[Show abstract][Hide abstract] ABSTRACT: In 17 healthy young men who had a parent with documented early coronary disease, ratings of type A behaviour correlated with upregulated lymphocyte Beta2 receptor density and inversely with the ratio of platelet Alpha1 to lymphocyte Beta2 receptor density ratio. This indicates a correlation of type A behaviour with receptor based determinations of increased peripheral Alpha-adrenergic balance, consistent with increased coronary arterial vasoconstriction, perhaps leading to coronary artery disease.
[Show abstract][Hide abstract] ABSTRACT: Low gamma-aminobutyric acid (GABA) is implicated in both anxiety and depression pathophysiology. They are often comorbid, but most clinical studies have not examined these relationships separately. We investigated the relationship of cerebrospinal fluid (CSF) free GABA to the anxiety and depression components of a major depressive episode (MDE) and to monoamine systems.
Depression and Anxiety 05/2014; · 4.61 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Major depressive disorder (MDD) is associated with low levels of omega-3 polyunsaturated fatty acids (PUFAs), holding promise for new perspectives on disease etiology and treatment targets. As aggressive and impulsive behaviors are associated with low omega-3 PUFA levels in some clinical contexts, we investigated plasma PUFA relationships with trait aggression and impulsivity in patients with MDD. Medication-free MDD patients (n=48) and healthy volunteers (HV, n=35) were assessed with the Brown-Goodwin Aggression Inventory. A subset (MDD, n=39; HV, n=33) completed the Barratt Impulsiveness Scale. Plasma PUFAs eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and arachidonic acid (AA, 20:4n-6) were quantified and ln-transformed to mitigate distributional skew. Ln-transformed PUFA (lnPUFA) levels were predictors in regression models, with aggression or impulsivity scores as outcomes, and cofactors of sex and diagnostic status (MDD with or without a history of substance use disorder [SUD], or HV). Interactions were tested between relevant PUFAs and diagnostic status. Additional analyses explored possible confounds of depression severity, self-reported childhood abuse history, and, in MDD patients, suicide attempt history. Among PUFA, lnEPA but not lnDHA predicted aggression (F1,76=12.493, p=0.001), and impulsivity (F1,65=5.598, p=0.021), with interactions between lnEPA and history of SUD for both aggression (F1,76=7.941, p=0.001) and impulsivity (F1,65=3.485, p=0.037). Results remained significant when adjusted for childhood abuse, depression severity, or history of suicide attempt. In conclusion, low EPA levels were associated with aggression and impulsivity only in patients with MDD and comorbid SUD, even though in most cases SUD was in full sustained remission.
[Show abstract][Hide abstract] ABSTRACT: Background
Considerable evidence suggests that testosterone may play a role in the pathophysiology of mood disorders in females. This is the first prospective study to examine whether blood testosterone levels predict suicide attempts in females with bipolar disorder.
Females with a DSM-IV diagnosis of a bipolar disorder in a depressive or mixed episode with at least one past suicide attempt were enrolled. Demographic and clinical parameters were assessed and recorded. Plasma testosterone was assayed using a double antibody radioimmunoassay procedure. Patients were followed up prospectively for up to 2.5 years.
At baseline, testosterone levels positively correlated with the number of previous major depressive episodes and suicide attempts. Cox proportional hazards regression analysis found that higher baseline testosterone levels predicted suicide attempts during the follow-up period.
A limitation of the study is that the sample size is modest. Another limitation is that we did not have a bipolar nonattempter or healthy volunteer control group for comparison.
Testosterone levels may predict suicidal behavior in women with bipolar disorder.
Journal of Affective Disorders. 01/2014; 166:98–102.
[Show abstract][Hide abstract] ABSTRACT: The hypothalamic-pituitary-adrenal (HPA) axis is dysfunctional in a subgroup of mood disorders.
We compared cortisol and adrenocorticotropic hormone (ACTH) responses in major depression and healthy volunteers to the combined dexamethasone suppression-corticotrophin-releasing hormone stimulation (DEX-CRH) test. Unlike other published studies, the study patients were medication-free and the healthy volunteers did not have first-degree relatives with a mood or psychotic disorder. Demographics, DSM-IV diagnoses and other clinical parameters were evaluated in major depressive disorder (MDD) and healthy control groups. Participants received an oral dose of 1.5mg dexamethasone at 11pm the day before CRH administration. On the following day, at 3pm, 100µg of ovine CRH was infused. Blood samples for determination of cortisol and ACTH were collected every 15min from 3pm to 4:15pm. Cortisol and ACTH responses were calculated as areas under the curve.
Controlling for age, baseline (i.e., post-dexamethasone) ACTH levels were higher in depressed patients compared to controls (p=0.01). There was a trend for higher ACTH responses in depressed patients compared to the control group (p=0.08). In depressed patients, cortisol and ACTH responses correlated positively with age, duration of illness and number of hospitalizations.
Because of the cross-sectional study design we can only evaluate the nature of potential HPA axis disturbances that were present in patients when they are acutely depressed.
Feedback inhibition of ACTH secretion by cortisol is compromised in MDD, and this is independent of an age effect on the HPA axis function.
Journal of affective disorders 07/2013; · 3.76 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although lower levels of omega-3 polyunsaturated fatty acids (PUFAs) are found in major depressive disorder, less is known about PUFA status and anxiety disorders.
Medication-free participants with DSM-IV-defined major depressive disorder (MDD), with (n = 18) and without (n = 41) comorbid DSM-IV anxiety disorders, and healthy volunteers (n = 62) were recruited from October 2006 to May 2010 for mood disorder studies at the New York State Psychiatric Institute. Participants were 18-73 years of age (mean age, 35.8 ± 12.6 years). Depression and anxiety severity was assessed using depression and anxiety subscales from the 17-item Hamilton Depression Rating Scale. Plasma PUFAs eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) and the ratio of arachidonic acid (AA; 22:4n-6) to EPA (AA:EPA) were quantified. This secondary analysis employed analysis of variance with a priori planned contrasts to test for diagnostic group differences in log-transformed PUFA levels (logDHA, logEPA, and logAA:EPA).
Plasma levels of logDHA (F2,118 = 4.923, P = .009), logEPA (F2,118 = 6.442, P = .002), and logAA:EPA (F2,118 = 3.806, P = .025) differed across groups. Participants with MDD had lower logDHA (t118 = 2.324, P = .022) and logEPA (t118 = 3.175, P = .002) levels and higher logAA:EPA levels (t118 = -2.099, P = .038) compared with healthy volunteers. Lower logDHA (t118 = 2.692, P = .008) and logEPA (t118 = 2.524, P = .013) levels and higher logAA:EPA levels (t118 = -2.322, P = .022) distinguished anxious from nonanxious MDD. Depression severity was not associated with PUFA plasma levels; however, anxiety severity across the entire sample correlated negatively with logDHA (rp = -0.22, P = .015) and logEPA (rp = -0.25, P = .005) levels and positively with logAA:EPA levels (rp = 0.18, P = .043).
The presence and severity of comorbid anxiety were associated with the lowest EPA and DHA levels. Further studies are needed to elucidate whether omega-3 PUFA supplementation may preferentially alleviate MDD with more severe anxiety.
The Journal of Clinical Psychiatry 07/2013; 74(7):732-8. · 5.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE: To determine whether starting antidepressant medication at the start of electroconvulsive therapy (ECT) reduces post-ECT relapse and to determine whether continuation pharmacotherapy with nortriptyline (NT) and lithium (Li) differs in efficacy or adverse effects from continuation pharmacotherapy with venlafaxine (VEN) and Li. METHODS: During an acute ECT phase, 319 patients were randomized to treatment with moderate dosage bilateral ECT or high-dosage right unilateral ECT. They were also randomized to concurrent treatment with placebo, NT, or VEN. Of 181 patients to meet post-ECT remission criteria, 122 (67.4%) participated in a second continuation pharmacotherapy phase. Patients earlier randomized to NT or VEN continued on the antidepressant, whereas patients earlier randomized to placebo were now randomized to NT or VEN. Lithium was added for all patients who were followed until relapse or 6 months. RESULTS: Starting an antidepressant medication at the beginning of the ECT course did not affect the rate or timing of relapse relative to starting pharmacotherapy after ECT completion. The combination of NT and Li did not differ from VEN and Li in any relapse or adverse effect measure. Older age was strongly associated with lower relapse risk, whereas the type of ECT administered in the acute phase and medication resistance were not predictive. Across sites, 50% of the patients relapsed, 33.6% continued in remission 6 months after ECT, and 16.4% dropped out. CONCLUSIONS: Starting an antidepressant medication during ECT does not affect relapse, and there are concerns about administering Li during an acute ECT course. Nortriptyline and VEN were equally effective in prolonging remission, although relapse rates after ECT are substantial despite intensive pharmacology. As opposed to the usual abrupt cessation of ECT, the impact of an ECT taper should be evaluated.
[Show abstract][Hide abstract] ABSTRACT: The best known neurobehavioral effects of testosterone are on sexual function and aggression. However, testosterone and other androgens may be involved in the pathophysiology of mood disorders and suicidal behavior. This is the first study to examine whether there is a relation between testosterone levels and clinical parameters in bipolar suicide attempters.
Patients with a DSM-IV diagnosis of a bipolar disorder (16 males and 51 females), in a depressive or mixed episode with at least one past suicide attempt were enrolled. Demographic and clinical parameters, including lifetime suicidal behavior, were assessed and recorded. Plasma testosterone was assayed using a double antibody radioimmunoassay procedure.
The number of major depressive episodes, the maximum lethality of suicide attempts, and the testosterone levels were higher in men compared to women. Current suicidal ideation scores were higher in women compared to men. Controlling for sex, we found that testosterone levels positively correlated with the number of manic episodes and the number of suicide attempts.
Our findings are consistent with previous observations of the association between testosterone levels and parameters of mood and behavior. This study suggests that testosterone levels may be related to the course of bipolar disorder and suicidal behavior. Further studies of the role of testosterone in the neurobiology of mood disorders and suicidal behavior are merited.
Journal of Psychiatric Research 07/2012; 46(10):1267-71. · 4.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In utero exposure to tetrahydrocannabinol, the psychoactive component of marijuana, is associated with an increased risk for neurodevelopmental defects in the offspring by interfering with the functioning of the endocannabinoid (eCB) system. At the present time, it is not clearly known whether the eCB system is present before neurogenesis. Using an array of biochemical techniques, we analyzed the levels of CB1 receptors, eCBs (AEA and 2-AG), and the enzymes (NAPE-PLD, DAGLα, DAGLβ, MAGL, and FAAH) involved in the metabolism of the eCBs in chick and mouse models during development. The findings demonstrate the presence of eCB system in early embryo before neurogenesis. The eCB system might play a critical role in early embryogenesis and there might be adverse developmental consequences of in utero exposure to marijuana and other drugs of abuse during this period.
Birth Defects Research Part B Developmental and Reproductive Toxicology 02/2012; 95(2):137-50. · 1.97 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: While the etiology of depression is not clearly understood at the present time, this mental disorder is thought be a complex and multifactorial trait with important genetic and environmental contributing factors.
The role of the endocannabinoid (eCB) system in depressive behavior was examined in Wistar Kyoto (WKY) rat strain, a genetic model of depression. Our findings revealed selective abnormalities in the eCB system in the brains of WKY rats compared to Wistar (WIS) rats. Immunoblot analysis indicated significantly higher levels of fatty acid amide hydrolase (FAAH) in frontal cortex and hippocampus of WKY rats with no alteration in the level of N-arachidonyl phosphatidyl ethanolamine specific phospholipase-D (NAPE-PLD). Significantly higher levels of CB1 receptor-mediated G-protein coupling and lower levels of anandamide (AEA) were found in frontal cortex and hippocampus of WKY rats. While the levels of brain derived neurotropic factor (BDNF) were significantly lower in frontal cortex and hippocampus of WKY rats compared to WIS rats, pharmacological inhibition of FAAH elevated BDNF levels in WKY rats. Inhibition of FAAH enzyme also significantly increased sucrose consumption and decreased immobility in the forced swim test in WKY rats.
These findings suggest a critical role for the eCB system and BDNF in the genetic predisposition to depressive-like behavior in WKY rats and point to the potential therapeutic utility of eCB enhancing agents in depressive disorder.
PLoS ONE 01/2012; 7(5):e36743. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: There are mixed reports on nicotine's effects on alcohol-induced impairment in cognitive performance and behavior in humans. The main objective of this study was to characterize the interactive effects of acute intravenous (IV) alcohol and nicotine administration on behavior and cognition in healthy nonsmokers.
Healthy subjects aged 21-44 years participated in 3 test days. On each test day, they received in a double-blind randomized manner one of three IV alcohol infusion conditions using a "clamp": placebo, targeted breathalyzer of 40 mg%, or targeted breathalyzer of 80 mg%. Alcohol infusion was delivered over 20 min and lasted for 120 min. They also received both placebo and active nicotine in a fixed order delivered intravenously. Placebo nicotine was delivered first over 10 min at the timepoint when the breath alcohol was "clamped"; active nicotine (1.0 mcg/kg/min) was delivered for 10 min, 70 min after the alcohol infusion was clamped. Subjective effects of alcohol were measured using the Biphasic Alcohol Effects Scale and the Number of Drinks Scale. Cognitive inhibition and attention were measured by the Continuous Performance Task-Identical Pairs and working memory by the Rey Auditory Verbal Learning Task (RAVLT).
Nicotine significantly reversed subjective intoxication and sedation of alcohol at the low dose. Alcohol impaired performance on the RAVLT, and nicotine further impaired verbal learning and recall at both doses of alcohol.
The data showed that nicotine had an effect on subjective alcohol effects but did not reverse and actually worsened alcohol-induced deficits in memory.
Nicotine & Tobacco Research 12/2011; 14(5):596-606. · 2.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The present study was undertaken to examine whether genetically predetermined differences in components of the endocannabinoid system were present in the brain of Sardinian alcohol-preferring (sP) and Sardinian alcohol-non-preferring (sNP) rats, a pair of rat lines selectively bred for opposite alcohol preference. The effects of acquisition and maintenance of alcohol drinking, alcohol withdrawal, and alcohol re-exposure on the endocannabinoid system was also assessed in the striatum of sP rats. The findings revealed significantly higher density of the CB1 receptors and levels of CB1 receptor mRNA, CB1 receptor-mediated G-protein coupling, and endocannabinoids in the cerebral cortex, hippocampus and striatum of alcohol-naive sP rats than sNP rats. A significantly lower expression of mFAAH enzyme was evident in the hippocampus of alcohol-naive sP rats. Alcohol drinking (during both acquisition and maintenance phases) in sP rats resulted in a significant reduction in striatal CB1 receptor-mediated G-protein coupling whereas alcohol withdrawal attenuated this effect. Alcohol consumption was also associated with markedly increased levels of endocannabinoids in the striatum. Co-administration of the CB1 receptor antagonist, rimonabant (SR141716A) reduced alcohol intake, and reversed alcohol-induced changes in CB1 receptor-mediated G-protein activation. These findings provided a new insight into a potential genetic basis of excessive alcohol consumption, suggesting innate differences in the endocannabinoid system might be associated with higher alcohol preference in sP rats. The data also indicate a modulation of CB1 receptor-mediated signaling following alcohol consumption, and further strengthen the potential of the endocannabinoid system as a target for the treatment of alcohol related behaviors.
[Show abstract][Hide abstract] ABSTRACT: The role of n-3 polyunsaturated fatty acids (PUFAs) in psychiatric illness is a topic of public health importance. This report describes development and biomarker validation of a 21-item, self-report food frequency questionnaire (FFQ) intended for use in psychiatric research to assess intake of α-linolenic acid (18:3n-3 [ALA]), docosahexaenoic acid (22:6n-3 [DHA]), and eicosapentaenoic acid (20:5n-3 [EPA]). In a cross-sectional study conducted from September 2006 to September 2008, sixty-one ethnically diverse adult participants with (n=34) and without (n=27) major depressive disorder completed this n-3 PUFA FFQ and provided a plasma sample. Plasma levels of n-3 PUFAs EPA and DHA, and n-6 PUFA arachidonic acid (20:4n-6 [AA]) were quantified by gas chromatography. Using Spearman's ρ, FFQ-estimated intake correlated with plasma levels of DHA (r=0.50; P<0.0001) and EPA (r=0.38; P=0.002), but not with ALA levels (r=0.22; P=0.086). Participants were classified into quartiles by FFQ-estimated intake and plasma PUFA concentrations. Efficacy of the FFQ to rank individuals into same or adjacent plasma quartiles was 83% for DHA, 78.1% for EPA, and 70.6% for ALA; misclassification into extreme quartiles was 4.9% for DHA, 6.5% for EPA, and 8.2% for ALA. FFQ-estimated EPA intake and plasma EPA were superior to plasma AA levels as predictors of the plasma AA to EPA ratio. This brief FFQ can provide researchers and clinicians with valuable information concerning dietary intake of DHA and EPA.
Journal of the American Dietetic Association 01/2011; 111(1):117-123.e1-2. · 3.80 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: DAR-0100A, the active enantiomer of dihydrexidine, is a potent dopamine D1 agonist under investigation for treatment of cognitive impairment and negative symptoms of schizophrenia. We measured the dose-occupancy relationship for DAR-0100A at D1 receptors using positron emission tomography (PET) imaging in baboons with [(11)C] NNC112 and its binding to D2 with [(11)C] raclopride. Two baboons were scanned with [(11)C] NNC112 at baseline and after three different doses of DAR-0100A. Two baboons were scanned with [(11)C] raclopride at baseline and after one dose of DAR-0100A. Occupancy (ΔBP(ND)) was computed in the striatum and cortex. A clear relationship was observed between plasma concentration of DAR-0100A and ΔBP(ND). ΔBP(ND) was larger in the striatum than in the cortex, consistent with reports showing that 25% of [(11)C] NNC112 BP(ND) in the cortex is attributed to 5-HT(2A). Plasma EC(50) estimates ranged from 150 to 550 ng/mL according to the constraints on the model. There was no detectable effect of DAR-0100A on [(11)C] raclopride BP(ND). These data suggest that at doses likely to be administered to patients, occupancy will not be detectable with [(11)C] NNC112 PET and binding of DAR-0100A to D2 will be negligible. This is the first demonstration with PET of a significant occupancy by a full D1 agonist in vivo.
Journal of cerebral blood flow and metabolism: official journal of the International Society of Cerebral Blood Flow and Metabolism 01/2011; 31(1):293-304. · 5.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The use of PET and SPECT endogenous competition-binding techniques has contributed to the understanding of the role of dopamine (DA) in several neuropsychiatric disorders. An important limitation of these imaging studies is the fact that measurements of changes in synaptic DA have been restricted to the striatum. The ligands previously used, such as [(11)C]raclopride and [(123)I]IBZM, do not provide sufficient signal-to-noise ratio to quantify D(2) receptors in extrastriatal areas, such as cortex, where the concentration of D(2) receptors is much lower than that in the striatum. Recently, we published a comparison study of the ability of two high-affinity DA D(2) radioligands [(11)C]FLB 457 and [(11)C]fallypride to measure amphetamine-induced changes in DA transmission in the human cortex. Our findings support the use of [(11)C]FLB 457 to measure changes in cortical synaptic DA induced by amphetamine. The goal of this study is to examine the effects of DA depletion with α-methyl-para-tyrosine (α-MPT) on [(11)C]FLB 457 binding in the cortex. Six healthy volunteers underwent two PET scans, first under control conditions and subsequently after DA depletion. The simplified reference tissue model as well as kinetic modeling with an arterial input function was used to derive the binding potential (BP(ND)) in seven cortical regions. We found no effect of DA depletion with α-MPT on [(11)C]FLB 457 binding in any of the regions examined. In contrast to the measurement of DA release, the combination of low D(2) receptor density and low basal DA levels in the cortex greatly reduce the power to detect alterations in [(11)C]FLB 457 binding secondary to DA depletion.
[Show abstract][Hide abstract] ABSTRACT: The mechanism of action of electroconvulsive therapy (ECT) in treating major depression is unknown. We studied two candidate mechanisms through inhibiting simultaneously the synthesis of noradrenaline and serotonin in patients immediately after successful treatment with ECT using a randomised, placebo-controlled, double-blind crossover design. There were no significant changes in depression scores under any experimental conditions, or between the amine-depleted and placebo groups despite reductions of 61% in serum homovanillic acid, 47% in 3-methoxy-4-hydroxyenylethyleneglycol, and 89% in serum tryptophan. Catecholamine and serotonin availability may not be necessary for maintaining the initial antidepressant response to ECT.
The British journal of psychiatry: the journal of mental science 06/2010; 196(6):493-4. · 6.62 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A long-standing version of the dopamine hypothesis of schizophrenia postulates that hyperactivity of dopaminergic transmission at D(2) receptors in the limbic striatum is associated with the illness and that blockade of mesolimbic D(2) receptors is responsible for the antipsychotic action of D(2) receptor antagonists.
To localize dopaminergic hyperactivity within the striatum in schizophrenia.
Inpatient research unit.
Eighteen untreated patients with schizophrenia and 18 healthy control subjects matched for age, sex, ethnicity, parental socioeconomic status, cigarette smoking, and weight.
Percentage change in dopamine D(2) receptor availability in striatal subregions within each subject measured by positron emission tomography with carbon 11-labeled raclopride before and during pharmacologically induced dopamine depletion.
In the associative striatum, acute dopamine depletion resulted in a larger increase in D(2) receptor availability in patients with schizophrenia (mean [SD], 15% [7%]) than in control subjects (10% [7%], P = .045), suggesting higher synaptic dopamine concentration. Within the associative striatum, this effect was most pronounced in the precommissural dorsal caudate (15% [8%] in patients vs 9% [8%] in controls, P = .03). No between-group differences were observed in the limbic and sensorimotor striatum.
These findings suggest that schizophrenia is associated with elevated dopamine function in associative regions of the striatum. Because the precommissural dorsal caudate processes information from the dorsolateral prefrontal cortex, this observation also suggests that elevated subcortical dopamine function might adversely affect performance of the dorsolateral prefrontal cortex in schizophrenia. On the other hand, the absence of a group difference in the limbic striatum brings into question the therapeutic relevance of the mesolimbic selectivity of second-generation antipsychotic drugs.
Archives of general psychiatry 03/2010; 67(3):231-9. · 12.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent studies in rodents have suggested a role for the central endocannabinoid system in the regulation of mood and alcohol related behaviors. Alcohol use disorder is often associated with suicidal behavior. In the present study, we examined whether abnormalities in the endocannabinoid system in the ventral striatum are associated with alcohol dependence and suicide. The levels of CB1 receptors, receptor-mediated G-protein signaling, and activity and level of the fatty acid amide hydrolase (FAAH) were analyzed postmortem in the ventral striatum of alcohol-dependent nonsuicides (CA, n=9), alcohol-dependent suicides (AS, n=9) and nonpsychiatric controls (C, n=9). All subjects underwent a psychological autopsy, and toxicological and neuropathological examinations. The levels of the CB1 receptors and the CB1 receptor-mediated G-protein signaling were significantly lower in the ventral striatum of CA compared to the control group. However, these parameters were elevated in AS when compared to CA group. The activity of FAAH enzyme was lower in CA compared to the control group while it was found to be significantly higher in AS compared with CA group. These findings suggest that alcohol dependence is associated with the downregulation of the CB1 receptors, while suicide is linked to the upregulation of these receptors in the ventral striatum. Alteration in the activity of FAAH enzyme that regulates the anandamide (AEA) content might in turn explain differences in the CB1 receptor function in alcohol dependence and suicide. These findings may have etiological and therapeutic implications for the treatment of alcohol addiction and suicidal behavior.
Journal of Psychiatric Research 12/2009; 44(9):591-7. · 4.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neurogenesis is a mechanism through which antidepressants may produce therapeutic effects. There is a dearth of information regarding the effects of antidepressants on neurogenesis and neurotrophin mobilization in females. This study examined sex differences in the alteration of cell proliferation and survival in multiple regions of the brain. Additional experiments examined brain-derived neurotrophic factor (BDNF) levels and pharmacokinetics of fluoxetine to determine whether they mediate sex differences. MRL/MpJ mice were treated with fluoxetine (5 and 10 mg/kg b.i.d.) for 21 days and received injections of 5-bromo-2'-deoxyuridine (200 mg/kg) to measure DNA synthesis. In the hippocampus, fluoxetine increased cell proliferation at both doses; females treated with 10 mg/kg produced more new cells than males. Fluoxetine did not alter survival in males, but 10 mg/kg reduced survival in females. In the frontal cortex, fluoxetine increased cell proliferation and survival in males treated with 10 mg/kg. In the cerebellum and amygdala, 10 mg/kg fluoxetine increased cell proliferation in both sexes but did not alter the incorporation of the new cells. Fluoxetine increased BDNF levels in the hippocampus of both sexes. BDNF levels correlated with cell proliferation in males but not females. Brain and plasma levels indicated that females metabolized fluoxetine faster than males and produced more of the metabolite norfluoxetine. These data suggest that fluoxetine acts on multiple areas of the brain to increase cell proliferation, and the pattern of activation differs between males and females. Sex-specific effects of fluoxetine on neurotrophin mobilization and pharmacokinetics may contribute to these differences in neural plasticity.
Journal of Pharmacology and Experimental Therapeutics 10/2009; 332(1):266-73. · 3.89 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Medication resistance is the leading indication for use of electroconvulsive therapy (ECT) in major depression. The practice of stopping antidepressant medications prior to ECT derived from studies in the 1960s and 1970s in nonresistant samples. There is also continuing controversy regarding the relative efficacy and adverse effects of right unilateral and bilateral ECT.
To test the hypotheses that, compared with placebo, concomitant treatment with nortriptline or venlafaxine during the ECT course enhances short-term efficacy without a meaningful effect on adverse effects and reduces the rate of post-ECT relapse, and to test the hypotheses that high-dose, right-sided, unilateral ECT is equivalent in efficacy to moderate-dosage bilateral ECT and retains advantages with respect to cognitive adverse effects.
Prospective, randomized, triple-masked, placebo-controlled study conducted from 2001 through 2005.
Three university-based hospitals.
Of approximately 750 consecutive patients referred for ECT, 319 with a major depressive episode consented, were randomized to pharmacological or ECT treatment conditions, and received at least 1 ECT treatment.
Scores on the Hamilton Rating Scale for Depression, remission rate following completion of ECT, and selective measures of cognitive adverse effects.
Treatment with nortriptyline enhanced the efficacy and reduced the cognitive adverse effects of ECT relative to placebo. Venlafaxine resulted in a weaker degree of improvement and tended to worsen cognitive adverse effects. High-dosage right unilateral ECT did not differ or was superior to bilateral ECT in efficacy and resulted in less severe amnesia.
The efficacy of ECT is substantially increased by the addition of an antidepressant medication, but such medications may differ in whether they reduce or increase cognitive adverse effects. High-dose, right-sided, unilateral ECT is at least equivalent to moderate-dosage bilateral ECT in efficacy, but retains advantages with respect to cognitive adverse effects.
Archives of general psychiatry 08/2009; 66(7):729-37. · 12.26 Impact Factor