Replication  
Serotonergic marker Aa Bb Putative serotonergic mechanism
Lower plasma L-TRP and L-TRP/CAA S - / + + + Lowered availability of L-TRP
Higher plasma TRP clearance after TRP

loading

S - / + + Lowered availability of L-TRP through excessive peripheral catabolism
Higher urinary xanthurenic acid excretion

after TRP loading

S - / + Induction of liver pyrrolase-nicotinamide pathway
Lower plasma TRP in relation to clinical

response to serotonergic antidepressants

IS + + + Lower TRP availability predicts favorable outcome to serotonergic drugs
Induction of depressive symptoms by TRP

depletion techniques

S + + Lowered TRP availability is related to depressive phenomenology
Lower platelet 5-HT uptake S - -/+ + Indicative of lower 5-HT transporter
Lower platelet imipramine binding S - -/+ + + Indicative of lower 5-HT transporter
Lower platelet paroxetine binding S - - No indication of abnormal 5-HT transporter
Lower platelet or plasma 5-HT levels S + Indicative of lower 5-HT storage or release
Lower postmortem brain TRP, 5-HT, 5-HIAA S - / + Lower central 5-HT turnover/activity
Lower CSF 5-HIAA concentrations S - - - /+ + Lower central 5-HT turnover/activity
Higher platelet 5-HT2 receptor binding S + + Indicative of up-regulated (central?) 5-HT2

receptors

Higher postmortem brain 5-HT2 receptor

binding

S - /+ + + Up-regulated central 5-HT2 receptors

(prefrontal cortex)

Lower 5-HT2 antagonist-induced slow wave

sleep

S + Up-regulated central 5-HT2 receptors
Lower postmortem brain 5-HT1A receptor

binding

S - / + + Down-regulated central 5-HT1A receptors/hippocampus
Lower TRP-induced prolactin S - / + + + Indicative of lower central presynaptic 5-HT activity or postsynaptic receptor responsivity
Higher TRP-induced cortisol S - / + + Indicative of up-regulated central 5-HT2 receptors
Higher 5-HTP-induced cortisol S - / + + + Indicative of up-regulated central 5-HT2 receptors
Lower fenfluramine-induced prolactin S - / + + + Indicative of lower central presynaptic 5-HT activity or postsynaptic receptor responsivity
Lower clomipramine-induced prolactin S + + Indicative of lower central presynaptic 5-HT activity or postsynaptic receptor responsivity
Lower buspirone-induced cortisol/production   -  
Lower ipsapirone-induced cortisol S + + Indicative of downregulated central 5-HT1A receptors
Higher TRP, fenfluramine, or clomipramine-induced prolactin responses to ADTc S + + ADT increase brain 5-HT activity (pre- or postsynaptic)
Lower 5-HTP-induced cortisol to ADT I 0 ADT may desensitize 5-HT2 receptors

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published 2000