Week # 15 Renal, Hepatic, and biochemistry

Question 1

What are the 3 mechanisms for the regulation of acid-base balance?

Answer 1

the buffer system, the respiratory system, and the renal system

(all three are considered buffering systems)

Question 2

What are the predominant buffers of the renal system?

Answer 2

phosphate and ammonia

Question 3

To maintain normal pH, the kidneys must perform what 2 physiological functions?

Answer 3

1 - reabsorb all the filtered bicarbonate

2 - excrete the daily hydrogen ion load

Question 4

Adding acid load to the body fluids results in consumption of _______ and the formation of _______ _____?

Answer 4

consumption of bicarbonate

formation of carbonic acid

Question 5

Which buffering system can permanently eliminate excess hydrongen ions?

Answer 5

the renal system

Question 6

Which buffering system can restore bicarbonate ions to the blood?

Answer 6

the renal system

Question 7

What are 3 ways to lose hydrogen ions?

Answer 7

loss from vomiting

loss from H+ in urine

hyperventilation
(the slides said hypoventilation, but that doesn’t make sense)

Question 8

What are 3 ways to gain hydrogen ions?

Answer 8

loss of bicarb in the GI tract

loss of bicarb in the kidneys

from protein breakdown

Question 9

What is a buffer?

Answer 9

any substance that can reversibly bind hydrogen ions

Question 10

H2O + _____ _____ _____ + H+

Answer 10

H2O + CO2 H2CO3 HCO3 + H+

Question 11

What is the enzyme responsible for the reaction of CO2 + H2O H2CO3?

Answer 11

carbonic anhydrase

Question 12

What percent of cardiac output goes to the kidneys?

Answer 12

25%

Question 13

Approximately how many milliliters of urine is produced each minute?

Answer 13

1 - 2 mL / minute

Question 14

What is the path of renal blood flow, starting with the afferent arteriole?

Answer 14

afferent arteriole –> glomerulus –> efferent arteriole –> peritubular capillaries –> renal vein

Question 15

What is the main function of the proximal tubule?

Answer 15

reabsorption of the bulk of filtered fluid

Question 16

What is the main function of the loop of Henle?

Answer 16

establishes and maintains an osmotic gradient in the medulla of the kidney

Question 17

What is the main function of the distal tubule and collecting ducts?

Answer 17

final adjustments on urine pH, osmolality, and ionic composition

Question 18

What hormone is responsible for the reabsorption of water?

Answer 18

antidiuretic hormone (ADH)

Question 19

What hormone is responsible for reabsorption of sodium and secretion of potassium?

Answer 19

aldosterone

Question 20

Oxidation, reduction, methylation, and hydrolysis are what type of reactions?

Answer 20

Phase I reactions

Question 21

Phase I reactions are known as _______ or _______ reactions.

Answer 21

catabolic or breakdown

Question 22

Glucuronidation, glutathione conjugation, sulfation, and acetylation are what type of reactions?

Answer 22

Phase II reactions

Question 23

Phase II reactions are usually known as ________ reactions.

Answer 23

conjugate

Question 24

The ultimate goal of both Phase I and Phase II reactions is to make a more _____-______ product.

Answer 24

water-soluble

for elimination purposes

Question 25

What is responsible for the process of Phase I reactions?

Answer 25

cytochrome p-450

Question 26

What are some examples of drugs metabolized by Phase II reactions?

Answer 26

morphine, acetaminophen, digoxin, sulfonamides, dopamine, and epinephrine

Question 27

Drugs with a high hepatic extraction ratio depends on what for metabolism?

Answer 27

blood flow

Question 28

Drugs with a low extraction ratio depend on what for metabolism?

Answer 28

enzyme activity and protein binding

Question 29

The local anesthetics, procaine, chloroprocaine, and tetracaine are all esters. How are they metabolized?

Answer 29

by pseudocholinesterase | a plasma cholinesterase

Question 30

How are amide local anesthetics metabolized?

Answer 30

by liver metabolism

Question 31

What is the most important plasma protein for binding of drugs?

Answer 31

albumin

Question 32

How are benzodiazepines metabolized?

Answer 32

in the liver by hepatic microsomal oxidation and glucuronide conjugation (so, by both Phase I and Phase II reactions!)

Question 33

With the exception of remifentanil, how are opioids eliminated?

Answer 33

by hepatic metabolism

Question 34

How is remifentanil metabolized?

Answer 34

by ubiquitous esterases in the plasma

Question 35

What are the methods of metabolism for propofol?

Answer 35

hepatic glucuronate and sulfate conjugation | Phase II reactions

Question 36

What are the methods of metabolism for etomidate?

Answer 36

ester hydrolysis (major) and N-dealkylation (minor)

Question 37

What is the method of metabolism for ketamine?

Answer 37

N-demethylation ketamine --> (N-demethylation) --> norketamine

Question 38

Are the hepatic microsomes which contain the cytochrome p-450 enzymes responsible for metabolizing anesthetic gases?

Answer 38

yes, yes they are

Question 39

How is succinylcholine metabolized?

Answer 39

by pseudocholinesterase | a plasma cholinesterase. because succinylcholine is an ester

Question 40

How is cisatracurium eliminated?

Answer 40

hofman elimination

Question 41

How is vecuronium eliminated?

Answer 41

primarily by biliary excretion

Question 42

How is rocuronium eliminated?

Answer 42

primarily by biliary excretion secondarily by renal and hepatic metabolism

Question 43

Hepatic blood flow is _________ with general anesthesia and regional anesthesia.

Answer 43

decreased

Question 44

Decreased hepatic blood flow will ______ metabolism of other drugs, such as phenytoin, coumadin, ketamine, etc.

Answer 44

inhibit

Question 45

What are 4 important functions of the kidneys?

Answer 45

1. regulation of ECF/BP 2. regulation of ionic composition 3. electrolyte balance (Na, K, Ca, Mg, Cl) 4. acid-base balance (H+ and HCO3)

Question 46

What is the major energy macromolecule within the body?

Answer 46

adenosine triphosphate (ATP)

Question 47

What is the net ATP production of anaerobic respiration?

Answer 47

2 ATP

Question 48

What is the net ATP production of aerobic respiration?

Answer 48

34 - 38 ATP

Question 49

During anaerobic metabolism, what does the end product of glycolysis (pyruvate) get converted to?

Answer 49

lactic acid

Question 50

How much ATP is produced specifically within the Krebs Cycle?

Answer 50

none | ATP is formed during glycolysis and oxidative phosphorylation within the electron transport chain

Question 51

How many trips around the Krebs Cycle do you get with one glucose molecule?

Answer 51

2 | because the glucose molecule gets split into 2 parts during glycolysis

Question 52

ATP production by ATP synthase is made possible by what is known as an _________ _______.

Answer 52

electrochemical gradient (the electron transport chain pumps hydrogen ions across the inner matrix of the mitrochondria, creating an area of higher concentration within the cell matrix. since there is more hydrogen there, it wants to get back to the inside of the cell, but the only way it can is to do work and make some ATP!)

Question 53

What are the two enzymes responsible for transporting hydrogen ions to the electron transport chain, which can then be used to create an electrochemical gradient?

Answer 53

NADH and FADH (technically it's NAD and FAD. the H on both of them stands for hydrogen. so, when they are transporting the hydrogen, you tack on the H. pretty cool, huh?)

Question 54

Is hemoglobin a quaternary protein structure?

Answer 54

yup, sure is. | meaning, it has a heme group for each of its four polypeptides

Question 55

Hemoglobin has _______ _______ with oxygen. Meaning, that there is a structural change with each oxygen bound, making it easier for more oxygen to bind to the hemoglobin.

Answer 55

cooperative binding (this is also the reason that most hemes will completely fill with oxygen prior to unoxygenated hemoglobin begin to bind with oxygen)