Chapter 18

Question 1

Define pharmacokinetics

Answer 1

Study of the time course of drug and metabolite level in different body fluids and tissues including absorption, distribution, metabolism and elimination

Question 2

Define pharmacodynamics

Answer 2

The study of relationship between drug effects and its concentration

Question 3

What is the main mechanism of phase 1 metabolism?

Answer 3

Mainly occur through CYP-450 system in the liver, and can be oxidative, reductive or hydrolytic processes.

Question 4

What is the main mechanism of phase 1 metabolism?

Answer 4

Mainly occur through CYP-450 system in the liver, and can be oxidative, reductive or hydrolytic processes.

Question 5

After CYP-450 metabolism, what is the main fuction of the metabolites?

Answer 5

Usually they create metabolites which remain active, or phase 1 activated a prodrug (such as cyclophosphamide)

Question 6

What is the MOA for alkylating agents

Answer 6

Formation of covalent binding of the alkyl group to macromolecules in the cell such as DNA. Pending on the type of alkylating agent it will form a mono or bifunctional adduct that generate intra or interstrand cross-links resulting in cell death.

Question 7

Name 4 mechanisms of resistance commonly seen with alkylating agents?

Answer 7

1. Decreased transport over the cell membrane
2. Increased intracellular level of thiol (glutathione) concentration with result in reduced likleyhood of adduct forming with DNA
3. Increased enzymatic detoxification of reactive mediators
4. Alteration in DNA-repair enzymes

Question 8

Are alkylating agent cell-cycle specific?

Answer 8

No