Essential Pharmacology 1

Question 1

What is a receptor?

Answer 1

Responds to stimuli and generates a response

Question 2

How does the same receptor compare in different cells?

Answer 2

The same receptor may produce different responses in different cells

Question 3

How do receptor sub types compare in the same cell?

Answer 3

May provide different responses

Question 4

How to receptors allow specificity?

Answer 4

By only binding to certain substrate

Question 5

What things could a receptor alter as part of the response?

Answer 5

Membrane permeability

Metabolism

Secretory activity

Rate of proliferation or differentiation

Contractile activity

Question 6

What is the process of a receptor binding to a substrate and producing a response known as?

Answer 6

Signal transduction, or cell signalling

Question 7

What is signal transduction (cell signalling)?

Answer 7

Transmission of a molecular signal from a cells exterior to its interior

Question 8

What are the 3 main examples of receptors?

Answer 8

Intercellular receptor

Plasma membrane receptor

G protein coupled receptor

Question 9

What must lipids that bind to intracellular receptors be and why?

Answer 9

Lipophillic as they need to pass through the cell membrane

Question 10

What are two common intracellular receptor substances?

Answer 10

Steroid hormones

Nitric acid

Question 11

What happens when steroid hormones bind to intracellular receptors?

Answer 11

Binds to receptor

Often transcription factor, altering rate

Question 12

What does nitric acid do when it binds to an intracellular receptor?

Answer 12

Binds to soluble guonylyl cyclose

Generates cGMP as a second messenger which regulates cell activity

Question 13

What kind of receptor do molecules that cannot penetrate the cell membrane need to combine to?

Answer 13

Plasma membrane receptors

Question 14

What are the 4 types of plasma membrane receptors?

Answer 14

Ionotopic receptor (also acts as an ion channel)

Receptors that function as an enzyme

Receptors that directly alter enzyme activity, which is another protein

G protein coupled receptors

Question 15

How many transmembrane spanning segments do G proteins have?

Answer 15

7

Question 16

What happens when a substrate binds to a G protein?

Answer 16

1. Part of it dissociates and interacts with other proteins (channel or enzyme)
2. Causes the release of a second messenger within the cell

Question 17

What kind of things can G proteins do?

Answer 17

Form active transport

Channels

Protein synthesis

Enzymes

Secretion

Question 18

What are some examples of proteins coupled to G proteins?

Answer 18

Adrenylyl cyclase

Phospholipase C

Ion channels

Question 19

What does adrenylyl cyclase do?

Answer 19

Regulates cAMP (second messenger)

Regulates PKA

Question 20

What does phopholipase C do?

Answer 20

Produces diacylglycerol and inositol triphosphate

Activates PKC and releases Ca²⁺ from internal stores

Question 21

What do ion channels attatched to G proteins do?

Answer 21

Evoke slow IPSPs or slow EPSPs

Question 22

What often acts as a second messenger?

Answer 22

Ca²⁺

Question 23

Where are some sources of Ca²⁺?

Answer 23

Internal sources via IP₃⁺ or Ca²⁺ stimulated releases from endoplasmic reticulum

Outside the cell by using voltage or ligand gated Ca²⁺ channels

Inhibition of Ca²⁺ transport out of the cell

Question 24

What are some effects of Ca²⁺?

Answer 24

Directly effects proteins (like PKC)

Binds to calmodulin which activates protein target

Works via some other Ca²⁺ binding protein

Question 25

What is pharmacology?

Answer 25

Study of drug action