Basic Concepts 2 b

Question 1

classical view of the ANS: characteristics of symp vs. para

Answer 1

large diffuse adrenergic sympathetic system, balanced by smaller and more specifically directed cholinergic parasymp. system

Question 2

ganglionic vs. post ganglionic transmission via what NTs and recetpors

Answer 2

ganglionic transmission: ACh on nAChR. post ganglionic parasympathetic effects via mAChR. post ganglionic sympathetic via a and b adrenoreceptors

Question 3

atropine

Answer 3

blocks mAChR so blocks post ganglionic parasympathetic effects

Question 4

two types of alpha receptors and where they are found

Answer 4

a1 on vascular smooth muscle, usually post synpatic. a2 on presynaptic nerve terminals

Question 5

two types of b-adrenoreceptors

Answer 5

B1: heart, more sensitive to NA. V2 in other tissues. B3 has been defined. also have excitatory B autoreceptors on sympathetic nerve terminals

Question 6

adrenoreceptor pharmacology: alpha 1 and 2 what is the order of efficacy for adrenergic ligands?

Answer 6

a1: N>A>I (post synpatic)
a2: A>=N»I (presynpatic)

Question 7

adrenoreceptor pharmacology: beta 1 and 2 what is the order of efficacy for adrenergic ligands?

Answer 7

b1: N>I>A (cardiac)
B2: I>A>N (blood vessels, lungs, etc.)

Question 8

sympathetic NS: size and specificity? innervates?

Answer 8

large and diffuse. innervates every organ in the body apart from skeletal muscle

Question 9

most important aspect of sympathetic nerve activity?

Answer 9

ongoing activity responsible for maintaining autonomic tone in various targets

Question 10

primary role of symp. system

Answer 10

series of precise and differentiated reflex arcs

Question 11

sympathetic system not essential for life when? but insufficiency?

Answer 11

when in a controlled and comfortable enviornment. insufficiency readily apparent under stress: no activation of compensatory responses to cold, hemorrhage, oxygen deprivation, emotional excitement, fatigue, exercise, fright, danger, etc.

Question 12

sympathetic NS just fight or flight?

Answer 12

NO, misconception. SNS is continuously active, diffuse by HIGHLY regulated

Question 13

symp. NS and adrenal system only discharges as a ___ during?

Answer 13

as a unit, during rage and fright such that sympathetically innervated structures are affected simultaneously

Question 14

sympathetic syndrome/flight or fight: what happens

Answer 14

increased HR and BP. blood flow shifted away from skin/planchnic regions towards skeletal muscle. blood glucose rises. pupils and bronchioles dilate.

Question 15

ANS controls ___ (3) as well as specific targets like ___ (3)

Answer 15

exercise, thermoregulation, immune response. specific targets like heart, guts, lungs

Question 16

sympathetic NS is ____ (3 characteristics)

Answer 16

diffuse, constantly activated, highly regulated

Question 17

adrenergic agonists act on what receptors? ACh?

Answer 17

alpha and beta receptors. muscarinic and nicotinic receptors.

Question 18

parasympathetic system organized mainly for _____? contrasts with sympath. system which is?

Answer 18

mainly for localized discharge within a limited number of target tissues aka it is anatomically directed vs. the diffuse and regulated symp. system.

Question 19

parasympsthetic system concerned mostly with what 2 things

Answer 19

conservation of energy. maintenance of organ function during periods of minimal activity

Question 20

activation of parasympathetic nerves: 5 effects

Answer 20

decrease HR. lower BP. stimulates GI movements and secretions. facilitates nutrient absorption. empties bladder/rectum

Question 21

parasympsthetic outflow is directed: because of what (2)

Answer 21

no such thing as parasympathetic syndrome. rapid parasymp. reflex to constrict pupils to protect retina from bright light (and see no other parasymp effects, just one directed localized effect)

Question 22

generally: parasymp = what with muscles? symp = ?

Answer 22

parasymp = relaxation of smooth muscle, secretion. symp = smooth muscle contraction

Question 23

autonomic tone: many visceral organs receive? exceptions?

Answer 23

both parasymp and symp innervation. exceptions: spleen, kidney, blood vessels = only sympathetic

Question 24

liver and fat cells have what innervation

Answer 24

adrenergic sympathetic innervation, perhaps also non cholinergic parasymp innervation

Question 25

two branches of ANS exert _____ effects

Answer 25

opposite, but rarely equal effects on each target tissue

Question 26

exceptions to opposite/not equal effects of P/S systems

Answer 26

male sex organs: two branches of ANS are complimentary (cholinergic = erection, sympathetic = ejaculation). sweat glands and immune system: P + S have similar effects

Question 27

at rest, most targets are under ___?

Answer 27

sympathetic or parasympathetic tone: aka under dominant influence of one or the other branch of the ANS

Question 28

hexamethonium

Answer 28

blocks nAChR receptors in both sympathetic and parasymp systems = ganglion blockade

Question 29

ganglion blockade induces?

Answer 29

parasympathomimetic effects in tissues under sympathetic tone. sympathomimetic effects in tissues under parasymp. tone

Question 30

in general: most tissues receive?

Answer 30

most but not all tissues receive innervation from both the parasympathetic and sympathetic branches of ANS

Question 31

what things exert opposite effects (2 generalizations)

Answer 31

muscarinic receptors/parasympathetic opposite of adrenoceptors/symapthetic nerves in same tissue. a and b adrenoreceptors often exert opposite effects in same tissue.

Question 32

tissue localization and specific effects or receptor subtypes important for? ex?

Answer 32

therapeutics. B-adrenoreceptor agonist for bronchodilation in asthma, need to use selective B2 agonist so you don’t stimulate cardiac B1