kinetics/dynamics

Question 1

phase 1 reactions

Answer 1

oxidation, reduction, hydrolysis

Question 2

phase 2 reaction

Answer 2

conjugation

Question 3

Hepatic Microsomal Enzymes Location

Answer 3

• primarily in the hepatic smooth endoplasmic reticulum

- also in the kidneys, GI tract, and adrenal cortex

Question 4

CYP450

Answer 4

• hepatic microsomal enzymes

- mixed function oxidase system

Question 5

microsomal enzymes (what type of metabolism)

Answer 5

oxidation, reduction, conjugation

Question 6

microsomal activity is lowest in…

Answer 6

neonates, premature infants

Question 7

Non-microsomal Enzymes (what type of metabolism)

Answer 7

conjugation, hydrolysis

Question 8

Non-microsomal enzymes (location)

Answer 8

• primarily in liver

- also in plasma, renal tissue, muscles, and GI tracts

Question 9

first order kinetics

Answer 9

-constant fraction cleared per unit time (cleared at rate proportional to the amount of drug in plasma)

Question 10

zero order kinetics

Answer 10

• constant amount per unit time (drugs exceed capacity of the body by first order kinetics, instead cleared by amount per unit time)
• ASA, phenytoin, ETOH (until concentration falls below zero first order capacity again)

Question 11

94% steady state

Answer 11

4 half-times

Question 12

how many half-lives eliminate 96% on drug

Answer 12

5 half lives

Question 13

context sensitive half time

Answer 13

time necessary for drug plasma concentration to decrease by 50% after discontinuation of drug infusion

Question 14

bioavailability affected by…

Answer 14

-incomplete absorption
-fist pass hepatic effect
-pulmonary uptake
-uptake to other tissues
(NOT protein binding)

Question 15

Voltage Gated Ion Channels

Answer 15

• open and close depending on cell membrane voltage

- ex) local anesthetics

Question 16

Ligand-gates Ion Channel

Answer 16

• function as receptor ion channel complexes where the ion channel is part of the complex transmembrane protein
• ex) GABA, benzo, barb

Question 17

Transmembrane Receptors

Answer 17

• interact selectively with extracellular compounds to initiate a cascade of biochemical events that lead to the response
• ex) beta adrenergic receptor, opioid

Question 18

enzymes

Answer 18

ex) phosphodiesterase inhibitors, viagra, milrinone

Question 19

receptor down regulation

Answer 19

• a decrease in the number of receptors occurs in response to excessive ligand
• ex) decrease in beta receptors in response to pheocromocytoma (less response to vasopressor)

Question 20

receptor up regulation

Answer 20

• an increase in the number of receptors in response to a decrease in receptor stimulation
• ex) chronic beta antagonism (stop beta blocker- HTN, tachy)