Cerebral blood flow and metabolism in chronically hyperammonemic rats: Effect of an acute ammonia challenge

Cerebral blood flow and metabolism in chronically hyperammonemic rats: Effect of an acute ammonia... The effects of chronic hyperammonemia on cerebral metabolism were studied in rats four and eight weeks after the construction of a portacaval shunt. Compared to sham‐operated controls, shunted animals had increased arterial concentrations of ammonia and glutamine and decreased glutamate. Cerebral blood flow, measured by xenon 133 washout in animals lightly anesthetized with nitrous oxide, increased from a control of 91 ± 5 (mean ± SEM) to 139 ± 20 ml per 100 gm tissue per minute after shunting for eight weeks; however, the cerebral metabolic rate for oxygen was not different from control four or eight weeks after the shunting procedure. Following intraperitoneal administration of a small ammonium acetate load (2.6 mmol/kg), eight‐week portacaval animals consistently underwent a fall in cerebral blood flow and cerebral oxygen consumption and developed high‐voltage slow waves in the electroencephalogram. Glutamine was produced by the brains of all groups of animals; the cerebral metabolic rate for glutamine was greater than control in eight‐week portacaval rats, the only animals to show a net uptake of ammonia, along with nonspecific effects of chronic portal‐systemic shunting, may lead to uncoupling of cerebral blood flow and oxidative metabolism. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Annals of Neurology Wiley

Cerebral blood flow and metabolism in chronically hyperammonemic rats: Effect of an acute ammonia challenge

Loading next page...
 
/lp/wiley/cerebral-blood-flow-and-metabolism-in-chronically-hyperammonemic-rats-UhrNQafZUQ
Publisher
Wiley
Copyright
Copyright © 1978 the American Neurological Association
ISSN
0364-5134
eISSN
1531-8249
DOI
10.1002/ana.410030409
Publisher site
See Article on Publisher Site

Abstract

The effects of chronic hyperammonemia on cerebral metabolism were studied in rats four and eight weeks after the construction of a portacaval shunt. Compared to sham‐operated controls, shunted animals had increased arterial concentrations of ammonia and glutamine and decreased glutamate. Cerebral blood flow, measured by xenon 133 washout in animals lightly anesthetized with nitrous oxide, increased from a control of 91 ± 5 (mean ± SEM) to 139 ± 20 ml per 100 gm tissue per minute after shunting for eight weeks; however, the cerebral metabolic rate for oxygen was not different from control four or eight weeks after the shunting procedure. Following intraperitoneal administration of a small ammonium acetate load (2.6 mmol/kg), eight‐week portacaval animals consistently underwent a fall in cerebral blood flow and cerebral oxygen consumption and developed high‐voltage slow waves in the electroencephalogram. Glutamine was produced by the brains of all groups of animals; the cerebral metabolic rate for glutamine was greater than control in eight‐week portacaval rats, the only animals to show a net uptake of ammonia, along with nonspecific effects of chronic portal‐systemic shunting, may lead to uncoupling of cerebral blood flow and oxidative metabolism.

Journal

Annals of NeurologyWiley

Published: Apr 1, 1978

References

  • Glycogen, ammonia and related metabolites in the brain during seizures evoked by methionine sulphoximine
    Folbergrová, Folbergrová; Passonneau, Passonneau; Lowry, Lowry
  • The glutamate and glutamine content of rat brain after portocaval anastomosis
    Williams, Williams; Kyu, Kyu; Fenton, Fenton

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