CHAPTER FOURTY-SIX AUTONOMIC AND CNS Flashcards
What does PNS stand for
peripheral nervous system
What do afferent neurons do
carries messages to the brain
What do efferent neurons do
carry messages away from the brain
What is the somatic nervous system
voluntary skeletal muscle
What is the autonomic nervous system
involutory organ, gland, and smooth muscle response
what are the two parts of the autonomic nervous system
the sympathetic (adrenergic) and parasympathetic (cholinergic)
what is the goal of the ANS
maintain homeostasis and equilibrium in the body
what is the sympathetic (adrenergic)
fight or flight
what is the parasympathetic
rest and digest
define neurotransmitters
used by the nervous system
define neurohormones
used by the endocrine system
what are the main neurotransmitters
norepinephrine and acetylcholine
define ligand
a binding molecule
define affinity
the level of attraction/binding
what is an antagonist
blocks a physiological response
what is an agonist
can trigger a physiological response
signal transduction
what it is called when a ligand stimulates/blocks a target
response of sympathetic/adrenergic
- increased HR and BP
- increase glucose
- increased mental activity
- pupil dilation (increased sight)
- increased cellular metabolism
- increased blood flow to brain, heart, and muscles
- bronchodilation
- relaxation of bladder
define endogenous
originates within the body
define exogenous
drug therapy
what are catecholamines
SNS neurotransmitters and hormones
common SNS neurotransmitters
norepinephrine, epinephrine (adrenaline), dopamine
facts about norepinephrine
- both a transmitter and hormone
- the body reuses it
-created in nerve endings
-metabolized by MOA and COMT
facts about epinephrine/adrenaline
- made in adrenal glands
-metabolized by MOA and COMT - commonly used for anaphylaxis
facts about dopamine
- found in brain, blood vessels and kidneys
- acts on BP and HR
- commonly used in renal and heart failure
facts about Alpha 1 receptors
- found in smooth muscle in blood vessels, GI and GU
- causes muscle contraction, vasoconstriction and pupil dilation
facts about alpha 2 receptors
- found in brain and pancreas
- inhibits norepinephrine, stopping the sympathetic response
- inhibits insulin release
facts about beta 1 receptors
- found in heart cells
- increases HR and contraction
facts about beta 2 receptors
- found in smooth muscle of lungs, skeletal and urinary
- relaxation of muscles
-bronchodilation
define sympathomimetic
mimics the SNS
define adrenergic agonist
causes SNS response
define adrenergic antagonist
stops SNS response
define sympatholytic
stops SNS response
define adrenergic blocker
stops SNS response
alpha 1 drug uses
nasal congestion, hypotension, dilation of pupils
- treated through vasoconstriction
alpha 2 drug uses
hypertension
- vasodilation and inhibiting insulin release
beta 1 drug uses
cardiac arrest, heart failure, shock
- increases HR and contraction
beta 2 drug uses
asthma, premature labor contractions
- relaxes muscles
what is a selective medication
acts on a specific receptor sight and has less side effects
- ex: selective beta 1 blocker will not effect beta 2
what is a non selective med
acts on more than one receptor type with more side effects
what type of med is phenylephrine
sympathomimetic: stimulates alpha 1
- increases BP
- treats allergies and congestion
what type of med is dopamine
sympathomimetic
- used in renal and heart failure
what type of med is norepinephrine
sympathomimetic: stimulates A1, A2, and B1
what type of med is epinephrine
sympathomimetic
- epi pens
what type of med is midodrine
sympathomimetic: A1
- orthostatic hypotension
what type of med is albuterol
sympathomimetic: selective beta 2
- bronchodilation
what type of med is isoproterenol
sympathomimetic: beta 1 and 2
- increase HR and bronchodilation
side effects of sympathomimetics
- tachycardia, dysrhythmia, chest pain
- hypertension
- CNS excitement (nervous, restless)
- dry mouth (HF and RF)
- nausea and vomiting
-dysuria (painful urination)
contraindications of sympathomimetics
- pheochromocytoma (secretes catecholamines)
- tachy-arrhythmias
- CVD and PVD
-HTN
-thyroid disease
-hypovolemia (low blood volume)
-renal or hepatic issues
interacts with: tcas, maois, herbals, otcs
effects of parasympathetic system/cholinergic
- lower BP and HR
-increased secretions of digestive enzymes
-pupil constriction - contraction of bladder
contraction of skeletal muscle
primary neurotransmitter of parasympathetic/cholinergic
acetylcholine
facts about acetylcholine
- formed in nerve endings
- excitatory effects of nerve synapse
- inhibits effects at peripheral sites
-body recycles
parasympathetic cell receptors
nicotinic (CNS nerves and skeletal muscle)
- activated by Ach
- release epinephrine
- fast and brief response
muscarinic (internal organs)
- activated by Ach
- can be excited or inhibited
-slow and prolonged response
direct acting definition
bind to and activate receptors
- longer duration of action
- widespread effects
indirect acting definition
inhibit AchE
why are cholinergic drugs typically not used
high potential for adverse effects
what do cholinergic drugs commonly treat
myasthenia gravis, Alzheimer’s disease, GI and urinary muscle strength (retention), glaucoma
what is a cholinergic drug
promotes parasympathetic
what is a parasympathomimetic drug
promotes the parasympathetic
what is a cholinergic agonist drug
promotes the parasympathetic
what is a parasypatholytic drug
inhibits the parasympathetic
what is a cholinergic antagonist drug
inhibits the parasympathetic
what is a cholinergic blocker
inhibits the parasympathetic
what type of drug is bethanechol
cholinergic agonist: muscarinic stimulant, direct acting
- increases contraction and promotes bladder emptying
what type of drug is carbachol
cholinergic agonist: direct acting
- decreases intraocular pressure for glaucoma
what type of drug is donepezil
selective AchE inhibitor
- increases levels of Ach, compensate for loss of cholinergic brain cells
-used to treat Alzheimer’s
what type of drug is pyridostigmine
AchE inhibitor
-treats myasthenia gravis
side effects of parasympathomimetics
-nausea, vomiting, loose stool
-increased salivation
-watery eyes
-Headache and dizziness
-bradycardia
-narrowed airway
-urinary urgency
cholinergic drug contraindications
-Urinary and GI obstruction
-asthma
-ulcers
-inflammatory GI
-coronary artery disease
- hyperthyroidism
-pregnancy
+
-hepatic and renal issues
what kind of drug is atropione
anticholinergic
- stimulates HR, reduces salivation, and GI spasms
what kind of drug is dicyclomine/propantheline
anticholinergic
-treats IBS, sweating, uncontrolled bladder and cramping
what kind of drug is meclizine/scopolamine
anticholinergic
-treats vertigo and motion sickness
block Ach
what kind of drug is glycopyrrolate
anticholinergic
-decreases oral secretions for vented and neuro patients
what kind of drug is ipratropium/tiotropium
anticholinergic
-blocks muscle receptors, causes bronchodilation
-for COPD
list common anticholinergic drug uses
-GI disorders
-ophthalmic procedures
-cardiac rhythm disorders
-pre-anesthesia
-asthma
-overreactive bladder
side effects of anticholinergics
tachycardia, HTN
-CNS stimulation
-constipation and urinary retention
-dry mouth and eyes
-inhibition of sweating
-photophobia, blurred vision, increased pressure
-weakness and dizziness
anticholinergic contraindications
-glaucoma
-GI conditions
-enlarged prostate and bladder obstruction
-arrhythmias, tachycardia, Mi
-renal and hepatic issues
- use of antihistamines, antiparkinsonian meds, and monoamine oxidase inhibitor (MAOI) depression med
