Basic Concepts

Question 1

what NT is in what ganglion?

Answer 1

parasympathetic and sympathetic ganglion: both use nicotinic ACh. parasympathetic post G = muscarinic ACh. sympathetic post G = NA

Question 2

three ANS divisions

Answer 2

sympathetic, parasympathetic, and intrinsic (enteric and intracardiac)

Question 3

ANS originally regarded as what kind of system? now know it contains what components (3)?

Answer 3

efferent system. now: contains afferent, central and efferent components

Question 4

all neres leaving CNS release? all afferent fibers are?

Answer 4

release ACh. are excitatory.

Question 5

post ganglionic terminal axons are characterized by? def?

Answer 5

varicosities: swellings of the axon that occur every few microns

Question 6

what accumulates in caricosities?

Answer 6

synaptic vesicles with NTs

Question 7

two categories of receptors

Answer 7

ionotropic aka ligand gated ion channels. metabotropic aka linked to a G protein and second messenger system.

Question 8

ionotropic receptor: produces what? aka?

Answer 8

production of post synpatic current = EPSP or IPSP. aka intrinsic sensor receptor, because binding site is on same molecule as channel

Question 9

metabotropic receptor: structure? produces? aka?

Answer 9

7 TM domains or heptahelical. initiates a signal transduction cascade via G-proteins + 2ndary messengers. aka remote sensor receptors.

Question 10

in peripheral autonomic nerves: which two primary NTs?

Answer 10

ACh for ganglia and parasympathetic. NA for sympathetic.

Question 11

in peripheral autonomic nerves: 4 other small molecules?

Answer 11

5HT, ATP, NO, DA

Question 12

in peripheral autonomic nerves: 7 neuropeptide examples?

Answer 12

NPY, VIP, CGRP, Substance P, galanin, SRIF, leucine and methionine enkephalin (opioid peptides)

Question 13

autocoids: aka? released by? examples?

Answer 13

local hormones, released by neurons or target tissue in response to local signals. histamine, prostaglandins, leukotrienes, other eicosinoids, substance P, 5HT, ATP, NO

Question 14

smaller vs. larger vesicles and what they contain

Answer 14

smaller: biogenic amines (ACh, NA) only. larger: both biogenic amines and peptides

Question 15

smaller and larger vesicles both contain? which can also? regualtion?

Answer 15

ATP, which can also act as a co-transmitter. differentially regulated

Question 16

NANC?

Answer 16

non-adrenergic, non-cholinergic nerves, and their responses are mediated by ATP or peptides

Question 17

chemical coding means?

Answer 17

different autonomic nerves to different peripheral targets are often characterized by the peptide that they contain

Question 18

plurichemical transmission means?

Answer 18

autonomic nerve releases a combo of 2+ NTs, so as to affect broad control of the target tissue

Question 19

how do we get tissue specific ANS signals?

Answer 19

targeted innervation, presynpatic chemical coding, different post synaptic receptor subtypes

Question 20

most important aspect of ANS control of viscera =?

Answer 20

selective and independent control of different vascular beds by sympathetic fibers. aka control of blood vessels

Question 21

blood vessel layers

Answer 21

from in to out: tunica intima/endothelium. tunica media/smooth muscle. tunic adventitia/collagen fibers

Question 22

tunica adventicia: contains?

Answer 22

sympathetic nerve terminals and varicosities (also contains collagen fibers)

Question 23

in response to sympathetic stimualtion, blood vessel does what

Answer 23

smooth muscle will contract

Question 24

blood vessels are under what tone?

Answer 24

sympathetic tone; there is very little or no parasympath. innervation of blood vessels

Question 25

endothelium of blood vessels release what to cause what

Answer 25

NO: relaxation, endothelin: contraction of vascular smooth muscle

Question 26

sympathetic nerves affect what kind of vessels

Answer 26

resistance vessels in viscera and skin, so will direct blood supply to where it is needed

Question 27

ANS controls what things of the heart

Answer 27

pacemaker rate of SA node, AV node delay, AP propagation rate, force of contraction of atria and ventricles

Question 28

so overall, ANS controls what two things (heart)

Answer 28

stroke volume (amount of blood ejected from heart per beat) and cardiac output (SV X HR)

Question 29

heart under what tone?

Answer 29

parasympathetic tone

Question 30

heart ganglia: what and where

Answer 30

intracardiac ganglia: intracardiac neuron networks in fat pads around heart