Biomaterial Database

Neuroactive amino acids in hepatic encephalopathy. 1996

R F Butterworth

Neuroscience Research Unit, Hôpital Saint-Luc (University of Montreal, Qué., Canada.

There is abundant evidence to suggest that alterations of excitatory and inhibitory amino acids play a significant role in the pathogenesis of hepatic encephalopathy (HE) in both acute and chronic liver diseases. Brain glutamate concentrations are reduced in patients who died in hepatic coma as well as in experimental HE, astrocytic reuptake of glutamate is compromised in liver failure and postsynaptic glutamate receptors (both NMDA and non-NMDA subclasses) are concomitantly reduced in density. Recent studies in experimental acute liver failure suggest reduced capacity of the astrocytic glutamate transporter in this condition. Together, this data suggests that neuron-astrocytic trafficking of glutamate is impared in HE. Other significant alterations of neuroactive amino acids in HE include a loss of taurine from brain cells to extracellular space, a phenomenon which could relate both to HE and to brain edema in acute liver failure. Increased concentrations of benzodiazepine-like compounds have been reported in human and experimental HE. Clinical trials with the benzodiazepine antagonist flumazenil reveal a beneficial effect in some patients with HE; the mechanism responsible for this effect, however, remains to be determined.

UI	MeSH Term	Description	Entries
D006501	Hepatic Encephalopathy	A syndrome characterized by central nervous system dysfunction in association with LIVER FAILURE, including portal-systemic shunts. Clinical features include lethargy and CONFUSION (frequently progressing to COMA); ASTERIXIS; NYSTAGMUS, PATHOLOGIC; brisk oculovestibular reflexes; decorticate and decerebrate posturing; MUSCLE SPASTICITY; and bilateral extensor plantar reflexes (see REFLEX, BABINSKI). ELECTROENCEPHALOGRAPHY may demonstrate triphasic waves. (From Adams et al., Principles of Neurology, 6th ed, pp1117-20; Plum & Posner, Diagnosis of Stupor and Coma, 3rd ed, p222-5)	Encephalopathy, Hepatic,Portosystemic Encephalopathy,Encephalopathy, Hepatocerebral,Encephalopathy, Portal-Systemic,Encephalopathy, Portosystemic,Fulminant Hepatic Failure with Cerebral Edema,Hepatic Coma,Hepatic Stupor,Hepatocerebral Encephalopathy,Portal-Systemic Encephalopathy,Coma, Hepatic,Comas, Hepatic,Encephalopathies, Hepatic,Encephalopathies, Hepatocerebral,Encephalopathies, Portal-Systemic,Encephalopathies, Portosystemic,Encephalopathy, Portal Systemic,Hepatic Comas,Hepatic Encephalopathies,Hepatic Stupors,Hepatocerebral Encephalopathies,Portal Systemic Encephalopathy,Portal-Systemic Encephalopathies,Portosystemic Encephalopathies,Stupor, Hepatic,Stupors, Hepatic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D001569	Benzodiazepines	A group of two-ring heterocyclic compounds consisting of a benzene ring fused to a diazepine ring.	Benzodiazepine,Benzodiazepine Compounds
D017397	Prefrontal Cortex	The rostral part of the frontal lobe, bounded by the inferior precentral fissure in humans, which receives projection fibers from the MEDIODORSAL NUCLEUS OF THE THALAMUS. The prefrontal cortex receives afferent fibers from numerous structures of the DIENCEPHALON; MESENCEPHALON; and LIMBIC SYSTEM as well as cortical afferents of visual, auditory, and somatic origin.	Anterior Prefrontal Cortex,Brodmann Area 10,Brodmann Area 11,Brodmann Area 12,Brodmann Area 47,Brodmann's Area 10,Brodmann's Area 11,Brodmann's Area 12,Brodmann's Area 47,Pars Orbitalis,Frontal Sulcus,Gyrus Frontalis Inferior,Gyrus Frontalis Superior,Gyrus Orbitalis,Gyrus Rectus,Inferior Frontal Gyrus,Lateral Orbitofrontal Cortex,Marginal Gyrus,Medial Frontal Gyrus,Olfactory Sulci,Orbital Area,Orbital Cortex,Orbital Gyri,Orbitofrontal Cortex,Orbitofrontal Gyri,Orbitofrontal Gyrus,Orbitofrontal Region,Rectal Gyrus,Rectus Gyrus,Straight Gyrus,Subcallosal Area,Superior Frontal Convolution,Superior Frontal Gyrus,Ventral Medial Prefrontal Cortex,Ventromedial Prefrontal Cortex,Anterior Prefrontal Cortices,Area 10, Brodmann,Area 10, Brodmann's,Area 11, Brodmann,Area 11, Brodmann's,Area 12, Brodmann,Area 12, Brodmann's,Area 47, Brodmann,Area 47, Brodmann's,Area, Orbital,Area, Subcallosal,Brodmanns Area 10,Brodmanns Area 11,Brodmanns Area 12,Brodmanns Area 47,Convolution, Superior Frontal,Convolutions, Superior Frontal,Cortex, Anterior Prefrontal,Cortex, Lateral Orbitofrontal,Cortex, Orbital,Cortex, Orbitofrontal,Cortex, Prefrontal,Cortex, Ventromedial Prefrontal,Cortices, Ventromedial Prefrontal,Frontal Convolution, Superior,Frontal Gyrus, Inferior,Frontal Gyrus, Medial,Frontal Gyrus, Superior,Frontalis Superior, Gyrus,Gyrus, Inferior Frontal,Gyrus, Marginal,Gyrus, Medial Frontal,Gyrus, Orbital,Gyrus, Orbitofrontal,Gyrus, Rectal,Gyrus, Rectus,Gyrus, Straight,Gyrus, Superior Frontal,Inferior, Gyrus Frontalis,Lateral Orbitofrontal Cortices,Olfactory Sulcus,Orbital Areas,Orbital Cortices,Orbital Gyrus,Orbitalis, Pars,Orbitofrontal Cortex, Lateral,Orbitofrontal Cortices,Orbitofrontal Cortices, Lateral,Orbitofrontal Regions,Prefrontal Cortex, Anterior,Prefrontal Cortex, Ventromedial,Prefrontal Cortices, Anterior,Region, Orbitofrontal,Subcallosal Areas,Sulcus, Frontal,Superior Frontal Convolutions,Superior, Gyrus Frontalis,Ventromedial Prefrontal Cortices
D018698	Glutamic Acid	A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.	Aluminum L-Glutamate,Glutamate,Potassium Glutamate,D-Glutamate,Glutamic Acid, (D)-Isomer,L-Glutamate,L-Glutamic Acid,Aluminum L Glutamate,D Glutamate,Glutamate, Potassium,L Glutamate,L Glutamic Acid,L-Glutamate, Aluminum