1. Low-grade brain edema in HE
Low-grade brain edema in HE. Ammonia induces astrocyte swelling, which is, in part, counteracted by osmolyte depletion but can be aggravated by a set of precipitating factors.
Low-grade brain edema in HE. Ammonia induces astrocyte swelling, which is, in part, counteracted by osmolyte depletion but can be aggravated by a set of precipitating factors. Astrocyte swelling involves activation of the N-methyl-D-aspartate receptor and the generation of reactive nitrogen oxide species, which again cause astrocyte swelling. The autoamplificatory loop produces signals that change the astrocyte function at multiple levels, including covalent modifications of proteins and ribonucleic acid, resulting in impaired glioneuronal communication, synaptic plasticity, and brain networks, which finally account for the symptoms of HE. Adapted with permission from Haussinger et al,18 with partial revision, and from BMJ Publishing Group Ltd. PBR indicates peripheral benzodiazepine receptor; RNI, reactive nitrogen intermediates; ROI, reactive oxygen intermediates.
L.J. Zhang et al. AJNR Am J Neuroradiol 2013;34:
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