Sympathetic Nervous System (Corbett) - 11/2/16

Question 1

Major effects of adrenergic receptors

Answer 1

Question 2

What two organs are part of the sympathetic nervous system but are innervated by cholinergic fibers?

Answer 2

Adrenal medulla

Sweat Glands

Question 3

Nicotinic ACh receptors are ________ ______ channels.

Two subtypes

Answer 3

ligand-gated Na+/K+

N_N (found in autonomic ganglia, adrenal medulla)

N_M (found in neuromuscular junction of skeletal muscle)

Question 4

Muscarinic ACh receptors are ___________.

5 subtypes

Answer 4

G-protein-coupled receptors that usually act through 2nd messengers

M_1-5 found in heart, smooth muscle, brain, exocrine glands, and sweat glands (cholinergic sympathetic)

Question 5

G-protein-linked 2nd messengers

1. Sympathetic receptors: alpha 1
2. G-protein class: “qisses”
3. Location
4. Major functions:

Answer 5

1. Alpha-1 adrenergic receptors
2. Gq –> inc. intracellular Ca2+
3. Post-synaptic membranes
4. Functions:
   
   1. Vasoconstriction → Inc. vascular smooth muscle contraction
      
      1. Inc. BP leading to decreased
   2. Mydriasis → Inc. pupillary dilator muscle contraction
      
      1. Inc. Intraocular pressure (watch out for glaucoma!)
   3. Urinary retention → Inc. intestinal and bladder sphincter muscle contraction
   4. MINIMAL EFFECTS ON HEART (mostly beta 1)

Question 6

G-protein-linked 2nd messengers

1. Sympathetic receptors: alpha 2
2. G-protein class: “qisses”
3. Location
4. Major functions:

Answer 6

1. alpha-2 adrenergic receptors
2. i
3. pre-synaptic membrane
4. Functions:
   
   1. dec. sympathetic outflow (dec. cAMP → inhibit NE and ACh release)
   2. dec. insulin release
   3. dec. lipolysis
   4. dec. aqueous humor production → dec. intraocular pressure
   5. inc. platelet aggregation

Question 7

G-protein-linked 2nd messengers

1. Sympathetic receptors: beta 1
2. G-protein class: “qisses”
3. Location
4. Major functions:

Answer 7

1. beta-1 adrenergic receptor
2. s
3. post-synaptic
4. functions
   
   1. Inc. HR
   2. Inc. contractility
   3. Inc. Renin release
   4. Inc. lipolysis

Question 8

G-protein-linked 2nd messengers

1. Sympathetic receptors: beta 2
2. G-protein class: “qisses”
3. Location
4. Major functions:

Answer 8

1. Beta-2 adrenergic receptors
2. s
3. Presynaptic (create positive feedback loop - work in opp way of what alpha-2 receptors do)
   
   1. Vasodilation
   2. Bronchodilation
   3. Inc. lipolysis
   4. Inc. insulin release
   5. Inc. aqueous humor production
   6. Dec. uterine tone (tocolysis) → relaxation
   7. Dec. ciliary muscle relaxation