The summaries are free for public
use. The Chronic Liver Disease
Foundation will continue to add and
archive summaries of articles deemed
relevant to CLDF by the Board of
Trustees and its Advisors.
Abstract Details
Effects of hyperammonemia on brain energy metabolism: controversial findings in vivo and in vitro
Schousboe A1, Waagepetersen HS, Leke R, Bak LK. Metab Brain Dis. 2014 Mar 1. [Epub ahead of print]
Author information
1Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen Ø, Denmark.
Abstract
The literature related to the effects of elevated plasma ammonia levels on brain energy metabolism is abundant, but heterogeneous in terms of the conclusions. Thus, some studies claim that ammonia has a direct, inhibitory effect on energy metabolism whereas others find no such correlation. In this review, we discuss both recent and older literature related to this controversial topic. We find that it has been consistently reported that hepatic encephalopathy and concomitant hyperammonemia lead to reduced cerebral oxygen consumption. However, this may not be directly linked to an effect of ammonia but related to the fact that hepatic encephalopathy is always associated with reduced brain activity, a condition clearly characterized by a decreased CMRO2. Whether this may be related to changes in GABAergic function remains to be elucidated.