Summary
Serotonin (5-HT) receptors are modulated by L-valine (VAL). For further characterization of this effect a binding assay of [14C]-L-VAL has been developed. A brief description of the experimental conditions is given. Moreover, measurement of VAL-binding has been applied to human brain tissue either from controls or hepatic failure. A marked increase of VAL-binding sites with no change in affinity was noted in hepatic coma, while in patients treated with parenteral nutrition plus VAL no such change could be measured.
It is concluded that the beneficial therapeutic effects of VAL in hepatic encephalopathy are, at least in part, due to its modulating action on post-synaptic receptor membranes.
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Supported by the Jubiläumsfonds of the Oesterr. Nationalbank, Project 1965.
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Kienzl, E., Riederer, P., Jellinger, K. et al. [14C]-L-valine binding to membranes of the frontal cortex in hepatic encephalopathy. J. Neural Transmission 55, 309–315 (1982). https://doi.org/10.1007/BF01243452
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DOI: https://doi.org/10.1007/BF01243452