European Psychiatry - Volume 41 - April 2017

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S350 25th European Congress of Psychiatry / European Psychiatry 41S (2017) S303–S364
2 Sapienza university of Rome, department of neurosciences, mental
health and sensory organs, Rome, Italy
3 École polytechnique fédérale de Lausanne, center for biomedical
imaging CIBM, Lausanne, Switzerland
4 Centre hospitalier universitaire vaudois, CHUV, center for
psychiatric neuroscience, Lausanne, Switzerland
5 École polytechnique fédérale de Lausanne, laboratory of functional
and metabolic imaging, Lausanne, Switzerland
∗ Corresponding author.
Recent evidences have consistently reported lower glutamate (Glu)
levels in various brain regions, including the medial prefrontal cor-
tex (mPFC), in chronic schizophrenia but findings in the early (EP)
or in the prodromal phase of the disorder are equivocal. Although
regular cannabis use has been associated with an increased risk
of subsequent psychosis and with a perturbed Glu signalling, to
date, the critical question of whether or not Glu abnormalities
exist in EP and are related to cannabis use remains unanswered.
Magnetic resonance spectroscopy was used to measure [GlumPFC]
of 35 EP subjects (18 of whom were regular cannabis users) and
33 healthy controls (HC). For correlative analysis, neuropsycho-
logical performances were scored by a comprehensive cognitive
battery. [GlumPFC] was lower in EP users comparing to both HC
and EP non-users (P= 0.001 and P = 0.01, respectively), while no
differences were observed between HC and EP non-users. In EP
users Glu declined with age (r= −0.46; P = 0.04) but this relation-
ship was not observed in non-users. Among neuropsychological
profiles, working memory was the only domain that differentiates
patients depending on their cannabis use, with users having poo-
rer performances. In summary, our research revealed that cannabis
use in EP is associated with Glu decreased levels, which are nor-
mally not seen in the early phase of the disorder. This finding is
in line with previous 1H-MRS studies in cannabis users without a
psychotic disorder and sheds light for the role of cannabis use in
the progression of the disease.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW0711
Molecular targets of the ethanol and
original anticonvulsant in the
treatment of alcohol dependence
T. Shushpanova ∗, T. Novozheeva , A. Solonskii , N. Bokhan ,
E. Markova
1 Mental health research institute, Tomsk national research medical
center, Russian academy of sciences, biological psychiatry, Tomsk,
Russia
2 Mental health research institute, Tomsk national research medical
center, Russian academy of sciences, department of addictive states,
Tomsk, Russia
3 Fundamental and clinical immunology research institute,
department of neuroimmunology, Novosibirsk, Russia
∗ Corresponding author.
Objective Chronic exposure to alcohol causes neuroadaptive
changes in the brain, which leads to the recurrence of the disease.
Promising in this area is to find new safe and effective pharmaco-
logical agents acting on molecular targets of influence of alcohol in
the CNS.
Methods Experiments were performed on male rats Wistar and
male mice (CBAxC57Bl/6)F1.U. Experimental animals were formed
alcohol dependence, based on long-term use of alcohol solution.
Animals in a state of alcohol dependence were injected original
anticonvulsant meta-chloro-benzhydryl-urea. We evaluated para-
meters orienting-exploratory behavior and emotional reactivity
of the animals in the test “open field”, the cellular and humo-
ral immune response. Properties of benzodiazepine receptors of
the brain examined radioreceptor method using selective ligands
[3H]flunitrazepam and [3H]Ro5-4864.
Results Chronic exposure to ethanol resulted in a significant
change in the parameters of the experimental animal behavior
and emotional reactivity in the test “open field”, observed sup-
pression of immune response (∼40%), and increase in the number
of receptors on 54.8–59.4% associated with reduced receptor affi-
nity. Administration of meta-chloro-benzhydryl-urea led to the
abandonment of the use of ethanol, recorded a correction of the
above immunological and behavioral disorders due to alcohol
intoxication. Properties of benzodiazepine receptors in the brain
of experimental animals receiving the drug at a dose of 100 mg/kg
for 14 days, indicators affinity and receptor density were close to
the values in the control group.
Conclusions Anticonvulsant has a modulating effect on the func-
tional activity of the nervous and immune systems, reduces
compulsive craving for alcohol.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW0712
Serotonergic modulation of cognition;
An acute challenge
N. Skandali ∗, J. Rowe , J. Deakin , T. Robbins , B. Sahakian
1 Addenbrooke’s hospital, psychiatry, Cambridge, United Kingdom
2 University of Cambridge, clinical neurosciences, Cambridge, United
Kingdom
3 University of Cambridge, psychiatry, Cambridge, United Kingdom
4 University of Cambridge, psychology, Cambridge, United Kingdom
∗ Corresponding author.
Abstract Serotonin is well known to affect the multifaceted
construct of impulsivity. Lowering brain serotonin levels is shown
to increase impulsive choice in delay-discounting tasks (1) but
improves response inhibition in stop-signal paradigms. (2) Admi-
nistration of the antidepressant citalopram in healthy people
increases tendency to perform go choices in a Go/No-Go task
independent of outcome valence (3). It is rather unclear thought
how serotonergic neurotransmission affects several aspects of
cognition. We administered a single dose of 20mg escitalo-
pram, a selective serotonin reuptake inhibitor, to 66 healthy
participants, aged 18–45 years old, in a double-blind, randomi-
zed, placebo-controlled, parallel-groups study. Acute escitalopram
administration had a beneficial effect on inhibitory control with
reduced stop-signal reaction time observed in the treatment group.
Participants made significantly more errors in a probabilistic lear-
ning task and had lower accuracy during the discrimination stage
in an instrumental learning task thus indicating a learning impair-
ment. More errors in the CANTAB intra-extra dimensional set shift
task were also observed in the escitalopram-treated group. Our fin-
dings following acute administration of a clinically relevant dose
of escitalopram show a dissociate role for serotonin in modula-
ting cognition mediated by a potentially differential modulation of
fronto-striatal loops.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW0713
Microstructural and metabolic
disorders in CC of juvenile
schizophrenia patients
M. Ublinskiy ∗, N. Semenova , T. Akhadov , I. Melnikov ,
D. Kupriyanov , I. Lebedeva , V. Kaleda
1 Children’s clinical and research institute emergency surgery and
trauma, radiology, Moscow, Russia