Administration of tryptophan-enriched diets to pregnant rats retards the development of the serotonergic system in their offspring

doi:10.1016/0165-3806(92)90059-6

Developmental Brain Research

Volume 68, Issue 2, 21 August 1992, Pages 175-181

https://doi.org/10.1016/0165-3806(92)90059-6 Get rights and content

Abstract

It is well established that an increased availability of tryptophan stimulates serotonin synthesis not only in the adult but also in the developing brain. In order to study the influence of a permanently increased supply of tryptophan on the developing central 5-HT-system, female rats were fed a tryptophan-enriched diet from mating throughout pregnancy and lactation. The effect of this dietary regime was assessed by measurements of neurochemical markers of 5-HT innervation in the developing brain of their offspring. A diminished content of 5-HT, a decreased activity of tryptophan hydroxylase and a reduction of crude synaptosomal high-affinity 5-HT uptake was found in the cortex and in the brain stem of 5 day old rat pups of mothers fed the tryptophan-enriched diet. The postnatal increase of all three markers of serotonergic innervation in the offspring of these mothers was retarded. Both the initial depletion and the delayed maturation of 5-HT content, of tryptophan hydroxylase activity and of synaptosomal serotonin uptake were more pronounced in the cortex than in the brain stem. Apparently, the increased dietary intake of tryptophan throughout pregnancy and lactation caused a delayed outgrowth of 5-HT axons and/or reduced collateral sprouting and synapse formation in the brain of the developing offspring.

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Research reportAdministration of tryptophan-enriched diets to pregnant rats retards the development of the serotonergic system in their offspring

Abstract

Life Sci.

Brain Res.

Brain Res.

Dev. Biol.

Psychoneuroendocrinol.

Progr. Brain Res.

Dev. Brain Res.

Pharmacol. Biochem. Behav.

Brain Res.

Brain Res. Bull.

Arch. Biochem. Biophys.

Neurosci. Lett.

Dev. Brain Res.

Brain Res.

Biochem. Pharmacol.

Dev. Brain Res.

5-Hydroxyindole metabolism in rat brain. A study of intermediate metabolism using the technique of tryptophan loading

J. Neurochem.

Plasma tryptophan and 5-HT metabolism in the CNS of the newborn rat

J. Neurochem.

Calcium-dependent, tetrodotoxin sensitive stimulation of cortical serotonin release after a tryptophan load

J. Neurochem.

Serotonin initiates and autoamplifies its own synthesis during mouse central nervous system development

Regional distribution and developmental change of Trp-oxylase activity in rat brain

J. Neurochem.

Role of precursor availability in control of monoamine biosynthesis in brain

Physiol. Rev.

Research report
Administration of tryptophan-enriched diets to pregnant rats retards the development of the serotonergic system in their offspring