2 - Barker Problem Sets

Question 1

Some diruetics increase K+ excr while others decr K+ excr. List a combination of two diuretics that would minimize K= secr.

Answer 1

Any two where one is a K+ sparing diuretics. HCTZ and triameterne is the most common combination.

CHTZ will promote K+ loss, whereas triamterene will reduce K+ wasting.

Question 2

Of the following diuretics which one would most likely lead to the most pronounced diuretic effect?

torsemide
acetazolamide
triamterene

Answer 2

torsemid is a loop diuretic.
diuretics that work in the thick ascending limb of the loop of Henle are the most effect d/t effects on Na/K/Cl transporter

Question 3

Describe the effects of ethancrynic acid on the excretion of the following ions.
Na / K / Cl / Bicarb / Mg / Ca

Answer 3

incr
incr
incr
no change 
incr
incr

Question 4

explain how chlorthalidone causes diuresis

Answer 4

thiazide-like diuretic

blocks the Na/Cl symporter in the DCT reducing Na reabs. Increase natriuresis –> diuresis

Question 5

Define azotemia.

Answer 5

biochemical abnormality in which an elevation of BUN and Cr levels, which is largely related to decr GFR

Question 6

Define ureamia.

Answer 6

An excess of urea and other nitrogenous waste in the blood.

Question 7

Define proteinuria.

Answer 7

a condition in which urine contains an abnormal amt of protein

Question 8

What modifications to the structure of ACh will descrease the susceptibility of the molecule to hydrolysis by AChE. What effects does each have on selecitivty for cholinergic receptors?

Answer 8

beta methyl –> more muscarinic

replace ester w carbamyl –nothing

Question 9

Which portion of a molecule will interact with the anionic and esteratic sites of AChE?

Answer 9

anionc: charged amine, aromatic ring
esteratic: ester

Question 10

What type of chemical interaction is important for binding to the anionic site of AChE?

Answer 10

pi cation

Question 11

What is the therapuetic advantage of a selective beta2-adrenergic receptor agonist?

Answer 11

if would have fewer effects on the heart

Question 12

ACh and physostigmine both modify the same AA on the esteratic site of AChE, yet physostigmine inhibits the action of the synzyme. explain how physostigmine inhibitis AChE.

Answer 12

Physostigmine modifies the serine in the active site and the carbamyl group on the serine is hydrolyzed slowly.

Question 13

What characteristics of a structure would make it a more potent muscarinic receptor agonist?

Answer 13

resemble muscarine
five member ring with positive charge up

(???)

Question 14

What drug OD might be responsible for causing N/D, foaming at mouth, constricted pupiils, bradycardia, and delirium? The drug was a medication for Alzheimer’s disease.

Answer 14

AChE inhibitor
Any of the Alzheimer’s drug discussed besides Naminda

Aricept

Question 15

What is the most appropriate drug or drugs for the treatment of the grandfather’s overdose?

Answer 15

atropine = anti-cholinergic drug

no reason for pralidoxine bd not reversible

Question 16

You have cloned the gene for an enzyme from the esterase family. The enzyme’s turnover for various substrates is:
ACh 2x10^8
succinylcholine 1x10^9
butrylylcholine 4x10^8

Is the enzyme more likely to be AChE or plasma cholinesterase

Answer 16

AChE is very specific for ACh

–> this is plasma cholinesterase. breaks down things other than ACh and better than ACh

Question 17

Which effects of ephedrine would be blocks by phentolamine but not propranolol?

Answer 17

epinephrine activates alpha1, alpha2, beta 1, beta 2 –> decr BP a little, incr HR

phentolamine is an alpha1, alpha2 antag –> would block alpha1 effects/vasoconstriction.

propranolol is a non-selective beta antagonist. would block effects on heart, kidney, and bronchioles.

Question 18

Resperine effectively decreases blood pressure, yet htere is little or no reflex tachycardia assocaited with reserpine use. Why?

Answer 18

baroreceptors are short-term regulation.

reserpine has a slow onset of action. the baroreceptor reflex doesn’t come into play.

Question 19

Phentolamine only partially blocks the symptoms of pheochromocytoma. Why? What other drugs might more completely alleviate the symptoms associated with pheochromocytoma?

Answer 19

pheochromacytoma is an adrenal turmor. elevates epinephrine.

phentolamine blocks alpha1 and alpha 2 effects. beta effects still occur.

could add a beta blocker or use a mixed adrenergic like carvedilol.

Question 20

From the structure of betaxolol, predict the activity (receptor selecitivty and is it an ag or antag). It is used in the treatment of glaucoma. Does this make sense.

Answer 20

amine with bulky head group–> beta selectivity
non-carbon in alkyl chain–> beta blocker.

a beta blocker will decr production of aq humor by the ciliary epithelium.

Question 21

What would a dose-response curve for albuterol acivation of beta2 receptors in bronchial smooth muscle would look in the prescence of nadolol or a low dose of atenolol?

Answer 21

nadolol: non-selective beta-blocker: will shift right
atenolol: beta1 specific blocker, will not shift D-R curve