Therapeutic Effects of Tamsulosin in Nightmare Disorder: A Randomized, Double Blind, Placebo-Controlled, Cross-Over, Pilot Study

Nightmare disorder is associated with functional impairment, distress, and low quality of life; however, studies on pharmacotherapy of this debilitating disorder yielded mixed results. Prazosin, a non-selective α1 blocker is reported to be effective in treatment of post-traumatic stress disorder-related nightmares. We aimed at investigating therapeutic effects of tamsulosin which has higher affinity for blocking α1A and α1D adrenoceptors in treatment of nightmare disorder. A randomized, double blind, cross-over, placebo-controlled pilot study was conducted. Patients were randomly assigned to receive Tamsulosin 0.4 mg once daily or placebo for period of four weeks. Following a 2-week wash-out period, they were crossed over to the other group and received drug or placebo for duration of 4 additional weeks. Nightmare frequency and intensity measurements were carried out using Disturbing Dreams and Nightmares Severity Index (DDNSI). Blood pressure measurements were also performed. According to per protocol analysis, mean DDNSI scores decreased following administration of tamsulosin and a statistical trend towards significance was reported (p=0.065, d=0.236). Results of intention to treat analysis showed significant difference in DDNSI scores after drug use (p=0.030, d=0.651). Additionally, DDNSI scores dropped significantly following placebo use. However, intention to treat analysis showed no statistically significant difference pre and post placebo period (0.064, d=0.040). Tamsulosin may be effective in treatment of nightmare disorder. However, further larger clinical trials are recommended to clarify the effectiveness of tamsulosin and α1 subtypes in pharmacotherapy of nightmares.

Diosgenin normalization of disrupted behavioral and central neurochemical activity after single prolonged stress

Introduction: Post-traumatic stress disorder (PTSD) is a chronic mental illness triggered by traumatic experiences such as wars, natural disasters, or catastrophes, and it is characterized by anxiety, depression and cognitive impairment. Diosgenin is a steroidal sapogenin with known neuroprotective and antioxidant properties. This study aimed to assess the pharmacological potential of diosgenin in a single prolonged stress (SPS) model of PTSD, plus other behavioral models along with any consequent alterations in brain neurochemistry in male mice. Methodology: SPS was induced by restraining animals for 2 h, followed by 20 min of forced swim, recuperation for 15 min, and finally, exposure to ether to induce anesthesia. The SPS-exposed animals were treated with diosgenin (20, 40, and 60 mg/kg) and compared with the positive controls, fluoxetine or donepezil, then they were observed for any changes in anxiety/depression-like behaviors, and cognitive impairment. After behavioral screening, postmortem serotonin, noradrenaline, dopamine, vitamin C, adenosine and its metabolites inosine and hypoxanthine were quantified in the frontal cortex, hippocampus, and striatum by high-performance liquid chromatography. Additionally, animal serum was screened for changes in corticosterone levels. Results: The results showed that diosgenin reversed anxiety- and depression-like behaviors, and ameliorated cognitive impairment in a dose-dependent manner. Additionally, diosgenin restored monoamine and vitamin C levels dose-dependently and modulated adenosine and its metabolites in the brain regions. Diosgenin also reinstated otherwise increased serum corticosterone levels in SPS mice. Conclusion: The findings suggest that diosgenin may be a potential candidate for improving symptoms of PTSD.

Doxazosin improved COVID-19 associated nightmare in a patient with major depressive disorder: a case report with a positive rechallenge

This article reports on the treatment of a patient with nightmares who was treated with doxazosin of an alpha 1-adrenergic antagonists. A 71-year-old Japanese major depressive disorder (MDD) woman experienced nightmares after the coronavirus disease 2019 pandemic. She had nightmares about being chased by a coronavirus and catching the corona virus. After adding doxazosin 1 mg daily in the morning, her nightmares led to remission without side effects. We also had a rechallenge regimen with doxazosin. The nightmares ceased on the second night of the rechallenge and did not return with continued treatment. This case report suggests that doxazosin may be a useful therapeutic option to target nightmares in individuals with MDD.

α1-Adrenergic Receptors in Neurotransmission, Synaptic Plasticity, and Cognition

α₁-adrenergic receptors are G-Protein Coupled Receptors that are involved in neurotransmission and regulate the sympathetic nervous system through binding and activating the neurotransmitter, norepinephrine, and the neurohormone, epinephrine. There are three α₁-adrenergic receptor subtypes (α_1A, α_1B, α_1D) that are known to play various roles in neurotransmission and cognition. They are related to two other adrenergic receptor families that also bind norepinephrine and epinephrine, the β- and α₂-, each with three subtypes (β₁, β₂, β₃, α_2A, α_2B, α_2C). Previous studies assessing the roles of α₁-adrenergic receptors in neurotransmission and cognition have been inconsistent. This was due to the use of poorly-selective ligands and many of these studies were published before the characterization of the cloned receptor subtypes and the subsequent development of animal models. With the availability of more-selective ligands and the development of animal models, a clearer picture of their role in cognition and neurotransmission can be assessed. In this review, we highlight the significant role that the α₁-adrenergic receptor plays in regulating synaptic efficacy, both short and long-term synaptic plasticity, and its regulation of different types of memory. We will also present evidence that the α₁-adrenergic receptors, and particularly the α_1A-adrenergic receptor subtype, are a potentially good target to treat a wide variety of neurological conditions with diminished cognition.

Evaluation of the Effect of Prazosin Treatment on α-2c Adrenoceptor and Apoptosis Protein Levels in the Predator Scent-Induced Rat Model of Post-Traumatic Stress Disorder

The predator scent-induced (PSI) stress model is a rat model used to mimic post-traumatic stress disorder (PTSD) symptoms in humans. There is growing evidence that prazosin, which blocks α-1 and is approved by the FDA as an anti-hypertensive drug, can potentially be of use in the treatment of PTSD-related sleep disorders. The aim of this study was to investigate the role of prazosin treatment on behavioral parameters (freezing time, total transitions, and rearing frequency measured from the open field; anxiety index, total entries and time spent in open arms calculated from the elevated plus maze), apoptotic proteins and α-2c-AR in fear memory reconsolidation in the PSI stress rat model. We used western blot analysis to determine the effect of prazosin (0.5 mg/kg/ip) on α-2c-AR and apoptotic protein expression changes in the frontal cortex, hippocampus, and amygdala. It was determined that in the stress group, there was increased freezing time and anxiety index, and decreased rearing frequency, total transitions, total entries, and time spent in open arms compared to the control groups. Following PSI-stress, pro-apoptotic (bax) protein expression levels increased and α-2c AR and anti-apoptotic protein (bcl-2) levels decreased in investigated all brain regions. The majority of stress-induced changes were recovered with prazosin treatment. The results of our study may potentially be useful in understanding the effect of prazosin treatment, given the fact that the amygdala, frontal cortex, and hippocampus regions are affected for stress conditions.

Treatment of sleep disturbances in refugees suffering from post-traumatic stress disorder

Sleep disturbances are often referred to as the hallmark of Post-Traumatic Stress Disorder (PTSD). Although PTSD is prevalent in refugees, studies on sleep disturbances in trauma-affected refugees are scarce. This article presents the results of two studies: a systematic review of the literature on treatment of sleep disturbances in adult trauma-affected refugees and a study of the role of sleep disturbances in the PTSD symptom structure. Study 1, the literature review, identified five studies on treatment of sleep disturbances: four studies were on pharmacological treatment and one study on music therapy. The identified studies had small sample sizes and few carried out statistical analysis. It was not possible from the available literature to recommend any specific treatment of sleep disturbances. In Study 2, a clinical sample of 752 refugees, fulfilling criteria for PTSD and enrolled in treatment at the Competence Centre for Transcultural Psychiatry, Denmark, completed the Harvard Trauma Questionnaire (HTQ) before and after treatment. To determine item discrimination, the data was tested with a Rasch model. 99.1% reported trouble sleeping and 98.7% reported recurrent nightmares. The Rasch analysis displayed fit residuals of 0.05 for trouble sleeping and -1.16 for nightmares, indicating sufficient discrimination. Trouble sleeping and nightmares proved important parts of the HTQ response structure. This study indicates that sleep disturbances are a prominent part of the PTSD symptom structure in refugees but that research on treatment of sleep disturbances is limited. Further research on sleep disturbances in trauma-affected refugees is therefore needed.

Cyr K, Nelson C, Sareen J, Elhai J, Zamorski M. Insomnia, psychiatric disorders and suicidal ideation in a National Representative Sample of active Canadian Forces members

BACKGROUND

Past research on the association between insomnia and suicidal ideation (SI) has produced mixed findings. The current study explored the relationship between insomnia, SI, and past-year mental health status among a large Canadian Forces (CF) sample.

METHOD

Data was obtained from the 2013 Canadian Forces Mental Health Survey (CFMHS), and included a large representative sample of Canadian Regular Forces personnel (N = 6700). A series of univariate logistic regressions were conducted to test individual associations between past-year mental health status, insomnia, and potential confounds and SI. Mental health status included three groups: 0, 1, or two or more probable diagnoses of posttraumatic stress disorder (PTSD), major depressive disorder (MDD), generalized anxiety disorder (GAD), panic disorder (PD) and alcohol abuse/dependence. Stepwise multivariate logistic regression was used to assess the relationship between insomnia and SI with mental health status as a moderator.

RESULTS

40.8% of respondents reported experiencing insomnia. Both insomnia and number of mental health conditions incrementally increased the risk of SI. However, past-year mental health status was a significant moderator of this relationship, such that for CF personnel with either no (AOR = 1.61, 1.37-1.89) or only one past-year mental health condition (AOR = 1.39, 1.12-1.73), an incremental increase in insomnia was associated with an increased likelihood of SI. However, in personnel with two or more past-year mental health disorders, insomnia was no longer significantly associated with SI (AOR = 1.04, 0.81-1.33).

CONCLUSIONS

Insomnia significantly increased the odds of SI, but only among individuals with no or one mental health condition. Findings highlight the importance of assessing insomnia among CF members in order to further suicide prevention efforts.

Treatment-refractory posttraumatic stress disorder (TRPTSD): a review and framework for the future

Post-traumatic stress disorder (PTSD) is a serious psychiatric consequence of trauma that occurs in a proportion of individuals exposed to life-threatening events. Trauma-focused psychotherapy is often recommended as first choice for those who do not recover spontaneously. But many individuals require medications. In the US, only paroxetine (PRX) and sertraline (SRT) are FDA approved for PTSD. But response and remission rates with these medications are low, so numerous other pharmacologic interventions have been tried. To date, there has not been a systematic review of the data on what are the best next-step pharmacologic strategies for individuals who fail standard treatments. To that end, we review 168 published trials of medications other than PRX or SRT and provide a detailed analysis of the 88/168 studies that describe alternative pharmacologic interventions in patients refractory to other treatment. We also review clinical factors relevant to treatment-refractory PTSD; the neurobiology of extinction, as well as evidence-based psychotherapy and neuromodulation strategies for this condition.

Amelioration of oxidative stress-induced phenotype loss of parvalbumin interneurons might contribute to the beneficial effects of environmental enrichment in a rat model of post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a common psychiatric disease following exposure to a severe traumatic event or physiological stress, which is characterized by anxiety- and depression-like behaviors and cognitive impairment. However, the underlying mechanisms remain elusive. Parvalbumin (PV) interneurons that are susceptible to oxidative stress are a subset of inhibitory GABAergic neurons regulating the excitability of pyramidal neurons, while dysfunction of PV interneurons is casually linked to many mental disorders including PTSD. We therefore hypothesized that environmental enrichment (EE), a method of enhanced cognitive, sensory and motor stimulation, can reverse the behavioral impairments by normalizing PV interneurons in a rat model of PTSD induced by inescapable foot shocks (IFS). Behavioral changes were determined by the open field, elevated plus maze, fear conditioning, and Morris water maze tests. The levels of nicotinamide adenosine dinucleotide phosphate (NADPH) oxidase 2 (NOX2), NOX4, PV, glutamic acid decarboxylase 67 (GAD-67), and 8-hydroxy-2-deoxyguanosine (8-OH-dG) in the hippocampus and prefrontal cortex were determined. Our results showed that in this PTSD model, rats displayed the anxiety-like behavior, enhanced fear learning behavior, and hippocampus- dependent spatial memory deficit, which were accompanied by the up-regulation of NOX2, 8-OH-dG, and down-regulation of PV and GAD-67. Notably, EE reversed all these abnormalities. These results suggest that restoration of PV interneurons by inhibiting oxidative stress in the hippocampus and prefrontal cortex might represent a mechanism through which EE reverses the behavioral impairments in a rat model of PTSD induced by IFS.

Selective α1-adrenergic blockade disturbs the regional distribution of cerebral blood flow during static handgrip exercise

Handgrip-induced increases in blood flow through the contralateral artery that supplies the cortical representation of the arm have been hypothesized as a consequence of neurovascular coupling and a resultant metabolic attenuation of sympathetic cerebral vasoconstriction. In contrast, sympathetic restraint, in theory, inhibits changes in perfusion of the cerebral ipsilateral blood vessels. To confirm whether sympathetic nerve activity modulates cerebral blood flow distribution during static handgrip (SHG) exercise, beat-to-beat contra- and ipsilateral internal carotid artery blood flow (ICA; Doppler) and mean arterial pressure (MAP; Finometer) were simultaneously assessed in nine healthy men (27 ± 5 yr), both at rest and during a 2-min SHG bout (30% maximal voluntary contraction), under two experimental conditions: 1) control and 2) α1-adrenergic receptor blockade. End-tidal carbon dioxide (rebreathing system) was clamped throughout the study. SHG induced increases in MAP (+31.4 ± 10.7 mmHg, P < 0.05) and contralateral ICA blood flow (+80.9 ± 62.5 ml/min, P < 0.05), while no changes were observed in the ipsilateral vessel (−9.8 ± 39.3 ml/min, P > 0.05). The reduction in ipsilateral ICA vascular conductance (VC) was greater compared with contralateral ICA (contralateral: −0.8 ± 0.8 vs. ipsilateral: −2.6 ± 1.3 ml·min−1·mmHg−1, P < 0.05). Prazosin was effective to induce α1-blockade since phenylephrine-induced increases in MAP were greatly reduced ( P < 0.05). Under α1-adrenergic receptor blockade, SHG evoked smaller MAP responses (+19.4 ± 9.2, P < 0.05) but similar increases in ICAs blood flow (contralateral: +58.4 ± 21.5 vs. ipsilateral: +54.3 ± 46.2 ml/min, P > 0.05) and decreases in VC (contralateral: −0.4 ± 0.7 vs. ipsilateral: −0.4 ± 1.0 ml·min−1·mmHg−1, P > 0.05). These findings indicate a role of sympathetic nerve activity in the regulation of cerebral blood flow distribution during SHG.

Terazosin for the treatment of trauma-related nightmares: a report of 4 cases

The selective α1-adrenergic antagonist prazosin has been shown in multiple studies to be effective in targeting trauma-related nightmares in posttraumatic stress disorder. There are limited data regarding the effectiveness of another selective α1-adrenergic antagonist terazosin for the treatment of trauma-related nightmares. We present 4 cases in which terazosin was effectively used to treat nightmares as a second-line agent after prazosin failure. Further studies are needed to validate terazosin as an alternative to prazosin for the treatment of posttraumatic stress disorder-related nightmares.

Sleep disturbances and suicidal ideation in a sample of treatment-seeking Canadian Forces members and veterans

This study examines the association between suicidal ideation and sleep disturbances in a sample of treatment-seeking Canadian Forces members and veterans, after controlling for probable posttraumatic stress disorder (PTSD), major depressive disorder (MDD), generalised anxiety disorder (GAD), and alcohol use disorder (AUD). Subjects included members and veterans of Canadian Forces seeking treatment at a hospital-based Operational Stress Injury Clinic (n=404). Sleep disturbances and nightmares were measured using individual items on the PTSD Checklist - Military Version (PCL - M), while the suicidality item of the Patient Health Questionnaire (PHQ-9) was used as a stand-alone item to assess presence or absence of suicidal ideation. Regression analyses were used to determine the respective impact of (1) insomnia and (2) nightmares on suicidal ideation, while controlling for presence of probable PTSD, MDD, GAD, and AUD. We found that 86.9% of patients reported having problems falling or staying asleep and 67.9% of patients reported being bothered by nightmares related to military-specific traumatic events. Neither sleep disturbances nor nightmares significantly predicted suicidal ideation; instead, probable MDD emerged as the most significant predictor. The clinical implications of these findings and their potential impact on treatment guidelines are discussed.

Effects of L-theanine on posttraumatic stress disorder induced changes in rat brain gene expression

Posttraumatic stress disorder (PTSD) is characterized by the occurrence of a traumatic event that is beyond the normal range of human experience. The future of PTSD treatment may specifically target the molecular mechanisms of PTSD. In the US, approximately 20% of adults report taking herbal products to treat medical illnesses. L-theanine is the amino acid in green tea primarily responsible for relaxation effects. No studies have evaluated the potential therapeutic properties of herbal medications on gene expression in PTSD. We evaluated gene expression in PTSD-induced changes in the amygdala and hippocampus of Sprague-Dawley rats. The rats were assigned to PTSD-stressed and nonstressed groups that received either saline, midazolam, L-theanine, or L-theanine + midazolam. Amygdala and hippocampus tissue samples were analyzed for changes in gene expression. One-way ANOVA was used to detect significant difference between groups in the amygdala and hippocampus. Of 88 genes examined, 17 had a large effect size greater than 0.138. Of these, 3 genes in the hippocampus and 5 genes in the amygdala were considered significant (P < 0.05) between the groups. RT-PCR analysis revealed significant changes between groups in several genes implicated in a variety of disorders ranging from PTSD, anxiety, mood disorders, and substance dependence.

Current status on behavioral and biological markers of PTSD: a search for clarity in a conflicting literature

Extensive research has identified stereotypic behavioral and biological abnormalities in post-traumatic stress disorder (PTSD), such as heightened autonomic activity, an exaggerated startle response, reduced basal cortisol levels and cognitive impairments. We have reviewed primary research in this area, noting that factors involved in the susceptibility and expression of PTSD symptoms are more complex and heterogeneous than is commonly stated, with extensive findings which are inconsistent with the stereotypic behavioral and biological profile of the PTSD patient. A thorough assessment of the literature indicates that interactions among myriad susceptibility factors, including social support, early life stress, sex, age, peri- and post-traumatic dissociation, cognitive appraisal of trauma, neuroendocrine abnormalities and gene polymorphisms, in conjunction with the inconsistent expression of the disorder across studies, confounds attempts to characterize PTSD as a monolithic disorder. Overall, our assessment of the literature addresses the great challenge in developing a behavioral and biomarker-based diagnosis of PTSD.

Prazosin treatment of nightmares related to post-traumatic stress disorder

This case demonstrates the efficacy of prazosin in treating civilian post traumatic stress disorder (PTSD)-related nightmares. Although its mechanism is not fully elucidated, it is clear that prazosin decreases nightmares. Tolerability may limit one's ability to titrate to an effective dose.

Re-emergence of posttraumatic stress disorder nightmares with nursing home admission: treatment with prazosin

Seniors with a history of emotional trauma decades earlier can experience a recurrence of posttraumatic stress disorder symptoms when transitioning to a nursing home. We present the case of an 86-year-old male Holocaust survivor admitted to a nursing home for physical therapy and rehabilitation 6 weeks after the death of his wife; the patient was expressing a persistent death wish. Despite the multiple risk factors for depression, his distress was specifically related to the reemergence of nightly posttraumatic nightmares. Over the course of 1 week of treatment with 1 mg prazosin at bedtime, his nightmares and his death wish completely resolved. He achieved his rehabilitation goals and was discharged to a community setting. This report highlights the importance of considering posttraumatic stress disorder in nursing home residents with a history of emotional trauma, and understanding how to address these symptoms pharmacologically and nonpharmacologically.

Treatment of nightmares with prazosin: a systematic review

Nightmares, frequently associated with posttraumatic stress disorder and clinically relevant in today's world of violence, are difficult to treat, with few pharmacologic options. We performed a systematic review to evaluate the evidence for the use of prazosin in the treatment of nightmares. A comprehensive search was performed using the databases EMBASE, Ovid MEDLINE, PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews, from their inception to March 9, 2012, using keywords prazosin and nightmares/PTSD or associated terms (see text). Two authors independently reviewed titles and abstracts and selected relevant studies. Descriptive data and outcomes of interest from eligible studies were extracted by 1 author, and checked by 2 others. The risk of bias of randomized controlled trials (RCTs) was assessed independently by 2 reviewers. Articles met criteria for inclusion if prazosin was used to treat nightmares, and outcome measures included nightmares or related symptoms of sleep disorders. Our search yielded 21 studies, consisting of 4 RCTs, 4 open-label studies, 4 retrospective chart reviews, and 9 single case reports. The prazosin dose ranged from 1 to 16 mg/d. Results were mixed for the 4 RCTs: 3 reported significant improvement in the number of nightmares, and 1 found no reduction in the number of nightmares. Reduced nightmare severity with use of prazosin was consistently reported in the open-label trials, retrospective chart reviews, and single case reports.

Retrospective cross-validation of automated sleep staging using electroocular recording in patients with and without sleep disordered breathing

BACKGROUND

Alterations of sleep duration and architecture have been associated with increased morbidity and mortality, and specifically linked to chronic cardiovascular disease and psychiatric disorders, such as type 2 diabetes or depression. Measurement of sleep quality to assist in the diagnosis or treatment of these diseases is not routinely performed due to the complexity and cost of conventional methods. The objective of this study is to cross-validate the accuracy of an automated algorithm that stages sleep from the EEG signal acquired with sensors that can be self-applied by patients.

METHODS

This retrospective study design included polymsomnographic records from 19 presumably healthy individuals and 68 patients suspected of having sleep disordered breathing (SDB). Epoch-by-epoch comparisons were made between manual vs. automated sleeps staging (from the left and right electrooculogram) with the impact of SDB severity considered.

RESULTS

Both scoring methods reported decreased Stage N3 and REM and increased wake and N1 as SDB severity increased. Inter-class correlations and Kappa coefficients were strong across all stages except N1. Agreements across all epochs for subjects with normal and patients with mild SDB were: wake = 80%, N1 = 25%, N2 = 78%, N3 = 84% and REM = 75%. Agreement decreased in patients with moderate and severe SDB amounting to: wake = 71%, N1 = 30%, N2 = 71%, N3 = 65%, and REM = 67%. Differences in detection of sleep onset were within three-minutes in 48 % of the subjects and 10-min in 73 % of the cases and were not impacted by SDB severity. Automated staging slightly underestimated total sleep time but this difference had a limited impact on the respiratory disturbance indexes.

CONCLUSIONS

This cross-validation study demonstrated that measurement of sleep architecture obtained from a single-channel of forehead EEG can be equivalent to between-rater agreement using conventional manual scoring. The accuracies obtained with automated sleep staging were inversely proportional to SDB severity at a rate similar to manual scorers. These results suggest that the automated sleep staging used in this study may prove useful in evaluating sleep quality in patients with chronic diseases.

Prazosin for the treatment of nightmares related to posttraumatic stress disorder: a review of the literature

BACKGROUND

Posttraumatic stress disorder (PTSD) is a psychiatric disorder with symptoms that include insomnia due to hyperarousal and recurring nightmares. These symptoms are believed to be due to a conditioned response that is regulated by norepinephrine. Prazosin, an α(1) antagonist, can decrease levels of norepinephrine in the central nervous system, thereby reducing nightmares related to PTSD.

DATA SOURCES

A literature search was conducted for all studies evaluating the effectiveness of prazosin as therapy for nightmare symptoms of PTSD. MEDLINE was utilized to identify all English-language studies published between 1966 and March 2011. Keywords searched included prazosin, PTSD, and nightmares.

RESULTS

Eleven studies were identified, including 4 open-label trials, 4 retrospective chart reviews, and 3 placebo-controlled trials. Prazosin demonstrated favorable clinical efficacy and was found to be safe for relieving PTSD-associated nightmares.

CONCLUSIONS

Current data indicate that prazosin is an effective agent for the treatment of nightmares associated with PTSD. However, the data are limited by small study sizes, lack of diversified investigators, and lack of regional diversity.

Pharmacotherapeutics directed at deficiencies associated with cocaine dependence: focus on dopamine, norepinephrine and glutamate

Much effort has been devoted to research focused on pharmacotherapies for cocaine dependence yet there are no FDA-approved medications for this brain disease. Preclinical models have been essential to defining the central and peripheral effects produced by cocaine. Recent evidence suggests that cocaine exerts its reinforcing effects by acting on multiple neurotransmitter systems within mesocorticolimibic circuitry. Imaging studies in cocaine-dependent individuals have identified deficiencies in dopaminergic signaling primarily localized to corticolimbic areas. In addition to dysregulated striatal dopamine, norepinephrine and glutamate are also altered in cocaine dependence. In this review, we present these brain abnormalities as therapeutic targets for the treatment of cocaine dependence. We then survey promising medications that exert their therapeutic effects by presumably ameliorating these brain deficiencies. Correcting neurochemical deficits in cocaine-dependent individuals improves memory and impulse control, and reduces drug craving that may decrease cocaine use. We hypothesize that using medications aimed at reversing known neurochemical imbalances is likely to be more productive than current approaches. This view is also consistent with treatment paradigms used in neuropsychiatry and general medicine.

Treating nightmares and insomnia in posttraumatic stress disorder: a review of current evidence

Emerging evidence supports the notion of disrupted sleep as a core component of Posttraumatic Stress Disorder (PTSD). Effective treatments for nighttime PTSD symptoms are critical because sleep disruption may be mechanistically linked to development and maintenance of PTSD and is associated with significant distress, functional impairment, and poor health. This review aimed to describe the state of science with respect to the impact of the latest behavioral and pharmacological interventions on posttraumatic nightmares and insomnia. Published studies that examined evidence for therapeutic effects upon sleep were included. Some behavioral and pharmacological interventions show promise, especially for nightmares, but there is a need for controlled trials that include valid sleep measures and are designed to identify treatment mechanisms. Our ability to treat PTSD-related sleep disturbances may be improved by moving away from considering sleep symptoms in isolation and instead conducting integrative studies that examine sequential or combined behavioral and/or pharmacological treatments targeting both the daytime and nighttime aspects of PTSD. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

Treatment options for parasomnias

Parasomnias are undesirable physical or experiential events that occur in and around sleep. Treatments include reassurance in some cases, various forms of cognitive-behavioral therapy (CBT), and pharmacologic agents. Cognitive restructuring, imagery rehearsal, relaxation, hypnosis, desensitization, and anticipatory awakenings are some of the common CBT and nonpharmacologic interventions. Medications that are used belong to a wide variety of pharmacologic classes, such as alpha-blockers (prazosin), tricyclic antidepressants (imipramine and clomipramine), selective serotonin reuptake inhibitors, benzodiazepines (diazepam and clonazepam), anticonvulsants (topiramate and gabapentin), desmopressin acetate, and anticholinergic agents (oxybutynin and tolterodine). Data on efficacy are only available from randomized trials on CBT and prazosin for nightmares and on pharmacologic and alarm therapy for enuresis. No large-scale randomized trials are available to assess the efficacy of the other treatments, and most data come from anecdotal case reports, case series, or small open-label trials.

Effects of modafinil and prazosin on cognitive and physiological functions in healthy volunteers

Previous research has demonstrated cognitive-enhancing effects of modafinil in humans and generated evidence for its therapeutic potential in psychiatric disorders. The neurochemical basis of these effects remains unresolved although a role for α1-adrenoceptors has been hypothesised. In this within-subject, double-blind, placebo-controlled study, 12 healthy male adults received modafinil (300 mg), the α1-adrenoceptor antagonist prazosin (3 mg), both together and placebo on separate occasions at least 5 days apart. Cognitive effects were assessed using a well-validated testing battery focusing on executive and working memory functions. Blood pressure, heart rate and salivary α-amylase (sAA) were measured at hourly intervals. Cognitive effects of modafinil and prazosin were identified at the difficult levels of the One-Touch Stockings of Cambridge (OTSOC) planning task. Prazosin antagonized the error-reducing effect of modafinil when the agents were given together. In contrast, the combined agents acted synergistically to increase time taken to complete OTSOC problems compared with placebo. The tachycardic and sAA-elevating effects of prazosin were also potentiated by concurrent modafinil administration. The current data suggest that the cognitive effects of modafinil on performance accuracy and latency are dissociable in terms of their neurochemical mechanisms. Our findings support the hypothesised involvement of α1-adrenoceptors in some of the cognitive-enhancing effects of modafinil and warrant further investigation.

Sleep in psychiatric disorders: where are we now?

Although the precise function of sleep is unknown, decades of research strongly implicate that sleep has a vital role in central nervous system (CNS) restoration, memory consolidation, and affect regulation. Slow-wave sleep (SWS) and rapid eye movement (REM) sleep have been of significant interest to psychiatrists; SWS because of its putative role in CNS energy recuperation and cognitive function, and REM sleep because of its suggested involvement in memory, mood regulation, and possible emotional adaptation. With the advent of the polysomnogram, researchers are now beginning to understand some of the consequences of disrupted sleep and sleep deprivation in psychiatric disorders. The same neurochemistry that controls the sleep-wake cycle has also been implicated in the pathophysiology of numerous psychiatric disorders. Thus it is no surprise that several psychiatric disorders have prominent sleep symptoms. This review will summarize normal sleep architecture, and then examine sleep abnormalities and comorbid sleep disorders seen in schizophrenia, as well as anxiety, cognitive, and substance abuse disorders.

A role for alpha-adrenergic receptors in extinction of conditioned fear and cocaine conditioned place preference

Previous work has demonstrated an important role for adrenergic receptors in memory processes in fear and drug conditioning paradigms. Recent studies have also demonstrated alterations in extinction in these paradigms using drug treatments targeting beta- and alpha2-adrenergic receptors, but little is known about the role of alpha-adrenergic receptors in extinction. The current study examined whether antagonism of alpha-adrenergic receptors would impair the consolidation of extinction in fear and cocaine conditioned place preference paradigms. After contextual fear conditioning, injections of the alpha-adrenergic receptor antagonist prazosin (1.0 or 3.0 mg/kg) following nonreinforced context exposures slowed the loss of conditioned freezing over the course of 5 extinction sessions (Experiment 1). After cocaine place conditioning, prazosin had no effect on the rate of extinction over 8 nonreinforced test sessions. Following postextinction reconditioning, however, prazosin-treated mice showed a robust place preference, but vehicle-treated mice did not, suggesting that prazosin reduced the persistent effects of extinction (Experiment 2). These results confirm the involvement of the alpha-adrenergic receptor in extinction processes in both appetitive and aversive preparations.