Neurohumoral Control of the Heart & Circulation - Quiz 10

Question 1

Which Sympathetic Nerve Receptor predominantly causes Vasoconstriction?

Answer 1

Alpha-1 Receptor

Question 2

Which Sympathetic Nerve Receptor predominantly causes increased Contractility?

Answer 2

Beta-1 Receptor

Question 3

Which Sympathetic Nerve Receptor inhibits neurotransmitter release?

Answer 3

Alpha-2

Question 4

What does stimulation of the Beta-2 Receptor cause?

Answer 4

Bronchodilation

Vasodilation

Uterine Relaxation

Glycogenolysis

Question 5

What are the precursors to Epinephrine?

Answer 5

Tyrosine > Dopamine > Norepi > Epi

Question 6

What is Dromotropy?

Answer 6

Conduction velocity of AV Node

Question 7

What is Lusitropy?

Answer 7

Relaxation of Myocardium

Question 8

What is the Major differnces bt/ the Sympathetic & Parasympathetic system?

Answer 8

Sympathetic: Excitatory Cardiac Effects - Innervates entire heart

Parasympathetic: Vagus Nerve - Inhibitory Cardiac Effects - Innervates Atria & SA/AV Nodes

Question 9

Which Catecholamine does the Adrenal Gland mostly release w/ Sympathetic Stimulation?

Answer 9

Epinephrine - 80%

Norepinephrine - 20%

Question 10

What is the “Second Messenger” of the Sympathetic Stimulation of heart muscle cell?

Answer 10

Cyclic AMP - allows greater Ca++ influx

Question 11

What happens intracellularly when catecholamines bind to the Beta-Adrenergic Receptor?

Answer 11

Activates Adenylyl Cyclase - Converts ATP to cAMP

Question 12

What happens intracellularly when catecholamines bind to the Alpha-1 Receptor?

Answer 12

Activates Phospholipase to increase Ca++ into vessel smooth muscle causing vasoconstriction

Question 13

What is Renin and how does it work?

Answer 13

Enzyme secreted by Kidney

Angiotensinogen > Angiotensin I > (ACE) > Angiotensin II > (Adrenal Cortex) > Aldosterone

Sodium & Fluid Retention = ↑BP & ↑Blood Volume

Question 14

What is Vasopressin?

Answer 14

ADH released by Posterior Pituitary - causes vasocontriction & increases blood volume by renal fluid reabsorption

Question 15

What does the Atrial Natriuretic Peptide do?

Answer 15

Decreases SVR & CVP by decreasing release of Renin

Increases Diuresis

Decreases Blood Volume

Question 16

What are the Indirect effects of Hypoxia on the Circulatory System?

Answer 16

Sympathetic Stimulation to ↑HR, ↑Contractility, & ↑SVR

Question 17

What is the Baroreceptor Reflex?

Answer 17

Receptors located in Cartoid Sinus & Aortic Arch

Senses blood pressure & adjusts HR, Contractility, & SVR accordingly.

Question 18

What surgery does Baroreceptor Reflex activation frequently cause hemodynamic changes?

Answer 18

Carotid Endarterectomy

Question 19

What does the Bainbridge Reflex do?

Answer 19

Increased Blood Volume = Increased HR

Slow Baseline = Increase HR w/ fluid

Fast Baseline = Decreased HR w/ fluid

Question 20

Where are the Atrial Stretch Receptors Located?

Answer 20

Vena Cava - Right Atrial Junction

Pulmonary Vein - Left Atrial Junction

Question 21

What are the effects of Atrial Stretch Reflex that is not part of the Bainbridge Reflex?

Answer 21

Increase Urine Output

Decrease BP & Blood Volume

Question 22

What is the Bezold-Jarisch Reflex?

Answer 22

Happens when there is a Strong Contraction of underfilled ventricle

causes Bradycrdia & Hypotension

Question 23

What is the CNS Ischemic Response?

Answer 23

When Low BP causes low O2 & high CO2 in the Medullary Vasomotor Center resulting in increased HR, Contractility, and MAP

Question 24

What is the Cushing Response?

Answer 24

Type of CNS Ischemic Response

Increased ICP d/t increased BP until blow flows are normal in the brain

Question 25

What is Cushing's Triad?

Answer 25

Increased ICP Hypertension Bradycardia

Question 26

What is the Diving Reflex?

Answer 26

Activates when the face feels cold water and decreases HR & increases Vasoconstriction

Question 27

Where are the Peripheral Chemoreceptors located?

Answer 27

Aortic & Cortoid Bodies

Question 28

What do the Peripheral Chemoreceptors do?

Answer 28

**Respiration Regulation** and **Increases SVR & MAP** Decreased PaO2 & Increased PCO2 excites vasomotor center d/t **decreased BP** Activated when MAP \< 80 mmHg

Question 29

What stimulates the Atrial Natriuretic Peptide (ANP)?

Answer 29

Atrial Distention Sympathethic Stimulation Angiotensin II Endothelin

Question 30

What are the Direct effects of Hypoxia on the Circulatory System?

Answer 30

Profound Hypoxia causes ↓HR & ↓Contractility

Question 31

What is the Indirect effect of Hypercarbia?

Answer 31

Sympathetic stimulation causing ↑HR, ↑Contractility, & ↑SVR

Question 32

What is the Direct effect of Hypercarbia?

Answer 32

↓Contractility

Question 33

What is the "Fight or Flight" Response?

Answer 33

Mass discharge of Sympathetic Nervous System ↑BP ↑Blood Glucose ↑Strength & ↑Focus ↑Coagulation ↑Metabolism

Question 34

What are the 2 Types of Acetylcholine Receptors?

Answer 34

Muscarinic Receptor & Nicotinic Receptor - neuromuscular junction

Question 35

How does Neostigmine work?

Answer 35

Anti-Cholinersterase @ Nicotinic Receptor - Reverse muscle relaxant @Muscarinic - Bradycardia, Bronchospams, Salivation - Give Glycopyrrolate (Robinul)

Question 36

Which part of the Brainstem is the Vasomotor Center located?

Answer 36

Medulla

Question 37

Which neurotransmitter is released between the Pre-Ganglionic & Post-Ganglionic _Sympathetic_ fibers?

Answer 37

Acetylcholine

Question 38

Which neurotransmitter is released between the Post-Ganglionic _Sympathetic_ fibers & Target Site?

Answer 38

Norepinephrine

Question 39

Which neurotransmitter is released between the Pre-Ganglionic Sympathetic Fiber & Adrenal Medulla?

Answer 39

Acetylcholine

Question 40

Which Autonomic Nervous System innervates Blood vessels except for capillaries?

Answer 40

Sympathetic Nervous System