PNS content Flashcards
Ways drugs affect the CNS
synthesis storage release binding prevent the normal destruction and uptake
acetylcholine
parasympathetic receptors and muscarinic receptors on sweat glands in sympathetic
norepinephrine
sympathetic receptors
epinephrine
from adrenal medulla. only one that activates beta 2 receptors.
parasympathetic (cholinergic) receptors
muscarinic
nicotinic
sympathetic
alpha 1 and 2
beta 1 and 2
dopamine
classified as adrenergic
responses only to dopamine.. mostly works in CNS
nicotinic receptors/ response
nicotinic(n)- release of epi from adrenal medulla
nicotinic (m)- contraction of skeletal muscle
muscarinic
increased glandular secretions contraction of smooth muscle slowing of HR contraction of sphincter muscle of iris contraction ciliary muscle of eye voiding of urinary bladder
alpha-1
adrenergic receptors
eyes, BLOOD VESSELS, male sex organs, prostatic capsule, and bladder
alpha-2
adrenergic receptor
located in nerve terminals and not on organs
regulates transmitter release
beta-1
adrenergic receptor
heart and kidney
increase HR, increase force of contraction, increased velocity of impulse through AV node
Kidney: increase renin –> angiotensin –> vasoconstriction
beta-2
adrenergic receptor
LUNGS bronchodilate, uterus relaxation, blood vessels vasodilate, promote glycogenolysis
dopamine
dilates renal blood flow and increases perfusion
prototype or parasympathetic stimulation
Bethanechol (urecholine)
bethanechol (urecholine)
stimulates smooth muscle contraction in the GI and urinary system.
give 1 hr before meals
SE of bethanechol
abd discomfort, diarrhea, nausea, salivation, vomiting, flushing, sweating, hypotension, brady
prototype of anticholinergic/muscarinic antagonist
atropine
atropine
blocks PNS actions of ach and induces symptoms of fight or flight
uses of atropine
increase HR in brady, dilate pupils during eye exams (mydriasis), irritable bowel syndrome, suppress secretions during surgical procedures
se of atropine
drowsiness, blurred vision, photophobia, increase intraocular pressure, tachy, dry mouth, constipation, urinary retention, anhidrosis
od drug for atropine
physostigmine
s/s of atropine OD
blockade of sweat glands– fever
blind as a bat– pupils unable to constrict in bright light
dry as a bone– salivary glands blocked
mad as a hatter– agitation and hallucinations
catecholamine agents
can’t be used orally due to rapid degradtion
brief duration of action
cannot cross the BBB (polar molecules)
noncatecholamine agents
longer half life and metabolized slower
given orally
crosses BBB
prototype of adrenergic agonist
epinephrine
epinepherine characteristics
activates alpha 1 & 2, beta 1 & 2.
therapeutic uses: cardiac arrest, anaphylaxis, hemostasis, bronchodilation, vasoconstriction.
AE of epinepherine
hypertensive crisis, dysrhythmias, angina, necrosis from extravasion, hyperglycemia
prototype of adrenergic antagonists for alpha receptors specifically
prazosin (minipress)
Prazosin (minipress) characteristics
used to decrease BP by working on the vascular smooth muscle in the arterioles and veins
used to tx HTN
also used for pts with urinary outflow problems from BPH
SE of prazosin
first dose orthostatic hypotension, dizziness, weakness, headache, reflex tachy, nasal congestion
prototype of adrenergic antagonist
propranolol (inderal LA)
propanolol (inderal LA)
blocks both beta 1 & 2
therapeutic uses: HTN, angina, cardiac dysrhythmias, MI
SE of propanolol
brady, AV heart block, heart failure, rebound cardiac excitation, bronchoconstriction, inhibits glycogenolysis, CNS effects.
