The ecological momentary assessment approach and the use of big data to analyse possible effects of urbanisation on mental health

Introduction

Smart healthcare monitoring allows detecting health conditions using Big Data, namely aggregated data concerning physiological and behavioral parameters. The continuous collection of data from smart-devices performed by the Ecological Momentary Assessment approach represents a promising application of Big Data.

Objectives

This preliminary study was aimed at developing a research protocol focused on the use of Big Data in evaluating the impact of urban environment, affected by a variety of potentially damaging anthropogenic actions, on illness relapses in Bipolar Disorders (BD).

Methods

This pilot study was designed by researchers from Departments of Psychiatry and Engineering (CIRIAF), University of Perugia. Environmental, physiological, and behavioral parameters and smart-devices aimed at collecting Big Data were identified. Subjects aged 18-65, affected by BD in current euthymic state referring to the University/General Hospital of Perugia will be recruited.

Results

Subjects will undergo a baseline visit and three monitoring visits during one year. Wearable devices will be provided for collecting data about environmental and physiological parameters. Behavioral data will be collected through smartphone accelerometers, GPS, and overall smartphone use. Big data will be stored into an online platform that will provide real-time feedback concerning the recorded variables. Clinical information concerning BD relapses will be collected. Machine learning techniques, integrated to deterministic analysis of urban environmental conditions, will be used to create possible predictive models for BD relapses.

Conclusions

The present project could allow the creation of a new operative platform for a better health management system correlating real-time Big Data to specific clinical features of BD.

Disclosure

No significant relationships.

Air pollutants and daily number of admissions to psychiatric emergency services: evidence for detrimental mental health effects of ozone

AIMS

Aim of the current study is to investigate the associations between daily levels of air pollutants (particulate matter, ozone, carbon monoxide, nitrogen dioxide) and daily admissions for mental disorders to the emergency department of two general hospitals in Umbria region (Italy).

METHODS

We collected data about daily admissions to psychiatric emergency services of two general hospitals, air pollutants' levels and meteorological data for the time period 1 January 2015 until 31 December 2016. We assessed the impact of an increase in air pollutants on the number of daily admissions using a time-series econometric framework.

RESULTS

A total of 1860 emergency department admissions for mental disorders were identified. We observed a statistically significant impact of ozone levels on daily admissions. The estimated coefficient of O3 is statistically significant at the 1% level. All other pollutants were not significantly associated with the number of daily admissions.

CONCLUSIONS

Short-term exposure to ozone may be associated with increased psychiatric emergency services admissions. Findings add to previous literature on existing evidence for air pollution to have an impact on mental health. Ozone may be considered a potential environmental risk factor for impaired mental health.

Real-world effectiveness of long acting aripiprazole: Treatment persistence and its correlates in the Italian clinical practice

OBJECTIVES

To identify the variables that are associated with persistence to Aripiprazole-Long Acting (A-LAI), in adult patients with schizophrenia.

METHODS

Observational, retrospective, non-interventional study involving 261 patients with schizophrenia.

RESULTS

Eighty-six percent of study subjects were persistent for at least 6 months. All subjects with baseline CGI-S of 1 or 2, 95% of subjects with CGI-S of 3, 86% with CGI-S of 4, 82% of subjects with CGI-S of 5, 73% of subjects with CGI of 6 and 90% of subjects with CGI of 7 were persistent. A-LAI treatment continuation rate was higher in patients with: 1) baseline CGI score ≤ 4; 2) schizophrenia dimension (LDPS) mania score ≤ 5; 3) psychotic spectrum schizoid score ≤ 11.

CONCLUSIONS

A relatively high number of patients (n = 225, 86%) were persistent to A-LAI for at least 6 months. Not surprisingly, very severe patients were more unlikely to be persistent. However, it is noteworthy that a large number of subjects with high CGI score at the time when A-LAI was started (82% of subjects with CGI-S of 5, 73% of subjects with CGI of 6 and 90% of subjects with CGI of 7) were persistent. Larger, controlled, prospective and longer studies are warranted.

The aggressor at the mirror: Psychiatric correlates of deliberate self-harm in male prison inmates

BACKGROUND

Deliberate self-harm (DSH) causes important concern in prison inmates as it worsens morbidity and increases the risk for suicide. The aim of the present study is to investigate the prevalence and correlates of DSH in a large sample of male prisoners.

METHODS

A cross-sectional study evaluated male prisoners aged 18+ years. Current and lifetime psychiatric diagnoses were assessed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders - DSM-IV Axis I and Axis II Disorders and with the Addiction Severity Index-Expanded Version. DSH was assessed with The Deliberate Self-Harm Inventory. Multivariable logistic regression models were used to identify independent correlates of lifetime DSH.

RESULTS

Ninety-three of 526 inmates (17.7%) reported at least 1 lifetime DSH behavior, and 58/93 (62.4%) of those reported a DSH act while in prison. After multivariable adjustment (sensitivity 41.9%, specificity 96.1%, area under the curve=0.854, 95% confidence interval CI=0.811-0.897, P<0.001), DSH was significantly associated with lifetime psychotic disorders (adjusted Odds Ratio aOR=6.227, 95% CI=2.183-17.762, P=0.001), borderline personality disorder (aOR=6.004, 95% CI=3.305-10.907, P<0.001), affective disorders (aOR=2.856, 95% CI=1.350-6.039, P=0.006) and misuse of multiple substances (aOR=2.024, 95% CI=1.111-3.687, P=0.021).

CONCLUSIONS

Borderline personality disorder and misuse of multiple substances are established risk factors of DSH, but psychotic and affective disorders were also associated with DSH in male prison inmates. This points to possible DSH-related clinical sub-groups, that bear specific treatment needs.

Not the same old madness: Evaluating the clinical profile of the “schizophrenia spectrum” disorders

Introduction

The “schizophrenia spectrum” concept allowed better identifying the psychopathology underpinning disorders including schizophrenia, schizoaffective disorder (SZA) and cluster A personality disorders (PD).

Aims

To compare the clinical portrait of the schizophrenia spectrum disorders, focusing on the impact of the affective dimension.

Methods

Inpatients at the acute psychiatric ward of Perugia (Umbria-Italy) were evaluated with the structured clinical interview for DSM-IV Axis I and Axis II disorders and diagnosed with a “schizophrenia spectrum” disorder according to DSM-IV-TR. The clinical evaluation was conducted using the positive and negative syndrome scale (PANSS). Pearson correlations of the different subscales in the three groups and between the negative scales with the affective symptom “depression” were conducted.

Results

The sample consisted of 72 inpatients (schizophrenia 55.6%, SZA 20% and cluster A PD 19.4%). The negative and the general psychopathology scales directly correlated at different degrees in the three groups (schizophrenia: r = 0.750; P < 0.001; SZA: r = 0.625, P = 0.006; cluster A PD: r = 0.541, P = 0.046). The symptom “depression” directly correlated with 5 out of 7 negative symptoms: blunted affect (r = 0.616, P < 0.001), emotional withdrawal (r = 0.643, P < 0.001), poor rapport (r = 0.389, P = 0.001), passive/apathetic social withdrawal (r = 0.538, P < 0.001), lack of spontaneity & flow of conversation (r = 0.399, P = 0.001).

Conclusions

Our study confirmed the existence of the “schizophrenia spectrum” with combined different disorders lying on a continuum in which negative symptoms mainly correlated with the psychopathological functioning. Noteworthy, the symptoms of the negative scale strongly correlated with the “depression” symptom, underlying the impact of the affective symptoms on the severity of the “schizophrenia spectrum” disorders.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Prevalence of insulin resistance and diabetes mellitus type II in bipolar disorders

Introduction

Bipolar disorder (BD) is associated with high morbidity and mortality. Patients are symptomatic almost half of their lives and experience significant disability. One subtype of BD is associated with a more chronic course, refractoriness to treatment and poor outcome. Diabetes mellitus type 2 (T2D) and insulin resistance (IR) have been identified as risk factors for this more severe form of BD.

Objectives and aims

We investigated the rates of IR and T2D in patients with BD and whether this comorbidity is associated with specific clinical features of BD such as rapid cycling or treatment resistance.

Methods

IR and T2D were screened in patients with BD types I or II, who were on stable treatment with mood stabilizers. The response to treatment was assessed by means of the Alda scale.

Results

In a preliminary sample, we made a new diagnosis of IR in 40% of patients. The 1% of this sample had a diagnosis of T2D. The treatment response was worse in BD patients with comorbid IR or T2D as compared to those without metabolic abnormalities.

Conclusions

These findings show that IR and T2D have high prevalence in BD patients and have negative impact on treatment response.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

A genome-wide association study of anorexia nervosa

Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome-wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2907 cases with AN from 14 countries (15 sites) and 14 860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery data sets. Seventy-six (72 independent) single nucleotide polymorphisms were taken forward for in silico (two data sets) or de novo (13 data sets) replication genotyping in 2677 independent AN cases and 8629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication data sets comprised 5551 AN cases and 21 080 controls. AN subtype analyses (1606 AN restricting; 1445 AN binge-purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P=3.01 × 10(-7)) in SOX2OT and rs17030795 (P=5.84 × 10(-6)) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P=5.76 × 10(-)(6)) between CUL3 and FAM124B and rs1886797 (P=8.05 × 10(-)(6)) near SPATA13. Comparing discovery with replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P=4 × 10(-6)), strongly suggesting that true findings exist but our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field.

Opposite modifications in circulating leptin and soluble leptin receptor across the eating disorder spectrum

Leptin is thought to modulate feeding behaviour, body weight and energy metabolism by acting through specific cellular receptors. Derangements of leptin production have been repeatedly reported in patients with anorexia nervosa (AN) or bulimia nervosa (BN), but no information has been provided on the functional status of leptin receptors in these disorders. Therefore, we measured plasma levels of leptin and its soluble receptor (Ob-Re) in a total of 130 women, including 22 patients with AN, 45 patients with BN, 18 patients with the binge-eating disorder (BED), 12 non-binge eating obese women and 33 healthy women. Circulating leptin was drastically reduced in underweight anorexics and normal-weight bulimics, but increased in overweight BED patients and non-binge-eating obese women. Conversely, plasma levels of Ob-Re were significantly increased in patients with AN or BN, but decreased in BED and non-binge-eating obese women. Significant inverse correlations were detected between plasma levels of leptin and those of Ob-Re in all the subject groups, except in non-binge-eating obese subjects. These results show, for the first time, that opposite modifications occur in circulating levels of leptin and Ob-Re across the eating-disorder spectrum. The relevance of these findings to the pathophysiology and treatment of eating disorders remains to be elucidated.

Plasma concentrations of amino acids in chronic schizophrenics treated with clozapine

Peripheral amino acid changes have been reported in schizophrenia, but results are not consistent. We measured serum levels of different amino acids in 11 neuroleptic-resistant schizophrenic patients before and after clozapine treatment and in 11 age- and sex-matched healthy subjects. The schizophrenic patients exhibited significantly higher levels of serum aspartate, glutamate, isoleucine, histidine and tyrosine and significantly lower concentrations of serum asparagine, tryptophan and serine. In patients, the ratio between tryptophan and large neutral amino acids (LNAA) was significantly lower than in matched controls, whereas the tyrosine/LNAA ratio did not differ significantly. Moreover, 12 weeks of clozapine administration significantly reduced serum levels of glutamate but did not restore the values observed in normal controls, nor did it affect other amino acid concentrations. These data show changes in serum amino acids that may influence central serotonergic, dopaminergic and glutamatergic transmission in neuroleptic-resistant schizophrenics.

Decreased blood levels of tumor necrosis factor-alpha in patients with obsessive-compulsive disorder

To investigate immune system function in obsessive-compulsive disorder (OCD) we measured plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) in 14 drug-free obsessive-compulsive patients and 14 matched healthy controls. No significant differences were observed between patients and controls in plasma levels of IL-1 beta and IL-6, whereas plasma levels of TNF-alpha were significantly lower (p = 0.001) in the former. Blood levels of prolactin did not differ between the two groups, whereas plasma cortisol concentrations were significantly higher in patients than in healthy subjects (p = 0.02). No significant correlation was found between immune parameters, on the one hand, and endocrine or psychopathological measures on the other. These results suggest that OCD is associated with a decreased production in TNF-alpha, but normal synthesis of IL-1 beta and IL-6.

Circulating leptin in patients with anorexia nervosa, bulimia nervosa or binge-eating disorder: relationship to body weight, eating patterns, psychopathology and endocrine changes

A decreased production of leptin has been reported in women with anorexia nervosa (AN) and has been attributed merely to the patients' reduced body fat mass. The extent to which eating patterns, purging behaviors, psychopathology and endocrine changes may contribute to the genesis of leptin alterations has not been deeply investigated. Therefore, we measured plasma levels of leptin, glucose and other hormones in three groups of eating disorder patients with different body weight (BW), eating patterns and purging behaviors. Sixty-seven women, 21 with AN, 32 with bulimia nervosa (BN), 14 with binge-eating disorder (BED) and 25 healthy females volunteered for the study. We found that circulating leptin was significantly reduced in AN and BN patients, but significantly enhanced in women with BED. In anorexics, plasma glucose was decreased, whereas plasma cortisol was enhanced; blood concentrations of 17beta-estradiol and prolactin (PRL) were reduced in both AN, BN and BED patients. In all subject groups, a strong positive correlation emerged between plasma levels of leptin and the subjects' BW or body mass index, but not between leptin and psychopathological measures, plasma glucose, cortisol, PRL and 17beta-estradiol. Since leptin was reduced in both underweight anorexics and normal weight bulimics, but increased in overweight BED women, who compulsively binge without engaging in compensatory behaviors, we suggest that factors other than BW may play a role in the determination of leptin changes in eating disorders.

Immunoendocrine findings in patients with eating disorders

Immune changes may occur in patients with anorexia nervosa (AN) or bulimia nervosa (BN), and a role for proinflammatory cytokines has been proposed in the pathogenesis of both disorders. We measured plasma levels of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), soluble forms of the cytokine receptor proteins gp130 and leukemia inhibitory factor receptor (LIF-R), the anti-inflammatory Clara cell 16-kD protein (CC16), prolactin (PRL), cortisol and 17beta-estradiol in 21 anorexic women, 21 bulimic women and 21 healthy females. As compared to healthy subjects, anorexics exhibited significantly increased plasma levels of gp130 and LIF-R, whereas bulimics had significantly decreased blood concentrations of CC16. No significant differences emerged in the blood levels of the remaining immune parameters. Both patient groups manifested higher plasma levels of cortisol and reduced plasma concentrations of PRL and 17beta-estradiol. In anorexics, a significant negative correlation was found between plasma levels of gp130 or LIF-R and the body mass index. These findings do not support the hypothesis that proinflammatory cytokines may play a pathogenetic role in eating disorders.

Reliability and validity of four alternative definitions of rapid-cycling bipolar disorder

OBJECTIVE

This study tested the reliability and validity of four definitions of rapid cycling.

METHOD

Two trained psychiatrists, using the Schedule for Affective Disorders and Schizophrenia, independently assessed 210 patients with bipolar disorder. They checked whether each patient met four definitions of rapid cycling: one consistent with DSM-IV criteria, one waiving criteria for duration of affective episodes, one waiving such criteria and requiring at least one switch from mania to depression or vice versa during the reference year, and one waiving duration criteria and requiring at least 8 weeks of fully symptomatic affective illness during the reference year. The interrater reliability was calculated by Cohen's kappa statistic. Patients who met each definition according to both psychiatrists were compared to those who did not meet any definition (nonrapid-cycling group) on demographic and clinical variables. All patients were followed up for 1 year.

RESULTS

Kappa values were 0.93, 0.73, 0.75, and 0.80, respectively, for the four definitions of rapid cycling. The groups meeting the second and third definitions included significantly more female and bipolar II patients than did the nonrapid-cycling group. Those two groups also had the lowest proportion of patients with a favorable lithium prophylaxis outcome and the highest stability of the rapid-cycling pattern on follow-up. The four groups of rapid-cycling patients did not differ significantly among themselves on any of the assessed variables.

CONCLUSIONS

The expression "rapid cycling" encompasses a spectrum of conditions. The DSM-IV definition, although quite reliable, covers only part of this spectrum, and the conditions that are excluded are very typical in terms of key validators and are relatively stable over time.

Prolactin hyperresponsiveness to D-fenfluramine in drug-free schizophrenic patients: a placebo-controlled study

BACKGROUND

Functional alterations in the central serotonergic system have been reported in schizophrenia but no conclusive data have been provided. In the present study, we investigated the prolactin (PRL) response to the selective serotonin (5-HT) releasing agent D-fenfluramine in both patients with schizophrenia and matched healthy subjects.

METHODS

Sixteen drug-free schizophrenics and 16 healthy subjects were randomized in a double-blind neuroendocrine test to D-fenfluramine (30 mg p.o.) or placebo. Blood PRL and cortisol concentrations were determined by radioimmunoassay, while plasma levels of D-fenfluramine were measured by mass spectrometry.

RESULTS

In schizophrenic patients, baseline plasma PRL levels were not different from controls, whereas plasma cortisol concentrations were significantly increased (p < .03). The PRL response to D-fenfluramine was significantly enhanced in patients as compared to matched control subjects (p < .005). Schizophrenics meeting Kane's criteria for previous nonresponse to typical neuroleptics exhibited a PRL response to D-fenfluramine significantly higher than non-drug-resistant patients (p < .04). No significant difference in plasma D-fenfluramine concentrations was observed between schizophrenic and healthy subjects.

CONCLUSIONS

These findings suggest a serotonergic hypersensitivity in chronic schizophrenia. This alteration seems to be peculiar to those patients refractory to typical neuroleptics.

Plasma levels of interleukin-6 and tumor necrosis factor alpha in chronic schizophrenia: effects of clozapine treatment

Plasma levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF alpha) were assessed in 17 chronic schizophrenic patients who had been drug-free for 3 weeks and in 17 age- and sex-matched healthy subjects. Plasma concentrations of both cytokines were measured again in 12 patients after a 10-week treatment with clozapine. Compared with healthy controls, drug-free schizophrenic patients exhibited similar plasma IL-6 concentrations, but significantly higher levels of TNF alpha. After clozapine treatment, blood concentrations of TNF alpha fell to normal levels. These preliminary data support an immune activation in drug-free schizophrenic patients and an effect of clozapine on immune parameters.

A crucial role of the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid subtype of glutamate receptors in piriform and perirhinal cortex for the initiation and propagation of limbic motor seizures

The role of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors in the initiation and propagation of limbic motor seizures in rats was examined by the intracerebral and systemic administration of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo (f) quinoxaline (NBQX), a selective antagonist of the AMPA subtype of glutamate receptor. Limbic motor seizures were evoked focally by the application of the gamma-aminobutyric acid receptor antagonist, bicuculline, into area tempestas, an epileptogenic site in the deep anterior piriform cortex. Before eliciting seizures, NBQX was applied focally into either 1) area tempestas or 2) perirhinal or posterior piriform cortex ipsilateral to the area tempestas from which seizures were evoked. In addition, pretreatment with i.p. NBQX was evaluated for anticonvulsant actions against area tempestas-evoked clonic or systemically evoked tonic seizures. In all conditions, a dose-dependent decrease in the severity of seizures was obtained with NBQX. With focal intracerebral administration, a dose of 500 pmol of NBQX consistently protected against limbic motor seizures, with partial protection achieved with 100 pmol. After i.p. administration, 2.5 and 5.0 mg/kg significantly protected the rats from both limbic motor seizures and tonic extensor seizures. No overt disturbance of spontaneous behavior was associated with the anticonvulsant doses of NBQX. Moreover, both forebrain substrates of limbic motor seizures and hindbrain substrates of tonic extensor seizures were highly susceptible to disruption by NBQX. The results indicate that AMPA subtype of glutamate receptors are crucial mediators of seizure propagation via perirhinal and piriform cortics.

Suppression of nocturnal plasma melatonin levels by evening administration of sodium valproate in healthy humans

To investigate the role of gamma-aminobutyric acid (GABA) in the modulation of human melatonin production, we studied the effects of the acute administration of the GABAergic drug, sodium valproate (VAL), on nocturnal blood melatonin levels in healthy subjects. To this purpose, 4 healthy men and 3 healthy women, aged 24-33 years, underwent three experimental sessions in which they received orally 400 mg VAL, 800 mg VAL, or placebo, in random order, according to a double-blind design. The drug administration was done at 19:00 hours; thereafter, blood samples were collected over the night, in dark conditions with the help of a red light. As compared to placebo, VAL, at the dosage of both 400 and 800 mg, significantly suppressed nocturnal blood melatonin levels, the higher dose being slightly more effective than the lower one. The maximum suppression coincided with the highest plasma levels of valproic acid. These findings support the view that endogenous GABA may participate in the modulation of the activity of the human pineal gland.

Cortisol response to d-fenfluramine in patients with obsessive-compulsive disorder and in healthy subjects: evidence for a gender-related effect

In order to evaluate serotonergic function in obsessive-compulsive disorder (OCD), plasma cortisol response to d-fenfluramine (30 mg p.o.) was examined in 20 drug-free obsessive-compulsive patients (10 males and 10 females) and in 20 age- and sex-matched healthy subjects, under double-blind, placebo-controlled conditions. We found that: (a) baseline plasma cortisol secretion was significantly increased in patients with OCD; (b) in healthy subjects, the cortisol response to d-fenfluramine was evident in women, but no in men; (c) plasma cortisol response to the serotonergic challenge did not differ between patients and controls, but it was significantly reduced in female patients as compared to healthy women. These results demonstrate a hyperactivity of the hypothalamo-pituitary-adrenal axis in obsessive-compulsive patients and suggest a dysfunction of 5-HT transmission in female patients.

The anticonvulsant action of fluoxetine in substantia nigra is dependent upon endogenous serotonin

Fluoxetine, a serotonin (5-HT) reuptake inhibitor, has been documented to exert a protective action against convulsive seizures in animal models, when administered either systemically, or focally into substantia nigra. It is likely that the mechanism of anticonvulsant action of fluoxetine is due to an enhancement of endogenous 5-HT transmission. To evaluate this possibility in the context of the anticonvulsant action of intranigral fluoxetine, we examined the influence of 5-HT-mediated transmission in substantia nigra on seizure susceptibility in a rat model of focally evoked complex partial seizures. In addition to fluoxetine (3.5 nmol), we found that the directly acting 5-HT receptor agonists, 1-[3-(trifluoromethyl)phenyl]piperazine (TFMPP) (10 nmol), 1-(3-chlorophenyl)piperazine (m-CPP) (7.4 nmol), gepirone (70 nmol) and 2-dipropylamino-8-hydroxy-1,2,3,4-tetrahydronaphthalene hydrobromide (8-OH-DPAT) (10 nmol), when microinjected bilaterally into substantia nigra, protected rats from limbic motor seizures evoked focally from area tempestas, an epileptogenic site in the deep rostral piriform cortex. This indicates that multiple 5-HT receptor subtypes in substantia nigra may contribute to seizure regulation. Consistent with this, the 5-HT antagonist, metergoline, partially reversed the anticonvulsant action of intranigral fluoxetine. Depletion of endogenous 5-HT, by pretreatment with parachlorophenylalanine (PCPA), completely prevented the anticonvulsant action of intranigral fluoxetine, without modifying the anticonvulsant effect of intranigral TFMPP. These findings support the proposal that the anticonvulsant action of fluoxetine in substantia nigra is due to an enhancement of the synaptic action of endogenous 5-HT in substantia nigra which in turn is mediated via multiple 5-HT receptors. Endogenous 5-HT transmission in substantia nigra is therefore capable of limiting the development and propagation of seizure activity generated in limbic circuits.

Plasma melatonin and cortisol circadian patterns in patients with obsessive-compulsive disorder before and after fluoxetine treatment

The circadian rhythms of melatonin and cortisol were evaluated in seven outpatients with obsessive-compulsive disorder (OCD) before and after 8 weeks of fluoxetine treatment (20 mg/day in the first 2 weeks, and 40 mg/day afterwards), and in seven healthy subjects matched to patients on age, sex and season of testing. The results confirm our previous findings of a decreased 24-h production of melatonin (p < .05; two-way ANOVA with repeated measures) and of an increased circadian secretion of cortisol (p < .01) in OCD patients with respect to matched controls, and show, for the first time, that these hormonal alterations do not significantly change after 2 months of fluoxetine administration, in spite of a good clinical improvement. These data suggest that the normalization of the biochemical changes underlying the altered endocrine parameters in obsessive-compulsive patients is not necessary for effective therapy or clinical remission.

Posterior piriform and perirhinal cortex relay seizures evoked from the area tempestas: role of excitatory and inhibitory amino acid receptors

The functional relationship between the area tempestas (AT), an epileptogenic site within the deep prepiriform cortex, and the regions in the posterior piriform cortex which are innervated by AT, were studied in the rat. The GABAA receptor agonist, muscimol (390 pmol) was microinjected unilaterally into the posterior piriform cortex and adjacent regions in the same hemisphere from which seizures were evoked by focal application of bicuculline into AT. Pretreatment with muscimol into either the ventral posterior piriform cortex or perirhinal cortex, protected against the bilateral clonic seizures evoked from the ipsilateral AT. No seizure protection was obtained when muscimol was placed into adjacent areas of amygdala, entorhinal cortex, neocortex and ventral hippocampus. Seizure protection was also obtained when kynurenic acid, but not 2-amino-7-phosphonoheptanoic acid, was microinjected into the ventral posterior piriform cortex, suggesting that glutamate transmission mediated via non-N-methyl-D-aspartate (non-NMDA) receptors is required for the relay of seizure discharge through this region. Our data indicate that a specific region of the temporal cortex, the posterior piriform and perirhinal area, functions as a critical link in the propagation of limbic seizures evoked from AT.

Anticonvulsant effect of intranigral fluoxetine

Bilateral focal injections of the serotonin uptake inhibitor, fluoxetine (1.75-7.0 nmol) into substantia nigra (SN) protected against convulsive seizures evoked by the focal injection of bicuculline methiodide into area tempestas, an epileptogenic site within the deep prepiriform cortex. Injection of fluoxetine unilaterally in SN or bilaterally into a site dorsal to SN was not anticonvulsant. Blockade of nigral gamma-aminobutyric acid (GABA) receptors with bicuculline in SN did not reverse the anticonvulsant action of intranigral fluoxetine. These data suggest that serotonergic transmission in SN exerts a seizure suppressing action which is independent of GABA transmission in SN.

Sleep deprivation decreases mu and delta opioid receptor binding in the rat limbic system

Sleep deprivation induced by the platform technique is considered to be a heavy stressful situation in rats. At the end of the sleep deprivation period (72 h) the rat displayed particular behavior characterized by wakefulness, a high degree of motor and exploratory activity, increased alertness and reactivity to environmental stimuli. Our previous results indicated that this behavior was antagonized by the administration of the opioid receptor antagonist naloxone and increased by opioid agonists. In this paper we show that concomitantly with this behavior, a decreased Bmax of mu and delta opioid receptors is present in the limbic system of these animals. These data suggest an active role of limbic mu and delta receptors in the generation of arousal and insomnia related to sleep deprivation induced stress.