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Flashcards in kinetics/dynamics Deck (20):
1

phase 1 reactions

oxidation, reduction, hydrolysis

2

phase 2 reaction

conjugation

3

Hepatic Microsomal Enzymes Location

-primarily in the hepatic smooth endoplasmic reticulum
-also in the kidneys, GI tract, and adrenal cortex

4

CYP450

-hepatic microsomal enzymes
-mixed function oxidase system

5

microsomal enzymes (what type of metabolism)

oxidation, reduction, conjugation

6

microsomal activity is lowest in...

neonates, premature infants

7

Non-microsomal Enzymes (what type of metabolism)

conjugation, hydrolysis

8

Non-microsomal enzymes (location)

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

9

first order kinetics

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

10

zero order kinetics

-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)

11

94% steady state

4 half-times

12

how many half-lives eliminate 96% on drug

5 half lives

13

context sensitive half time

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

14

bioavailability affected by...

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

15

Voltage Gated Ion Channels

-open and close depending on cell membrane voltage
-ex) local anesthetics

16

Ligand-gates Ion Channel

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

17

Transmembrane Receptors

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

18

enzymes

ex) phosphodiesterase inhibitors, viagra, milrinone

19

receptor down regulation

-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)

20

receptor up regulation

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