Total and free plasma tryptophan levels in patients with affective disorders: effects of a peripheral decarboxylase inhibitor.

  title={Total and free plasma tryptophan levels in patients with affective disorders: effects of a peripheral decarboxylase inhibitor.},
  author={Paul E. Garfinkel and Jerry J. Warsh and Harvey C. Stancer and David Sibony},
  journal={Archives of general psychiatry},
  volume={33 12},
Previous reports of decreased cerebrospinal fluid tryptophan levels and decreased free plasma tryptophan levels, as well as a reduction in the volume of distribution of tryptophan, suggest that alterations in the disposition of plasma tryptophan may occur in depressives. We examined the disposition of plasma tryptophan in ten normal controls and ten depressed patients. These measures were made on two drug-free baseline days and on two days when the subjects had been receiving the peripheral… 

Tryptophan and depressive illness

Although exogenously administered oestrogens do not have any therapeutic efficacy in relieving mild residual depressive symptoms of lithium treated patients, they increased the levels of plasma free tryptophan, which reduced the levels in depressed patients.

Kinetics of l-tryptophan in depressive patients: A possible correlation between the plasma concentrations of l-tryptophan and some psychiatric rating scales

No kinetic differences could be demonstrated in the depressive patients, making differences in body compartments or flux of l-tryptophan unlikely to be of pathogenic importance to depression.

Tryptophan tolerance and metabolism in endogenous depression

It is concluded that the absorption, the plasma clearance, and the degradation to kynurenine of loading doses of l-tryptophan are normal in depressed patients.

Plasma tryptophan binding to albumin in unipolar depressives

No differences in the equilibrium constants were detected between patients and controls but a small increase in the albumin concentration was noted in the depressives and it was agreed that this rise would be inadequate to lead to a significant effect on free tryptophan levels.

Blood tryptophan metabolism in chronic schizophrenics.

Concomitant measures of blood indole metabolism were conducted in 33 chronic schizophrenics who showed significantly elevated mean platelet serotonin (5-HT) values and lower platelet monoamine

Diurnal rhythm in the plasma level of total and free tryptophan and cortisol in rabbits

  • L. HusseinH. Goedde
  • Biology
    Research in experimental medicine. Zeitschrift fur die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie
  • 1979
The results suggest that tryptophan in plasma is poorly transported in the brains of rabbits treated with chlorpromazine, and that treatment with haloperidol or chlor Promazine may lead to a reduced tryptophile flux into the kynurenine pathway.

Tryptophan, Cortisol and Puerperal Mood

Seasonal variation occurred in the incidence of 'blues' and in cortisol and free tryptophan levels, and Puerperally-depressed mood was correlated with high cortisol at 38 weeks irrespective of season.



l-Tryptophan in affective disorders: Indoleamine changes and differential clinical effects

Marked changes in cerebro-spinal fluid, platelet and urinary levels of serotonin and 5-hydroxyindoleacetic acid in patients with bipolar affective disorder suggest that the low response rate of severely depressed patients is probably not attributable to impaired l-tryptophan metabolism during depression.

Dietary Carbohydrate Increases Brain Tryptophan and Decreases Free Plasma Tryptophan

Car carbohydrate ingestion, which raises plasma tryptophan while depressing the concentrations of its competitors, increases the amount of tryPTophan in the brain and accelerates synthesis of serotonin in young rats; on the other hand, protein consumption causes proportionately greater increases in the other neutral amino acids than in plasma trypsophan, and thus fails to elevate brain tryptophon or serotonin.

Free Tryptophan in Plasma and Brain Tryptophan Metabolism

Often when 5HT turnover in the rat brain increases—as indicated by higher concentrations of its metabolite 5-hydroxyindoleacetic acid (5HIAA)—there is a corresponding increase in brain tryptophan.

Cerebrospinal Fluid Levels of MHPG in Affective Disorders

The catecholamine hypothesis of affective disorders, which associates decreased functional catechlamines with depression, has been tested by measurement of noradrenaline in plasma or urine or the NA metabolites, normetanephrine and VMA in urine, and results have led to conflicting results.

Tryptophan metabolism in depressive illness

It is concluded that the apparent volume of distribution of tryptophan is reduced in depressive individuals, consistent with other findings of increased protein-binding of plasma tryPTophan and reduced CSF tryptophile levels in depressive patients.

Brain Serotonin Content: Physiological Dependence on Plasma Tryptophan Levels

Brain serotonin cocentrations at 1 p.m. were significantly elevated 1 hour after rats received a dose of L-tryptophan and plasma and brain tryptophan levels were elevated 10 to 60 minutes after the injection, but they never exceeded the concentrationis that occur nocturnally in untreated aninmals as result of their normal 24-hour rhythms.

Changes on recovery in the concentrations of tryptophan and the biogenic amine metabolites in the cerebrospinal fluid of patients with affective illness

Findings are against the amine hypothesis which postulated in depression a lowered concentration of transmitter amine at synaptic junction and there was a high correlation between HVA and HVA in the same CSF.

Psychomotor activity and cerebrospinal fluid amine metabolites in affective illness.

CSF levels of 5-hydroxyindoleacetic acid and homovanillic acid were significantly higher after simulated mania or exercise alone than in the same patients after bed rest, and both metabolites were higher in severe mania than in hypomania.