Region-selective decreases in densities of [3H]tryptamine binding sites in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy.
The distribution of [3H]tryptamine binding sites, in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy (HE) and an equal number of age-matched control subjects free from hepatic, neurological, or psychiatric disorder, was investigated. Scatchard analysis demonstrated a heterogeneous distribution for this binding site, with the highest density being observed in hippocampus >> frontal cortex = caudate nucleus > temporal cortex = cerebellum. When comparing [3H]tryptamine binding site densities in control brain tissue with that in brain tissue from patients with HE, significant decreases in densities were observed in the frontal cortex (by 56%, p < 0.001), hippocampus (by 43%, p < 0.001), and caudate nucleus (by 41%, p < 0.01) of the HE group. Binding site affinities were within normal limits. The findings of decreased densities of [3H]tryptamine binding sites taken in conjunction with previous reports of increased CSF and brain tryptamine concentrations in HE suggest a pathogenic role for this neuroactive amine in HE resulting from chronic liver failure.
Mousseau
D D
DD
Neuroscience Research Unit, André-Viallet Clinical Research Center, Hôpital St.-Luc (University of Montreal), Québec, Canada.
Layrargues
G P
GP
Butterworth
R F
RF
D001344:Autopsy; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D006501:Hepatic Encephalopathy / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008103:Liver Cirrhosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D014018:Tissue Distribution; D014316:Tritium; D014363:Tryptamines / Q000378:metabolism*
D014363:Tryptamines; D014316:Tritium; C030820:tryptamine