Ch. 15.6- Comparison of Neurotransmitters

Question 1

What are cholinergic neurotransmitters?

Answer 1

Neurons the make and release ACh.

Question 2

Cholinergic receptors

Answer 2

Receptors the bind ACh.

There are only two types of theses. They are nicotinic and muscarinic.

Question 3

Which are cholinergic neurons?

Answer 3

All sympathetic and parasympathetic preganglionic neurons.
All parasympathetic preganglionic neurons.
Sympathetic ganglionic neurons that innervate sweat glands of the skin.

Question 4

Adrenergic Neurons

Answer 4

Neurons that make and secrete norepinephrine.

Question 5

Adrenergic Receptors

Answer 5

Neurons that bind norepinephrine or epinephrine.

These are decided into alpha and beta types.

Question 6

Nicotinic receptors

Answer 6

Found on the cell bodies and dendrites of all ganglionic neurons and on adrenal medulla cells.

Question 7

What happened when nicotinic receptors are stimulated?

Answer 7

Na+ enters the the cell and K+ leaves the cell.

Question 8

Muscarinic Receptor locations

Answer 8

All target organs associated with the parasympathetic nervous system and a few sympathetic (sweat glands of skin and blood vessels in skeletal muscle) target cells.

Question 9

What kind of message system do muscarinic receptors use?

Answer 9

Second messenger systems.

Question 10

Ligands

Answer 10

Signaling molecules (hormones and neurotransmitters) that specifically bind to receptors in the plasma membrane.

Question 11

Biogenic amines

Answer 11

Also called monoamines

Ligands that bind to adrenergic receptors in neurons.

Question 12

Catecholamines

Answer 12

Category of biogenic amines.

These induce dopamine, epinephrine, and norepinephrine

Question 13

What types of adrenergic receptors are there?

Answer 13

Alpha 1, Alpha 2, Beta 1, Beta 2, Beta 3

Question 14

What are alpha 1 receptors responsible for?

Answer 14

Most common adrenergic receptor of the sympathetic division of the autonomic nervous system.
Found in the plasma membranes of most smooth muscles cells.
They stimulate smooth muscle contraction.
Organs stimulated: Blood vessels of skin, GI, and kidneys, arrector pili muscles, uterus, ureters, internal urethra sphincter, and dilatory pupillae muscles of the eye.
This means dilation of blood vessels, and contraction of other muscles.

Question 15

What are alpha 2 receptors responsible for?

Answer 15

Located throughout the CNS and decrease norepinephrine release.
Also in the pancreases to inhibit insulin secretion.
Also found in the GI sphincter which causes the sphincter to close.
Stimulation of these causes sedation and analgesia.

Question 16

Beta 1 adrenergic receptors

Answer 16

Primarily stimulatory effects.
Found in the heart where they increase heart rate and force of contraction.
Found in kidneys where they stimulate secretion of renin-which causes an increase in blood pressure.

Question 17

Beta 2 adrenergic receptors

Answer 17

Primarily inhibitory effects.
Present in coronary arteries and smooth muscle vessels of the liver.
Stimulation of these causes smooth muscle relaxation.
This also causes bronchodilation and relaxation of uterine tract and GI smooth muscle.

Question 18

Beta 3 adrenergic receptors

Answer 18

Excitatory of inhibitory.
Found in adipose connective tissue where they stimulate lipolyisis (break down of triglycerides into fuel molecules)
Also cause smooth muscle relaxation in urinary bladder.