Muscle Physiology Case Histories - Case 7

Prior to intubation for a surgical procedure, the anesthesiologist administered a single dose of the neuromuscular blocking agent, succinylcholine, to a 23-year-old male to provide muscular relaxation during surgery and to facilitate the insertion of the endotracheal tube. Following this, the inhalation anesthetic was administered and the surgical procedure completed.

1. Beginning with depolarization at the neuromuscular junction, describe the normal sequence of events which lead to muscle contraction.

2. What prevents acetylcholine (ACh) from accumulating in the neuromuscular junction and causing a sustained contraction in a normal individual?

3. Succinylcholine acts as a depolarizing agent that prevents repolarization of the nerve. Therefore, no further ACh is released until the drug is cleared. Name another site within the neuromuscular junction that might be affected to prevent muscle contraction. (Hint: curare acts by this mechanism.)

Please enter your e-mail address:

If you would like your answers submitted to your instructor, please provide his/her e-mail address (or you must re-enter your e-mail address here for this form to work):

Please enter your full name:

A copy of your answers will also be submitted to your e-mail address so you may print the information.

Table of Contents

feedback form | permissions | international | locate your campus rep | request a review copy

digital solutions | publish with us | customer service | mhhe home

Copyright ©2001 The McGraw-Hill Companies.
Any use is subject to the Terms of Use and Privacy Policy.
McGraw-Hill Higher Education is one of the many fine businesses of the The McGraw-Hill Companies.