LAD blockage affects which ion pump? - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 07-27-2012
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 1,039
Threads: 189
Thanked 557 Times in 318 Posts
Reputation: 567
Question LAD blockage affects which ion pump?

A 56-year-old man complains of chest pain associated with shortness of breath and fatigue. A coronary angiogram indicates 85% blockage of the left anterior descending coronary artery. Which ion pump is most directly affected by the myocardial ischemia?

a) Calcium
b) Bicarbonate
c) Potassium
d) Proton
e) Sodium
Reply With Quote Quick reply to this message
The above post was thanked by:
curiousmind (07-28-2012)



  #2  
Old 07-27-2012
USMLE Forums Addict
 
Steps History: 1+CK+CS
Posts: 196
Threads: 9
Thanked 97 Times in 64 Posts
Reputation: 107
Default

E?? 10char
Reply With Quote Quick reply to this message
  #3  
Old 07-27-2012
USMLE Forums Guru
 
Steps History: 1 + CK
Posts: 454
Threads: 20
Thanked 338 Times in 160 Posts
Reputation: 358
Default

C: only ATP dependent channel in heart muscle...
__________________
262/261/PASS 1st attempt/238- USCE 1.5 mo (Uni hospital). YOG -2013; home country resident for 6 mo
Reply With Quote Quick reply to this message
  #4  
Old 07-27-2012
USMLE Forums Addict
 
Steps History: 1 + CS
Posts: 142
Threads: 33
Thanked 97 Times in 28 Posts
Reputation: 107
Default

E.

Ischemia= No O2. No ATP synthesis.

Directly effects Na/K ATPase.
Water follows the Na and cell swells up. Halts protein synthesis.

Becomes irreversible when Ca influx comes in to release Caspace.
Reply With Quote Quick reply to this message
  #5  
Old 07-27-2012
Anders's Avatar
USMLE Forums Veteran
 
Steps History: 1+CK+CS
Posts: 289
Threads: 7
Thanked 129 Times in 102 Posts
Reputation: 139
Default

Quote:
Originally Posted by ashoka1202 View Post
E.

Ischemia= No O2. No ATP synthesis.

Directly effects Na/K ATPase.
Water follows the Na and cell swells up. Halts protein synthesis.

Becomes irreversible when Ca influx comes in to release Caspace.
E
Reply With Quote Quick reply to this message
  #6  
Old 07-28-2012
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 1,039
Threads: 189
Thanked 557 Times in 318 Posts
Reputation: 567
Correct Answer correct answer :)

The answer is C) proton pump -> mitochondria -> ATP production

The question was: Which ion pump is most directly affected by the myocardial ischemia?
Reduced blood flow to the heart slows mitochondrial electron transport and the proton pumps that are coupled to it, because oxygen is the terminal electron acceptor of the electron transport chain. This leads to a decrease in the supply of adenosine triphosphate in the myocardium.


Na/K ATPase would be affected indirectly (no fuel for the engine)
Reply With Quote Quick reply to this message
The above post was thanked by:
alice (10-16-2012), curiousmind (07-28-2012), Janakpriya (02-17-2013), succinylcholine (02-17-2013)
  #7  
Old 02-17-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 17
Threads: 0
Thanked 1 Time in 1 Post
Reputation: 11
Post

plz confrim it C or D
Reply With Quote Quick reply to this message



Reply

Tags
Cardiovascular-, Molecular-Biology-, Physiology-, Step-1-Questions

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to pump up scores on uworld? mbbs2010 USMLE Step 1 Forum 3 12-17-2011 07:58 AM
What thyroid disease affects this pregnant woman aksyonez USMLE Step 2 CK Forum 7 11-16-2011 09:01 AM
Reverse neuromuscular blockage docnok USMLE Step 1 Forum 1 09-26-2011 08:55 AM
Reversing Neuromuscular Blockage! plasticsurgeon USMLE Step 1 Forum 11 09-13-2011 12:29 PM
What affects your CS performance in CIS subdivisions? DrSeddik USMLE Step 2 CS Communication Skills 1 04-25-2011 05:54 PM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)