We investigated the effect of tryptophan depletion (tryptophan-free mixture) on locomotor activity in an animal model of schizophrenia, induced by acute administration of 5R,10S-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10-imine hydrogen maleate (MK-801), and the influence of the tryptophan-free mixture on the action of the typical antipsychotic haloperidol. Male rats were pre-treated with haloperidol 60 min after receiving the tryptophan-free mixture (or water). We measured total distance travelled in an open field during a 90-min period. Administration of the tryptophan-free mixture resulted in decreased levels of tryptophan, serotonin and its metabolite 5-hydroxyindolacetic acid in the frontal cortex. Serotonin depletion increased the total distance travelled by MK-801-treated rats, modified the inhibitory effect of haloperidol and normalized the locomotor activity pattern in the model of schizophrenia-like behaviour. The effect of the tryptophan-free mixture combined with the classical antipsychotic haloperidol in MK-801-treated rats indicates the possibly important role of the serotonergic system in the action of antipsychotics.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ejphar.2004.08.034 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Acute tryptophan depletion reduces nitric oxide synthase in the rat hippocampus.
Neurochem Res
December 2013
Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, People's Republic of China.
Acute tryptophan depletion (ATD) is extensively used to investigate the role of central serotonin (5-HT). However, several studies reported that ATD had no significant effect on central 5-HT concentration and some ATD-induced changes was independent of 5-HT in the rodent brain. Therefore, the potential mechanism of ATD might not be ascribed solely to changes in the central 5-HT system.
View Article and Find Full Text PDFOrigin of tryptophan fluorescence lifetimes part 1. Fluorescence lifetimes origin of tryptophan free in solution.
J Fluoresc
January 2014
Laboratoire de Biophysique Moléculaire, Université de Lille 1. Sciences et Technologies, Bâtiment C6, 59655, Villeneuve d'Ascq Cédex, France,
Fluorescence intensity decays of L-tryptophan free in polar, hydrophobic and mixture of polar-hydrophobic solvents were recorded along the emission spectrum (310-410 nm). Analysis of the data show that emission of tryptophan occurs with two lifetimes in 100% polar and hydrophobic environments. The values of the two lifetimes are not the same in both environments while their populations (pre-exponentials values) are identical.
View Article and Find Full Text PDFReduction of serotonergic neurons in the dorsal raphe due to chronic prenatal administration of a tryptophan-free diet.
Int J Dev Neurosci
April 2012
Cellular Biology & Physiology Department, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico.
Serotonin (5-HT) is a widely studied neurotransmitter which plays an important role in the development and proper functioning of the organism throughout life. The appearance of 5-HT system early in ontogeny suggests the hypothesis that 5-HT plays a regulatory role in neurodevelopment. This study investigated the effect of administration of a tryptophan deficient diet during prenatal development on the morphology and cell population of the dorsal raphe.
View Article and Find Full Text PDFEquivalent effects of acute tryptophan depletion on REM sleep in ecstasy users and controls.
Psychopharmacology (Berl)
October 2009
Psychopharmacology Unit, University of Bristol, Bristol, UK.
Introduction: This study sought to test the association between 3,4-methylenedioxymethamphetamine use, serotonergic function and sleep.
Materials And Methods: Ambulatory polysomnography was used to measure three nights sleep in 12 ecstasy users and 12 controls after screening (no intervention), a tryptophan-free amino acid mixture (acute tryptophan depletion (ATD)) and a tryptophan-supplemented control mixture.
Results: ATD significantly decreased rapid eye movement (REM) sleep onset latency, increased the amount of REM sleep and increased the amount of stage 2 sleep in the first 3 h of sleep.
Rapid tryptophan depletion as a treatment for acute mania: a double-blind, pilot-controlled study.
Bipolar Disord
December 2007
Ministry of Health Mental Health Center, Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva, Israel.
Objectives: Rapid reduction of up to 80% in plasma tryptophan level can be accomplished by administering an oral tryptophan-free amino acid solution, which induces hepatic protein synthesis and thereby depletes available plasma tryptophan. Rapid tryptophan depletion (RTD) has been shown to induce transient depressive symptoms in patients with remitted major depression. The effect of RTD in acutely manic patients has not been studied.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!