Ammonia toxicity: from head to toe?
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Ammonia is diffused and transported across all plasma membranes. This entails that hyperammonemia leads to an increase in ammonia in all organs and tissues. It is known that the toxic ramifications of ammonia primarily touch the brain and cause neurological impairment. However, the deleterious effects of ammonia are not specific to the brain, as the direct effect of increased ammonia (change in pH, membrane potential, metabolism) can occur in any type of cell. Therefore, in the setting of chronic liver disease where multi-organ dysfunction is common, the role of ammonia, only as neurotoxin, is challenged. This review provides insights and evidence that increased ammonia can disturb many organ and cell types and hence lead to dysfunction.
KeywordsAmmonia Brain Muscle Hepatic encephalopathy Toxicity Liver
Compliance with ethical standards
The authors have no conflicts to disclose. SD supported in part by NIH grants: RO1 DK 83414, R21 AA 022742, UO1 AA021893 and P50 AA024333 8236.
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