WEEK 6

Question 1

what effectors express alpha receptors

Answer 1

Vasoconstriction (α1)
Iris dilation (α1)
Intestinal relaxation (α1)
Intestinal sphincter contraction (α1) Bladder sphincter contraction (α1) Liver glycogen breakdown (α1) Inhibits neurotransmitter release (α2)

Question 2

what effectors express beta receptors

Answer 2

Vasodilation (β2)
↑heart rate (β1)
↑ cardiac force contraction (β1) Intestinal relaxation (β2)
Uterus relaxation (β2) Bronchodilation (β2)
↑ glycogen breakdown (β2) Bladder wall relaxation (β2)

Question 3

fill in.
Adrenergic receptors bind _______ and _______

Answer 3

norepinephrine or epinephrine.

Question 4

what are the two subtypes of adrenergic receptors?

Answer 4

GPCR: α and β

Question 5

Fill in.
α1 are widely expressed on ________; Interacts with __________ ; activation causes __________. Found on cells ___________ and activation causes reduction in__________. Causes contraction of radial muscles of ________(dilation)

Answer 5

arteries/arterioles; Gαq/IP3/DAG : vasoconstriction; juxtaglomerular : renin release; iris

Question 6

Fill in.
α2 are not widely distributed; interacts with _______; found in ________ where it mediates _________ feedback on sympathetic outflow and on presynaptic terminals (↓NE release). On platelets (stimulates aggregation). Beta cells (decreases insulin secretion)

Answer 6

Gαi ; brainstem : negative

Question 7

Fill in.
β1 Interacts with_______; expressed in _____; increases _______ and force of _______. Found on cells of the ________ kidney; activation increases _______ .

Answer 7

Gαs; heart ; heart rate ; contraction; juxtaglomerular renin secretion

Question 8

Fill in.
β2 Interacts with_____; expressed on ________; cause _________ and vasodilation b/c smooth muscle relaxation

Answer 8

Gαs; bronchioles ; bronchodilation

Question 9

Fill-in .
β3 Interacts with_____; found on postsynaptic effector cells in ______ and ________ ; similar effects to β1

Answer 9

Gαs; lipocytes; myocardium

Question 10

sympathetic activation of the heart causes

Answer 10

Increased heart rate and stroke volume, dilation of coronary arteries

Question 11

what is the purpose of the fight, flight, or freeze reaction

Answer 11

• delivery oxygen and glucose to working skeletal muscles

Question 12

what happens in the heart, respiratory system, metabolic system, sweat glands, and eyes in fight, flight or freeze reaction

Answer 12

Cardiac:
- heart rate, contractility increase to increase cardiac output
- Blood vessels: Vascular smooth muscle contracts causing widespread vasoconstriction.
- blood redirected to working muscles

Respiratory:
- bronchial dilation

Metabolic:
- increases glycogenolysis (glycogen break down) and gluconeogenesis
- Enhances lipolysis elevates free fatty acids in the plasma compartment

Sweat glands:
- compensate for the elevated heat production during intense metabolic activity

Eye:
- pupil dilation
- lens adapts for distance vision

Question 13

Fill in.
Vascular smooth muscle in skeletal muscle contains both _____ and ____ receptors.

Answer 13

α1; β2

Question 14

Fill in.
Norepinephrine has a high affinity for ____ receptors, causing strong _________ . Epinephrine has high affinity for ______ receptors. this counters α1 mediated vasoconstriction.

Answer 14

α1; vasoconstriction; β2

Question 15

True or false.
Circulating catecholamines released from the adrenal medulla have a longer duration of effect and a more widespread distribution than neuronally released norepinephrine.

Answer 15

True

Question 16

How are fight, flight, freeze reactions inactivated

Answer 16

• Neural NE is removed from the synapse by re-uptake mechanisms on the postganglionic neuron. neural catecholamines are available for miliseconds
• circulating catecholamines are inactivated by catechol-O-methly transferase (COMT) in the liver. circulating catecholamines are available for 1-2 minutes.

Question 17

true or false.
Circulating catecholamines can stimulates cells not directly innervated by sympathetic fibers.

Answer 17

True

Question 18

Sympathetic fibers release what type of catecholamine?

Answer 18

norepinephrine

Question 19

adrenal medulla releases what type of catecholamine

Answer 19

Adrenal medulla releases primarily epinephrine.

Question 20

what is the overall effect of the parasympathetic division?

Answer 20

to conserve energy and regulate basal body functions

Question 21

Fill in.
Preganglionic neurons of the parasympathetic system arise from nuclei of the______ and the______ segments S2-S4 of the spinal cord.

Answer 21

brainstem; sacral

Question 22

preganglionic axons of parasympathetic are long or short?

Answer 22

long

Question 23

Where are postganglionic neurons of parasympathetic division located?

Answer 23

• close to or within the effector tissues

Question 24

True or false.
Postganglionic axons of parasympathetic division are long

Answer 24

false. they are short

Question 25

Fill in. The preganglionic neurons exit through cranial nerves _____ ; _____ ; _____ ; & ______

Answer 25

III ; VII ; IX ; X

Question 26

Fill in. The preganglionic axons from the sacral region of the spinal cord form the _______ and innervate the ______ of the pelvic cavity (eg, lower half of the large intestine and organs of the renal & reproductive systems).

Answer 26

pelvic nerves; viscera

Question 27

True or False. there is divergence in the parasympathetic system

Answer 27

False.

Question 28

True or false. The parasympathetic division of the ANS uses a ACh as pre- and post-ganglionic neurotransmitter

Answer 28

True

Question 29

Fill in. All preganglionic axons use acetylcholine (ACh) as their neurotransmitters. The cholinergic receptors on all autonomic ganglia is a _______ ______variety called the N2 receptor.

Answer 29

nicotinic ionotropic ;

Question 30

true or false. All of the parasympathetic postganglionic axons are also cholinergic.

Answer 30

True

Question 31

Fill in. the target effector organs of parasympathetic postganglionic axons express GPCRs known as _______ receptors

Answer 31

muscarinic

Question 32

N1 receptors are found at the _______; and is blocked by ______

Answer 32

NMJ (neuromuscular junction) ; curare

Question 33

N2 receptors are found in ________ ganglia; are blocked by _________

Answer 33

autonomic ; hexamethonium

Question 34

describe M1 MUSCARINIC receptors

Answer 34

effects mediated by Gq/IP3/DAG; expressed in cerebral cortex, hippocampus. Role in cognitive function and memory.

Question 35

describe Muscarinic-2 (M2) receptors

Answer 35

coupled to Gαi; located in atria, SA and AV nodes and myocardium; decreases heart rate and myocardial conduction velocity

Question 36

describe Muscarinic-3 (M3) receptors

Answer 36

effects mediated by Gq/IP3/DAG; smooth muscle of various organ systems, e.g. bronchi (constriction), GI tract (contraction), pupils (constriction),

Question 37

the only cholinergic receptor involved in a sympathetic process, is located where?

Answer 37

in sweat glands of the skin

Question 38

describe Muscarinic-4 and 5 receptors

Answer 38

M4; coupled to Gαi; M5; coupled to Gq - located primarily in the CNS, e.g., forebrain and substania nigra, respectively

Question 39

what are the parasympathetic effects on cardiac muscle, respiratory, GI, and eye

Answer 39

Cardiac: - heart rate decreases Respiratory: - bronchial constriction GI: - Salivary secretion is enhanced - Gastric motility and secretion are stimulated - Intestinal motility and secretion are stimulated - Both exocrine and endocrine secretion from the pancreas is promoted. Eye: - pupil constricts and the lens adapts for near vision

Question 40

True or false. both divisions of the ANS are tonically active in the pupil

Answer 40

True

Question 41

Fill in. The contains two groups of smooth muscles; a ________ group (constrictor muscles) & a _______ group (dilator muscles).

Answer 41

circular ; radial

Question 42

Fill in. Sympathetic fibers from the superior cervical ganglion innervate the _______ muscles. Parasympathetic fibers innervate the _______ muscles.

Answer 42

dilator; constrictor

Question 43

Fill in. __________ is a competitive antagonist for the muscarinic acetylcholine receptor types

Answer 43

atropine

Question 44

Fill in. Atropine _______ parasympathetic activation of the ______ smooth muscle. So all that is left is ________ activation of the radial muscle

Answer 44

blocks; circular ; sympathetic

Question 45

True or false. Control of the bladder and the timing of urination requires integration of both the parasympathetic and sympathetic division of the ANS

Answer 45

True.

Question 46

Fill in. the wall of the bladder is made up of ______ muscle. Also known as the detrusor muscle. The detrusor muscle expresses _____ adrenergic receptors and ________ receptors.

Answer 46

smooth; beta; muscarinic

Question 47

Fill in. filling of the bladder happens in it's ______ (relaxed/contracted) state. This occurs via ________ (sympathetic/parasympathetic) innervation

Answer 47

relaxed state; sympathetic

Question 48

Fill in. emptying of the bladder happens in its ________ (relaxed/contracted) state. This occurs via _________ (sympathetic/parasympathetic) innervation.

Answer 48

contracted ; parasympathetic

Question 49

Fill in. The internal sphincter is made of _______ muscle, while the external sphincter is made of _________ muscle and under voluntary control.

Answer 49

smooth ; skeletal

Question 50

Sympathetic activity of the bladder allows the bladder to relax and fill by activating ______ receptors, but maintains contraction of the internal sphincter by activating _______ receptors

Answer 50

beta 2 ; alpha 1

Question 51

parasympathetic activity causes the detrusor muscle to contract by activating _____ receptors, while the internal sphincter relaxes by activating _______ receptors

Answer 51

Muscarinic- M3 ; Muscarinic- M3

Question 52

Does the adrenal medulla receive parasympathetic innervation?

Answer 52

No

Question 53

what is sympathetic tone?

Answer 53

the baseline firing frequency in the innervating sympathetic axons

Question 54

Increasing the firing frequency __________ the sympathetic tone. while decreasing the firing frequency _____ the sympathetic tone

Answer 54

increases ; decreases