Module I - Receptors and Genetics

Question 1

3 Signal Transduction Mechanisms of Agonist Receptors

Answer 1

1) enzyme activation/inhibition
2) ion channel modulation
3) DNA transcription

Question 2

Binding of an agonist to a receptor ion channel
Binding of a ligand to a receptor tyrosine kinase
Binding of steroid hormones to intracellular receptors

Answer 2

Major modes of signal transduction and intracellular signaling

Question 3

Relaying of a message from the outside of the cell to the inside.

Answer 3

Signal Transduction

Question 4

(e.g., GABAA receptor or nicotinic acetylcholine receptor) leads to opening of a transmembrane pore that permits movement of ions across the plasma membrane. This leads to a change in membrane potential that results in the physiologic response (e.g., change in the firing characteristics of a neuron or muscle contraction).

Answer 4

Binding of an agonist to a receptor ion channel

Question 5

Results in receptor dimerization and phosphorylation of the intracellular kinase domain. The activated (phosphorylated) kinase domain is then specifically recognized by proteins such as Src and phospholipase C that in turn activate a network of downstream effectors

Answer 5

Binding of a ligand to a receptor tyrosine kinase receptor

Question 6

Results in the dissociation of the G protein into the membrane α subunit and the soluble βγ dimer. The α subunit then interacts with downstream effectors such as adenylyl cyclase, which converts ATP into cAMP (a second messenger) that then modifies a number of effector proteins. The βγ dimer can also exert direct cellular effects by modulating activity of a number of ion channels

Answer 6

Binding of a ligand to a seven transmembrane domain G protein-coupled receptor (GPCR)

Question 7

The 3 primary processes of pharmacokinetics

Answer 7

1) Absorption
2) Distribution
3) Elimination

Question 8

The relationship between dose and effect can be separated into two components that have to do with dose-concentration and concentration-effect

Answer 8

Pharmacokinectics & Pharmacodynamics

Question 9

A drug or endogenous chemical that binds to a receptor, resulting in the opposite action of an agonist. Using the two-state model, they appear to bind preferentially to the inactivated receptor.

Answer 9

Inverse Agonist

Question 10

These types of ligands may have a theoretic advantage over antagonists in situations in which a disease state is partly due to an up-regulation∗ of receptor activity.

Answer 10

Inverse Agonist

Question 11

Full Agonists have a full effect.
Partial Agonist have a partial
Antagonists produce no effect, or maintains the basal state
Inverse Agonists produce the opposite of the agonistic effect.

Answer 11

Agonist vs Antagonist Relationship

Question 12

This type of ligand produces the desired effect but the magnitude of the effect is incomplete or less.

Answer 12

Partial agonist

Question 13

In order for the body to excrete a drug, it must be biotransformed to…

Answer 13

Hydrophilic

Question 14

Most drugs are __________ b/c they need to be absorbed, pass through membranes, and react with proteins/receptors

Answer 14

lipophilic

Question 15

Molecules that are neutral in charge

No net charge associated with them

Answer 15

Non-Polar

Question 16

molecules that do not have a net charge, however certain regions of the molecule have a partial negative and positive charge.
These types of molecules are water soluble.

Answer 16

Polar