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. 1985 Jul;85(3):591–598. doi: 10.1111/j.1476-5381.1985.tb10553.x

Evidence that the accumulation of 5-hydroxytryptamine in the liver but not in the brain may cause the hypoglycaemia induced by 5-hydroxytryptophan.

Y Endo
PMCID: PMC1916514  PMID: 3875380

Abstract

Experiments were undertaken to determine whether the site of the hypoglycaemic action of 5-hydroxytryptophan (5-HTP), a direct precursor of 5-hydroxytryptamine (5-HT), was in the central nervous system or in the liver. The fall in blood glucose followed the rapid increase in the amount of 5-HT both in the brain and liver after 5-HTP injection into pargyline-treated and non-treated mice. Carbidopa, an inhibitor of peripheral aromatic amino acid decarboxylase, prevented the elevation of 5-HT levels in the liver of both pargyline-treated and non-treated mice. In contrast, carbidopa did not prevent but rather enhanced the elevation of 5-HT levels in the brain of both groups of mice. Corresponding to the prevention of 5-HT elevation in the liver, the fall in blood glucose was prevented by carbidopa. These results support the idea that the accumulation of 5-HT in the liver but not in the brain causes the hypoglycaemia induced by 5-HTP.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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