Autonomic Nervous System

Question 1

Mydriasis

Answer 1

Pupillary Dilation

Question 2

Sympathetic Nervous System includes increase in which of the following?

Answer 2

Increase in:
-Blood flow to the skeletal muscles
-Increase in HR
-Increase in BP
-Increase in blood sugar level
-Mydriasis (pupillary dilation: scared by a bear response, wide eyed)

Question 3

Parasympathetic Nervous System involves which physiological responses?

Answer 3

-Conservation and restoration of body energy
-Decrease in heart rate
-Increase in activity of GI tract
-Myosis (pupillary constriction)

Question 4

Vagomoty

Answer 4

A Surgical operation in which one or more branches of the vagus nerve are cut, typically to reduce the rate of gastric secretion (Eg. in treating peptic ulcers)

Question 5

Preganglionic neuron releases [ ] as neurotransmitter, which binds to cholinergic nicotinic receptors

Answer 5

Acetylcholine

Question 6

Pheochromocytoma

Answer 6

-Most common tumor of the adrenal medulla
-Derived from chromaffin cells
-Secrete epinephrine, norepinephrine, and dopamine
-Symptoms: occurs in “spells”-relapse and remit: Elevated BP, Headache, Excessive sweating, palpitations (tachycardia), pallor.
-Labs: Elevated catecholamines and their metabolites, metanephrine
-Treatment: Surgery
-Pre-op: Phenoxybenzamine + beta-blocker

Question 7

Organophosphate poisoning

Answer 7

Acetylcholinesterase enzyme inhibition
Symptoms:
-Muscarinic: diarrhea, urination, miosis, bronchospasm, bradycardia, emesis, lacrimation, sweating, salivation
-Nicotinic: neuromuscular blockage
-CNS effects: respiratory depression, lethargy, seizures, coma
-Treatment: Atropine + Pralidoxime

Question 8

Nicotinic Receptors

Answer 8

Ion channel linked (Nm, Nn): ligand gated sodium/potassium channels

Question 9

Muscarinic Receptors

Answer 9

G-protein linked
M1, M2, M3, M4, M5

Question 10

Gq-protein linked receptors and action

Answer 10

M1, M3, M5
Increases: IP3 (Inositol triphosphate), DAG (Diacylglycerol), Ca2+

Question 11

Gi protein linked receptors and action

Answer 11

M2, M4
Decreases: cAMP

Question 12

M1 Receptor

Answer 12

Nerve endings: Gq-coupled

Question 13

M2 Receptor

Answer 13

Heart, some nerve endings, Gi-coupled (muscle, inhibitory action, activates K+ channels)

Question 14

M3 Receptor

Answer 14

Effector cells: smooth muscle, glands, endothelium, Gq-coupled, increased IP3, DAG cascade

Question 15

Nn receptor

Answer 15

ANS ganglia, Na+, K+ ion channel, Depolarizes evokes action potential

Question 16

Nn receptor

Answer 16

Neuromuscular end plate, Na+, K+ ion channel
-Depolarizes, evokes action potential