Cell Signaling

Question 1

3 ways drugs interfere with cell signaling

Answer 1

1. Interfere with release of cell signaling molecules
2. Mimic cell signaling molecules
3. Interfere with target of cell signaling molecules

Question 2

3 basic methods of cell signaling

Answer 2

1. Share information via gap junctions
2. Contact-dependent signaling
3. Signaling via secreted molecules

Question 3

Secreted molecules involved in signaling

Answer 3

1. Endocrine
2. Neuroendocrine
3. Paracrine
4. Neurotransmitter
5. Autocrine

Question 4

Targets for signaling

Answer 4

1. Cell-surface receptors
2. Intracellular receptors
3. Enzymes

Question 5

How many connexin molecules make one half pore?

Answer 5

6

Question 6

Gap junctions are made of?

Answer 6

Connexins

Question 7

Example of sharing info via gap junctions

Answer 7

Glucagon receptors and cAMP signal

Question 8

Example of contact-dependent signaling

Signal:

Receptor:

Answer 8

Leukocyte adhesion prior to transmigration in inflammation

Signal: glycoproteins on leukocyte

Receptor: adhesion protein on endothelial cell

Question 9

3 steps of contact-dependent signaling (using example of leukocyte and endothelial cells)

Answer 9

1. Leukocytes roll along endothelial cells (selectins)
2. Leukocyte adhere to endothelium (integrins)
3. Transmigration (leukocyte passes through gap between endothelial cells)

Question 10

Endocrine signaling molecule is transported via?

Answer 10

Circulation

Question 11

Neuroendocrine signaling molecule

Answer 11

Transported via circulation (similar to endocrine)

Signaling cell is a neuron

Question 12

Paracrine signaling

Answer 12

Signaling molecule diffuses to nearby cell (heterotypic)

Question 13

Neurotransmitter signaling

Answer 13

Signaling molecule is neuron, diffuses to nearby cell (similar to paracrine)

Question 14

Autocrine signaling

Answer 14

Signaling cell is target cell, diffuses to nearby cell (similar to paracrine)

Question 15

Anti-duretic hormone (ADH) is the same as?

Answer 15

Argenine-vasopressin (AVP)

Question 16

Example of endocrine signaling

Answer 16

ADH/AVP

Question 17

Example of paracrine signaling

Signals:

Answer 17

Histamine-induced vasodilation via nitric oxide

Signals: histamine and NO (both are paracrine)

Question 18

What is NO?

Answer 18

Gaseous signaling molecule which can diffuse through membrane to find its target

Question 19

NO half life

Answer 19

Very short (so it must be paracrine)

Question 20

Example of neuronal signaling

Answer 20

Acetylcholine in neuromuscular junction for voluntary muscle contraction

Question 21

Endocrine signal reaches ____ cells → ___ concentration is needed

Answer 21

Many cells → low concentration needed

Question 22

Synaptic signal reaches ___ cells → ___ concentration is needed

Answer 22

Only specific cells → high concentration needed

Question 23

Signaling molecules are very diverse. Name 8 kinds.

Answer 23

1. Proteins
2. Peptides
3. FA derivatives
4. AAs
5. Cholesterol derivatives
6. Small molecules
7. Dissolved gases
8. Ions

Question 24

Example of protein signaling molecules

Answer 24

Surface proteins on endothelial cells

Question 25

Example of peptide signaling molecules

Answer 25

Vasopressin

Question 26

Example of FA derivative signaling molecules

Answer 26

Prostaglandins

Question 27

Example of AA signaling molecules

Answer 27

Glutamate

Question 28

Example of cholesterol derivative signaling molecules

Answer 28

Aldosterone

Question 29

Examples of small molecule acting as signaling molecules

Answer 29

1. Acetylcholine | 2. Epinephrine

Question 30

Example of dissolved gases as signaling molecules

Answer 30

Nitric oxide

Question 31

Example of ions as signaling molecules

Answer 31

Ca2+, K+

Question 32

Solubility defines?

Answer 32

1. Body space in which drug is diluted | 2. Location of receptors reached

Question 33

Water soluble signaling molecules are predisposed to reach?

Answer 33

Extracellular receptors

Question 34

Example of water soluble signaling molecule

Answer 34

Epinephrine

Question 35

Lipid soluble signaling molecules travel how?

Answer 35

1. Bound to proteins through blood stream | 2. Free hormones

Question 36

Lipid soluble signaling molecules are predisposed to reach?

Answer 36

Intracellular receptors

Question 37

Example of lipid soluble signaling molecule

Answer 37

Aldosterone

Question 38

Signaling molecules for intracellular receptors and intracellular enzymes must be?

Answer 38

Small and hydrophobic

Question 39

Example of signaling molecule for cell-surface receptor

Answer 39

ADH/AVP

Question 40

Example of signaling molecule for intracellular receptor

Answer 40

Aldosterone for control of [plasma K+]

Question 41

Aldosterone increase?

Answer 41

K+ excretion | Na+ and water retention

Question 42

How does aldosterone affect [plasma K+]?

Answer 42

1. Targets kidney collecting duct 2. Activates genes coding for Na+/K+ ATPase → K+ is excreted, Na+ and water is retained

Question 43

Example of signaling molecule for intracellular enzyme

Answer 43

Vasodilation via NO