Short- and long-term lithium administration: effects on the brain's serotonergic biosynthetic systems.
Short-term treatment with lithium chloride stimulates the uptake of tryptophan and its conversion to serotonin by striate synaptosomes. Preincubation of striate synaptosomes with L-tryptophan and in vivo administration of L-tryptophan appear to act in a similar manner. Midbrain tryptophan hydroxylase activity is reduced in temporal continuity with the lithium-induced activation of tryptophan uptake and conversion. By 10 days, conversion of tryptophan to serotonin in nerve endings becomes a joint function of the maintained increased uptake of tryptophan and a decreased level of tryptophan hydroxylase activity in nerve endings. The occurrence of this delayed alteration corresponds in time to the previously described axoplasmic flow rate for tryptophan hydroxylase.
D000818:Animals; D002247:Carbon Isotopes; D002421:Caudate Nucleus / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D007700:Kinetics; D008094:Lithium / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D008636:Mesencephalon / Q000201:enzymology / Q000378:metabolism*; D009411:Nerve Endings / Q000378:metabolism; D051381:Rats; D012701:Serotonin / Q000096:biosynthesis*; D013574:Synaptosomes / Q000378:metabolism; D013997:Time Factors; D014364:Tryptophan / Q000378:metabolism; D014365:Tryptophan Hydroxylase / Q000378:metabolism
D002247:Carbon Isotopes; D012701:Serotonin; D014364:Tryptophan; D008094:Lithium; D014365:Tryptophan Hydroxylase