Tertiary and quaternary local anesthetics protect CNS white matter from anoxic injury at concentrations that do not block excitability

Tertiary and quaternary local anesthetics protect CNS white matter from anoxic injury at... Abstract 1. Anoxic injury in CNS white matter was studied using the in vitro rat optic nerve preparation. Optic nerves were subjected to 60 min of anoxia, and functional recovery was assessed using the area under the compound action potential (CAP). In normal cerebrospinal fluid, CAP area recovered to 33.5 +/- 9.3% (SD) of control. 2. Lidocaine and procaine (0.1 or 1.0 mM), applied beginning 1 h before anoxia, significantly improved postanoxic recovery of CAP area. However, both agents also depressed the preanoxic CAP. Procaine generally allowed greater recovery with less depression compared with lidocaine. 3. The quaternary derivatives QX-314 (0.1-1.0 mM) and QX-222 (0.3-3.0 mM) resulted in more complete recovery of the CAP area from anoxia, with less depression of preanoxic excitability, compared with the tertiary compounds. At 0.3 mM, QX-314 reduced the preanoxic CAP very little (to 94.4 +/- 14% of control CAP area), yet allowed the postanoxic CAP area to recover to 99.6 +/- 19%. 4. We conclude that quaternary local anesthetics are more effective at protecting CNS white matter tracts from anoxia than tertiary compounds and that these agents can result in markedly improved recovery even at concentrations that do not block conduction. Moreover, given the relative specificity of QX-314 for noninactivating Na+ channels, we hypothesize that this channel subtype plays an important role in mediating anoxic injury in central myelinated axons. Copyright © 1992 the American Physiological Society http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Neurophysiology The American Physiological Society

Tertiary and quaternary local anesthetics protect CNS white matter from anoxic injury at concentrations that do not block excitability

Journal of Neurophysiology, Volume 67 (1): 236 – Jan 1, 1992

Loading next page...
 
/lp/the-american-physiological-society/tertiary-and-quaternary-local-anesthetics-protect-cns-white-matter-CimZXqJsWO
Publisher
The American Physiological Society
Copyright
Copyright © 1992 the American Physiological Society
ISSN
0022-3077
eISSN
1522-1598
Publisher site
See Article on Publisher Site

Abstract

Abstract 1. Anoxic injury in CNS white matter was studied using the in vitro rat optic nerve preparation. Optic nerves were subjected to 60 min of anoxia, and functional recovery was assessed using the area under the compound action potential (CAP). In normal cerebrospinal fluid, CAP area recovered to 33.5 +/- 9.3% (SD) of control. 2. Lidocaine and procaine (0.1 or 1.0 mM), applied beginning 1 h before anoxia, significantly improved postanoxic recovery of CAP area. However, both agents also depressed the preanoxic CAP. Procaine generally allowed greater recovery with less depression compared with lidocaine. 3. The quaternary derivatives QX-314 (0.1-1.0 mM) and QX-222 (0.3-3.0 mM) resulted in more complete recovery of the CAP area from anoxia, with less depression of preanoxic excitability, compared with the tertiary compounds. At 0.3 mM, QX-314 reduced the preanoxic CAP very little (to 94.4 +/- 14% of control CAP area), yet allowed the postanoxic CAP area to recover to 99.6 +/- 19%. 4. We conclude that quaternary local anesthetics are more effective at protecting CNS white matter tracts from anoxia than tertiary compounds and that these agents can result in markedly improved recovery even at concentrations that do not block conduction. Moreover, given the relative specificity of QX-314 for noninactivating Na+ channels, we hypothesize that this channel subtype plays an important role in mediating anoxic injury in central myelinated axons. Copyright © 1992 the American Physiological Society

Journal

Journal of NeurophysiologyThe American Physiological Society

Published: Jan 1, 1992

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off