness
What are some considerations a Dental Hygenist must make when having a patient on anticholinergic agents?
Xerostomia
Tachycardia
Sedation
Neurotransmitters
Communication between nerves or between nerves and effector tissue takes plase by the release of a chemical neurotransmitters across synaptic cleft
Between preganglionic and postganglionic nerves
ACh
Cholinergic
Nicotinic
Between postganglionic nerves and the effector tissues
PANS: ACh, cholinergic, muscarnic
SANS: NE, adrenergic
In the autonomic nervous system, the preganglionic neuron originates in the __________ and passes out to form the ganglia at the __________ with the postganglionic neuron. The postganglionic neuron originates in the __________ and innervates the __________.
central nervous system, ganglia, synapse, effector organ
A drug that has the suffix __________ has the same action as an agonist.
-mimetic
What is the principal neurotransmitter of the PANS?
Acetylcholine
The action of the released acetylcholine is terminated by hydrolysis by what enzyme
Acetylcholinesterase
The two components of the ANS, the sympathetic autonomic nervous system (SANS) and the parasympathetic autonomic nervous system (PANS) together control regulation of which bodily functions?
Regulation of blood pressure and heart rate and smooth muscles of the gut and bronchi
A single preganglionic fiber often synapses with what?
numerous postganglionic neurons to produce a diffuse effect
When the sympathetic autonomic nervous system is stimulated, the __________ releases epinephrine and norepinephrine, acting as a large sympathetic ganglion.
Adrenal Medulla
What is the preganglionic neurotransmitter of the parasympathetic nervous system?
Acetylcholine
What are the primary postsynaptic neurotransmitters for the sympathetic nervous system?
Norepinephrine/epinephrine
Which naturally occurring cholinergic agents is given to stimulate saliva flow?
Pilocarpine