A preliminary study of tryptophan depletion on tics, obsessive-compulsive symptoms, and mood in Tourette's syndrome

Rasmusson, Ann M.; Anderson, George M.; Lynch, Kimberly A.; McSwiggan-Hardin, Maureen; Scahill, Lawrence; Mazure, Carolyn M.; Goodman, Wayne K.; Price, Lawrence H.; Cohen, Donald J.; Leckman, James F.

doi:10.1016/s0006-3223(96)00380-0

Cited by 13 publications

(3 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has to be considered that brain tryptophan concentrations do not depend only on plasma tryptophan levels, but also on the concentrations of the large amino acids. Animal experimental studies 19 and studies in humans 53,54 indicate that the increase of total and free plasma tryptophan levels after administration of a tryptophan-supplemented amino acid mixture is not accompanied by an increase of brain tryptophan or brain 5-HT levels. The plasma ratio of tryptophan and large amino acids after ingestion of a tryptophan-supplemented amino acid beverage, comparable to the one we used, suggests that some decrease occurred in tryptophan availability at the carrier, and also possibly a decline in brain tryptophan concentrations.…”

Section: Self-rating Scalesmentioning

confidence: 99%

“…The plasma ratio of tryptophan and large amino acids after ingestion of a tryptophan-supplemented amino acid beverage, comparable to the one we used, suggests that some decrease occurred in tryptophan availability at the carrier, and also possibly a decline in brain tryptophan concentrations. 53,54 Nevertheless, the depletion of brain tryptophan must have been much greater in that group of patients receiving the tryptophan-free amino acid beverage. Thus, our control treatment to TD was conservative and can be assumed to be a reasonable control because most subjects relasped after the recovery night, which is the general pattern of mood changes following SD, 25 whereas the TD subjects behaved unusually by remaining well.…”

Section: Self-rating Scalesmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Tryptophan Depletion in Drug-Free Depressed Patients Who Responded to Total Sleep Deprivation

Neumeister¹,

Praschak-Rieder²,

Heßelmann³

et al. 1998

Arch Gen Psychiatry

View full text Add to dashboard Cite

show abstract

Section: Self-rating Scalesmentioning

confidence: 99%

Section: Self-rating Scalesmentioning

confidence: 99%

Effects of Tryptophan Depletion in Drug-Free Depressed Patients Who Responded to Total Sleep Deprivation

Neumeister¹,

Praschak-Rieder²,

Heßelmann³

et al. 1998

Arch Gen Psychiatry

View full text Add to dashboard Cite

show abstract

“…However, the significance of these findings remains unclear since tryptophan but not serotonin can cross the human blood-brain barrier. CSF levels of tryptophan were found inversely related to tic severity [27], while comorbidities have been associated with the depletion of tryptophan [28]. In another study whole blood tryptophan levels were found to be significantly decreased in TS compared to normal controls, while whole blood serotonin levels were measured within the normal range [25].…”

Section: Findings From Laboratory Studiesmentioning

confidence: 99%

The Pathophysiological Role of the Serotonergic System in Tourette Syndrome

Müller-Vahl¹

2007

CPSR

View full text Add to dashboard Cite

Tourette syndrome (TS) is defined as a chronic motor and vocal tic disorder. Because dopamine blocking drugs reduce tics it has been suggested that the dopaminergic system is pathophysiologically involved. However, comorbidities such as obsessive-compulsive behavior (OCB), depression, and anxiety are often associated suggesting that imbalances among other neurotransmitter systems may also exist. An increasing body of evidence points to an involvement of the serotonergic system. Serotonin reuptake inhibitors are effective in the treatment of comorbid OCB, depression, and anxiety. Levels of serotonin (5-hydroxytryptamine; 5-HT), the primary metabolite 5-hydroxyindoleacetic acid (5-HIAA), and tryptophan, respectively, have been found to be reduced not only in blood and CSF but also in different brain regions. In addition, neuroimaging studies demonstrated a significant reduction in serotonin transporter binding ratios in TS compared to controls. In addition, alterations in 5-HT 2A receptor binding and tryptophan metabolism have been demonstrated. Recent genetic studies suggested a pathogenetic role of polymorphic variation(s) of the novel 5-HT synthesizing enzyme tryptophan hydroxylase 2 (TPH2) in TS. In summary, several findings from clinical, laboratory, neuroimaging and genetic studies strongly support the etiological relevance of the serotonergic system in TS.

show abstract