TWO DIVISIONS OF THE ANS

kaelihamlen1 — 2022-06-18 16:49:41 UTC

1. Sympatheic Nervous System( Adrenergic System)
2. Parasympathetic Nervous System(Cholinergic System)
3. The Neurotransmitters in the Sympathetic Nervous System are
a)NE (Norepinephrine)
b)EPI (Epinephrine)
c)DA (Dopamine)
The Neurotransmitters in the Parasympathetic Nervous System are
a)ACH(Acetylcholine)
4. The Neurotransmitter ACH is released at the ganglia from the presynaptic nerve endings in both systems.
NE (Norepinephrine) is released at the postganglionic nerve endings and released by the adrenal medulla and neurons
EPI (Epinephrine) acts on adrenergic receptors and produced by the adrenal medulla
DA (Dopamine) is a sympathetic and CNS neurotransmitter which stimulates alpha, beta, and dopaminergic receptors.
5. During Sympathetic Stimulation there is the release of EPI and some NE by the adrenal medulla.The NE is released by postganglionic nerve endings. The following organs are affected:
A) Adrenal Medulla- release of epinephrine(EPI)
B) Arteries-There is vasoconstriction except for coronary arteries and arteries of the skeletal muscles which are dilated
C) Heart- increases heart rate and AV conduction. Also increases contractility
D) Intestines, GI mobility, Secretions- Decreased
E) Postganglionic neurotransmitter- Norepinephrine released
F)Pupil of the Eye-Dilation (Mydriasis)
G) Respiratory Passages (lower)- Bronchodilation
H)Urinary Bladder- Relaxation
I) Urinary Sphincter- Contraction
During the Parasympathetic Effects:
A) ACH is released
B) Heart- Decreased heart rate and AV conduction (atrial ventricular) there is a slight decrease in contractility.
C) Intestines, GI mobility, and secretions- Increased digestion
D)Postgaglionic neurotransmitter-ACH released
E) Pupil of the Eyes- Constriction (miosis)
F) Respiratory passages, lower- bronchoconstriction
G) Urinary Bladder- Contraction, increased urination and defacation
H) Urinary Sphincter-relaxation
6. Drug Classifications for each Division of the ANS:
A) Sympathomimetics- they are drugs that mimic they sympathetic system
1) Adrenergic-alpha-1 receptor is stimulated, contractions of smooth muscle blood vessels constrict, increases blood pressure. Vasoconstriction of nasal passages (decongestant)
2) Agonists- stimulaties all alpha and beta receptors. Vasoconstriction, increases blood pressure, cardiac stimulant, bronchodilator.
B) Sympatholytics- drugs that work against the sympathetic system
1) adrenergic blocking-binds to alpha-1 receptors and blocks them.
*Epinephrine (Adrenalin®)
Relaxation of smooth muscle and vasodilation of blood vessels.Decreases Blood Pressure. It also relaxes smooth muscle of ureters and increases the urine flow.
* prazosin (Minipress®) Hypertension
* terazosin ( Hytrin®) Hypertension, Benign Prostatic Hyperplasia
* doxazosin ( Cardura®) Hypertension, Benign Prostatic Hyperplasia
Beta-1 Adrenergic Agonist: dobutamine
Beta-2 Adrenergic Agonists:
* albuterol (Proventil®, Ventolin®)
* terbuat
2) blockers
3) inhibitors
3) antagonists
Parasympathomimetics- drugs that mimic the parasympathetic system(agonists, cholinergic)They stimulate and bind to the muscarinic receptors in the parasympathetic division
Parasympatholytics- drugs that work against parasympathetic system (antagonists, anticholingerics)
Drugs: Paraympathomimetics DIRECT-ACTING
ACH-used for miosis, cataracts and other eye surgeries. The MOA is pupil constriction
*pilocarpine (Pilocar®) MOA is pupil constriction, decreases the amount of fluid in the eyes and intraocular pressure.
*bethanechol ( Urecholine®) used for urinary retention and ileum and intestinal stasis
The drugs MOA is that it stimulates muscarinic receptors of the bladder and GI tract to prevent constipation and urinary retention post-op and in the elderly
INDIRECT-ACTING CHOLINERGIC AGONISTS
MOA- inhibit acetylcholinesterase which is an enzyme that destroys ACH in the synapse.
-increases ACH
DRUGS: neostigmine (Prostigmin®) urinary retention and intenstinal stasis
anticholinergicrocuronium bromide (Zemuron®) increasing ACH at the nicotinic receptors on skeletal muscle, treatment of myasthenia graves
>ANTIDOTE FOR OVERDOSE OF ANTICHOLINERGICS: physostigmine(Eserine®)

PARASYMPATHOLYTICS MOA- BIND TO A CHOLINERGIC RECEPTOR, ACTS AS A BLOCKING DRUG:COMPETITIVE ANTAGONISM
>DRUGS<

atropine- antidote for cholinergic poisoning

increases HR, decreases vagus nerve activity (parasympathetic)

dicyclomine (Bentyl®) used for GI disorders(ulcers, colitis, IBS)

decreases GI secretions and motility

ipratroprium bromide (Atrovent®) bronchodilation

SOURCES
unit 2, Autonomic Nervous System Part 2, Hitner text.

unit 2, Autonomic Nervous System Part 1, Hitner text.

DISCUSSION BOARD UNIT 2 by Kaeli Hamlen

TWO DIVISIONS OF THE ANS