piperidines and Stress-Disorders--Post-Traumatic

Several lines of evidence suggest that glutamatergic neurotransmission via the N-methyl-D-aspartate (NMDA) receptor plays a role in certain behavioral manifestations common to Post-Traumatic Stress Disorder (PTSD). Ifenprodil tartrate is a neuroprotective agent that binds to the GluN2B subunit of the NMDA receptor. The aim of this study is to confirm whether ifenprodil tartrate is effective in the adolescent PTSD patients.. This is a randomized, double-blind, placebo-controlled trial. Ten adolescent (13 to 18 years old) PTSD patients were randomized into two arms: placebo (n = 4), 40 mg/day ifenprodil tartrate (n = 6) for 4 weeks. All of the patients were assessed by IES-R-J (Primary outcome measure), TSCC-J, CDRS-R, DSRS-C-J and CGI-I.. A comparison of baseline IES-R-J total scores and 4-week end-point scores showed a mild trend of improvement (p = 0.0895) and the difference score was -9.314. A comparison of baseline scores and 2-week intermediate-point scores showed that IES-R-J hyperarousal subscores and TSCC-J subscores (dissociation subscores, sexual concerns subscores) improved significantly. A comparison of baseline TSCC-J sexual concerns subscores and 4-week end-point scores improved significantly.. Our study may prove to be an short-term effective alternative safe treatment for adolescent patients with PTSD.

Topics: Adolescent; Double-Blind Method; Humans; Piperidines; Stress Disorders, Post-Traumatic; Treatment Outcome

The substance P-neurokinin-1 receptor (SP-NK(1)R) system has been extensively studied in experimental models of stress, fear, and reward. Elevated cerebrospinal fluid (CSF) SP levels were reported previously in combat-related PTSD. No medication specifically targeting this system has been tested in PTSD. This proof-of-concept randomized, double-blind, placebo-controlled trial evaluated the selective NK(1)R antagonist GR205171 in predominately civilian PTSD. Following a 2-week placebo lead-in, 39 outpatients with chronic PTSD and a Clinician-Administered PTSD Scale (CAPS) score ≥50 were randomized to a fixed dose of GR205171 (N=20) or placebo (N=19) for 8weeks. The primary endpoint was mean change from baseline to endpoint in the total CAPS score. Response rate (≥50% reduction in baseline CAPS) and safety/tolerability were secondary endpoints. CSF SP concentrations were measured in a subgroup of patients prior to randomization. There was significant improvement in the mean CAPS total score across all patients over time, but no significant difference was found between GR205171 and placebo. Likewise, there was no significant effect of drug on the proportion of responders [40% GR205171 versus 21% placebo (p=0.30)]. An exploratory analysis showed that GR205171 treatment was associated with significant improvement compared to placebo on the CAPS hyperarousal symptom cluster. GR205171 was well-tolerated, with no discontinuations due to adverse events. CSF SP concentrations were positively correlated with baseline CAPS severity. The selective NK(1)R antagonist GR205171 had fewer adverse effects but was not significantly superior to placebo in the short-term treatment of chronic PTSD. (ClinicalTrials.gov Identifier: NCT 00211861, NCT 00383786).

Topics: Adult; Double-Blind Method; Female; Humans; Male; Middle Aged; Neurokinin-1 Receptor Antagonists; Piperidines; Placebos; Psychiatric Status Rating Scales; Stress Disorders, Post-Traumatic; Substance P; Tetrazoles; Time Factors; Treatment Outcome; Young Adult

1. This study examines the relation between baseline clinical characteristics in patients with posttraumatic stress disorder (PTSD) and response to treatment with a reversible monoamine oxidase A inhibitor (RIMA), brofaromine. 2. Data from two comparable, double-blind, placebo-controlled studies of brofaromine in patients with PTSD were combined. Bivariate analyses of variables of interest and outcome were performed. 3. Treatment response was significantly associated with lower baseline scores on the full scale Clinician-Administered PTSD Scale (CAPS) and on CAPS subscales B (re-experiencing) and C (avoidance/numbing), as well as to drug treatment with brofaromine. Placebo response was related to a history of past sexual trauma. 4. Brofaromine may have therapeutic benefit in treating PTSD, with lower baseline levels of reexperiencing and avoidance/numbing and overall less severe PTSD most predictive of outcome.

Topics: Adult; Age of Onset; Analysis of Variance; Disasters; Double-Blind Method; Female; Humans; Male; Monoamine Oxidase Inhibitors; Piperidines; Placebos; Predictive Value of Tests; Prognosis; Psychological Tests; Sex Offenses; Stress Disorders, Post-Traumatic; Treatment Outcome; United States; Warfare

A large multi-center, double-blind, parallel trial to assess the efficacy of brofaromine in the treatment of post traumatic stress disorder (PTSD) failed to show a significant difference between the brofaromine and placebo treatment groups. The placebo response rate in this study was higher than that in previously published double-blind, placebo-controlled studies of PTSD.

Topics: Adult; Aged; Double-Blind Method; Female; Humans; Male; Middle Aged; Monoamine Oxidase Inhibitors; Piperidines; Stress Disorders, Post-Traumatic

The endocannabinoid (eCB) system is a potential target for the treatment of symptoms of post-traumatic stress disorder (PTSD). Similar to clinical PTSD, approximately 25-30% of rats that undergo cued fear conditioning exhibit impaired extinction learning. In addition to extinction-resistant fear, these "weak extinction" (WE) rats show persistent anxiety-like behaviors. The goal of the present study was to test the hypothesis that behavioural differences between WE animals and those presenting normal extinction patterns (strong extinction; SE) could be mediated by the eCB system. Rats undergoing fear conditioning/extinction and fear recall sessions were initially segregated in weak and strong-extinction groups. Two weeks later, animals underwent a fear recall session followed by a novelty-suppressed feeding (NSF) test. In acute experiments, WE rats were injected with either the fatty acid amide hydrolase (FAAH) inhibitor URB597 or the CB1 agonist WIN55,212-2 1 h prior to long-term recall and NSF testing. SE animals were injected with the inverse CB

Topics: Animals; Anxiety; Benzamides; Benzoxazines; Carbamates; Conditioning, Psychological; Disease Models, Animal; Endocannabinoids; Fear; Male; Morpholines; Naphthalenes; Piperidines; Pyrazoles; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB1; Rodentia; Stress Disorders, Post-Traumatic

Evaluation of pharmacotherapies for acute stress disorder (ASD) or post-traumatic stress disorder (PTSD) is challenging due to robust heterogeneity of trauma histories and limited efficacy of any single candidate to reduce all stress-induced effects. Pursuing novel mechanisms, such as the nociceptin/orphanin FQ (NOP) system, may be a viable path for therapeutic development and of interest as it is involved in regulation of relevant behaviors and recently implicated in PTSD and ASD.. First, we evaluated NOP receptor antagonism on general behavioral performance and again following a three-species predator exposure model (Experiment 1). Then, we evaluated effects of NOP antagonism on fear memory expression (Experiment 2).. Adult, male rats underwent daily administration of NOP antagonists (J-113397 or SB-612,111; 0-20 mg/kg, i.p.) and testing in acoustic startle, elevated plus maze, tail-flick, and open field tests. Effects of acute NOP antagonism on behavioral performance following predator exposure were then assessed. Separately, rats underwent fear conditioning and were later administered SB-612,111 (0-3 mg/kg, i.p.) prior to fear memory expression tests.. J-113397 and SB-612,111 did not significantly alter most general behavioral performance measures alone, suggesting minimal off-target behavioral effects of NOP antagonism. J-113397 and SB-612,111 restored performance in measures of exploratory behavior (basic movements on the elevated plus maze and total distance in the open field) following predator exposure. Additionally, SB-612,111 significantly reduced freezing behavior relative to control groups across repeated fear memory expression tests, suggesting NOP antagonism may be useful in dampening fear responses. Other measures of general behavioral performance were not significantly altered following predator exposure.. NOP antagonists may be useful as pharmacotherapeutics for dampening fear responses to trauma reminders, and the present results provide supporting evidence for the implication of the NOP system in the neuropathophysiology of dysregulations in fear learning and memory processes observed in trauma- and stress-related disorders.

Topics: Animals; Benzimidazoles; Cycloheptanes; Dose-Response Relationship, Drug; Exploratory Behavior; Fear; Male; Memory; Nociceptin; Nociceptin Receptor; Opioid Peptides; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, Opioid; Stress Disorders, Post-Traumatic

Exposure to a traumatic event may result in the development of post-traumatic stress disorder (PTSD). Endocannabinoids are crucial modulators of the stress response, interfere with excessive retrieval and facilitate the extinction of traumatic memories. Exposure therapy, combined with pharmacotherapy, represents a promising tool for PTSD treatment. We investigated whether pharmacological manipulations of the endocannabinoid system during extinction learning ameliorates the behavioral changes induced by trauma exposure. Rats were exposed to inescapable footshocks paired with social isolation, a risk factor for PTSD. One week after trauma, rats were subjected to three spaced extinction sessions, mimicking human exposure therapy. The anandamide hydrolysis inhibitor URB597, the 2-arachidonoylglycerol hydrolysis inhibitor JZL184 or the cannabinoid agonist WIN55,212-2 were administered before or after the extinction sessions. Rats were tested for extinction retention 16 or 36 days after trauma and 24-h later for social interaction. Extinction training alone reduced fear of the trauma-associated context but did not restore normal social interaction. Traumatized animals not exposed to extinction sessions exhibited reductions in hippocampal anandamide content with respect to home-cage controls. Noteworthy, all drugs exerted beneficial effects, but URB597 (0.1 mg/kg) induced the best improvements by enhancing extinction consolidation and restoring normal social behavior in traumatized rats through indirect activation of CB1 receptors. The ameliorating effects remained stable long after treatment and trauma exposure. Our findings suggest that drugs potentiating endocannabinoid neurotransmission may represent promising tools when combined to exposure-based psychotherapies in the treatment of PTSD.

Topics: Amidohydrolases; Animals; Arachidonic Acids; Benzamides; Benzodioxoles; Benzoxazines; Cannabinoid Receptor Modulators; Carbamates; Disease Models, Animal; Electroshock; Endocannabinoids; Extinction, Psychological; Glycerides; Male; Morpholines; Naphthalenes; Piperidines; Psychotropic Drugs; Rats, Sprague-Dawley; Social Isolation; Stress Disorders, Post-Traumatic; Synaptic Transmission

Activating the endocannabinoid system has become a major focus in the search for novel therapeutics for anxiety and deficits in fear extinction, two defining features of PTSD. We examined whether chronic treatment with the fatty acid amide hydrolase (FAAH) inhibitor URB597 (0.2, 0.3, 0.4 mg/kg, i.p.) or the CB1/2 receptor agonist WIN55,212-2 (0.25, 0.5 mg/kg, i.p.) injected for 3 weeks to rats exposed to the shock and reminders model of PTSD would attenuate post-stress symptoms and affect basolateral amygdala (BLA) and CA1 CB1 receptors. Exposure to shock and reminders enhanced acoustic startle response and impaired extinction. Rats exposed to shock and reminders and chronically treated with URB597 demonstrated normalized startle response and intact extinction kinetics. WIN55,212-2 only affected the startle response. The therapeutic effects of URB597 and WIN55,212-2 were found to be CB1 receptor dependent, as these effects were blocked when a low dose of the CB1 receptor antagonist AM251 (0.3 mg/kg, i.p. for 3 weeks) was co-administered. Moreover, URB597, but not WIN55,212-2, normalized the shock/reminders-induced upregulation in CB1 receptor levels in the BLA and CA1. One hour after the shock, N-arachidonoylethanolamine (AEA) was increased in the BLA and decreased in the CA1. Circulating 2-arachidonoylglycerol (2-AG) concentrations were decreased in shocked rats, with no significant effect in the BLA or CA1. FAAH activity was increased in the CA1 of shocked rats. Chronic cannabinoid treatment with URB597 can ameliorate PTSD-like symptoms suggesting FAAH inhibitors as a potentially effective therapeutic strategy for the treatment of disorders associated with inefficient fear coping.

Topics: Amidohydrolases; Animals; Arachidonic Acids; Basolateral Nuclear Complex; Benzamides; Benzoxazines; CA1 Region, Hippocampal; Cannabinoid Receptor Antagonists; Carbamates; Dose-Response Relationship, Drug; Electric Stimulation; Endocannabinoids; Extinction, Psychological; Glycerides; Male; Morpholines; Naphthalenes; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Rats; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Reflex, Startle; Stress Disorders, Post-Traumatic

Exposure to excessive or uncontrolled stress is a major factor associated with various diseases including posttraumatic stress disorder (PTSD). The consequences of exposure to trauma are affected not only by aspects of the event itself, but also by the frequency and severity of trauma reminders. It was suggested that in PTSD, hippocampal-dependent memory is compromised while amygdala-dependent memory is strengthened. Several lines of evidence support the role of the endocannabinoid (eCB) system as a modulator of the stress response. In this study we aimed to examine cannabinoids modulation of the long-term effects (i.e., 1 month) of exposure to a traumatic event on memory and plasticity in the hippocampus and amygdala. Following exposure to the shock and reminders model of PTSD in an inhibitory avoidance light-dark apparatus rats demonstrated: (i) enhanced fear retrieval and impaired inhibitory extinction (Ext), (ii) no long-term potentiation (LTP) in the CA1, (iii) impaired hippocampal-dependent short-term memory in the object location task, (iv) enhanced LTP in the amygdala, and (v) enhanced amygdala-dependent conditioned taste aversion memory. The cannabinoid CB1/2 receptor agonist WIN55-212,2 (0.5mg/kg, i.p.) and the fatty acid amide hydrolase (FAAH) inhibitor URB597 (0.3mg/kg, i.p.), administered 2 hr after shock exposure prevented these opposing effects on hippocampal- and amygdala-dependent processes. Moreover, the effects of WIN55-212,2 and URB597 on Ext and acoustic startle were prevented by co-administration of a low dose of the CB1 receptor antagonist AM251 (0.5mg/kg, i.p.), suggesting that the preventing effects of both drugs are mediated by CB1 receptors. Exposure to shock and reminders increased CB1 receptor levels in the CA1 and basolateral amygdala 1 month after shock exposure and this increase was also prevented by administering WIN55-212,2 or URB597. Taken together, these findings suggest the involvement of the eCB system, and specifically CB1 receptors, in the opposite effects of severe stress on memory and plasticity in the hippocampus and amygdala.

Topics: Amidohydrolases; Amygdala; Animals; Avoidance Learning; Benzamides; Benzoxazines; Bromine; Cannabinoid Receptor Modulators; Cannabinoids; Carbamates; Disease Models, Animal; Drug Combinations; Electroshock; Enzyme Inhibitors; Fear; Glutamates; Hippocampus; Magnesium; Male; Memory; Morpholines; Naphthalenes; Neuronal Plasticity; Piperidines; Pyrazoles; Rats, Sprague-Dawley; Receptors, Cannabinoid; Stress Disorders, Post-Traumatic

The nociceptin/orphanin FQ peptide (NOP) receptor is believed to have an integral modulatory function in the stress response system. We evaluated the highly selective NOP antagonist J-113397 (7.5 and 20.0 mg/kg), using a predator exposure in which rats were exposed to predator cats as a stressor. A single dose of J-113397 or vehicle was administered (intraperitoneally) shortly before exposure to the predators or a sham exposure. Behavioral impact was measured using elevated plus maze (EPM), open field activity (OFA), and an olfactory discrimination (OD). The predator exposure produced a relatively long-lasting deficit (decreased time in open arms, decreased basic activity) on the EPM while having little effect on performance on the OFA or OD. J-113397 mitigated the performance deficits on the EPM in a dose-dependent manner while having little effect on performance on the OFA or OD. The largest dose of J-113397, administered with a sham exposure, was essentially devoid of effects on the EPM, OFA, and OD. These results demonstrate that J-113397 can significantly and selectively mitigate the effects of a stressor typically used in a preclinical model of post-traumatic stress disorder. Furthermore, these results are consistent with and extend previous results showing that the NOP receptor has an important role in the response to stress and that NOP antagonism may, potentially, have therapeutic benefit in stress disorders.

Topics: Animals; Anxiety; Benzimidazoles; Cats; Male; Narcotic Antagonists; Nociceptin; Nociceptin Receptor; Opioid Peptides; Peptide Fragments; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, Opioid; Stress Disorders, Post-Traumatic; Stress, Physiological; Stress, Psychological

The brain serotonergic system is colocalized and interacts with the neuropeptidergic substance P/neurokinin-1 (SP/NK1) system. Both these neurochemical systems have independently been implicated in stress and anxiety, but interactions between them might be crucial for human anxiety conditions. Here, we examined the serotonin and substance P/neurokinin-1 (SP/NK1) systems individually as well as their overlapping expression in 16 patients with posttraumatic stress disorder (PTSD) and 16 healthy controls. Participants were imaged with the highly selective radiotracers [(11)C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile (DASB) and [(11)C]GR205171 assessing serotonin transporter (SERT) and NK1 receptor availability, respectively. Voxel-wise analyses in the amygdala, our a priori-defined region of interest, revealed increased number of NK1 receptors, but not SERT in the PTSD group. Symptom severity, as indexed by the Clinician-administered PTSD Scale, was negatively related to SERT availability in the amygdala, and NK1 receptor levels moderated this relationship. Exploratory, voxel-wise whole-brain analyses revealed increased SERT availability in the precentral gyrus and posterior cingulate cortex of PTSD patients. Patients, relative to controls, displayed lower degree of overlapping expression between SERT and NK1 receptors in the putamen, thalamus, insula and lateral orbitofrontal gyrus, lower overlap being associated with higher PTSD symptom severity. Expression overlap also explained more of the symptomatology than did either system individually, underscoring the importance of taking interactions between the neurochemical systems into account. Thus, our results suggest that aberrant serotonergic-SP/NK1 couplings contribute to the pathophysiology of PTSD and, consequently, that normalization of these couplings may be therapeutically important.

Topics: Adult; Amygdala; Aniline Compounds; Anxiety Disorders; Brain; Case-Control Studies; Cerebral Cortex; Female; Humans; Male; Piperidines; Positron-Emission Tomography; Receptors, Neurokinin-1; Serotonin; Serotonin Plasma Membrane Transport Proteins; Stress Disorders, Post-Traumatic; Substance P; Sulfides; Tetrazoles; Transcriptome

Topics: Adolescent; Child; Child Abuse, Sexual; Excitatory Amino Acid Antagonists; Female; Humans; Piperidines; Stress Disorders, Post-Traumatic

Endocannabinoids and their attending cannabinoid type 1 (CB1) receptor have been implicated in animal models of post-traumatic stress disorder (PTSD). However, their specific role has not been studied in people with PTSD. Herein, we present an in vivo imaging study using positron emission tomography (PET) and the CB1-selective radioligand [(11)C]OMAR in individuals with PTSD, and healthy controls with lifetime histories of trauma (trauma-exposed controls (TC)) and those without such histories (healthy controls (HC)). Untreated individuals with PTSD (N=25) with non-combat trauma histories, and TC (N=12) and HC (N=23) participated in a magnetic resonance imaging scan and a resting PET scan with the CB1 receptor antagonist radiotracer [(11)C]OMAR, which measures the volume of distribution (VT) linearly related to CB1 receptor availability. Peripheral levels of anandamide, 2-arachidonoylglycerol, oleoylethanolamide, palmitoylethanolamide and cortisol were also assessed. In the PTSD group, relative to the HC and TC groups, we found elevated brain-wide [(11)C]OMAR VT values (F(2,53)=7.96, P=0.001; 19.5% and 14.5% higher, respectively), which were most pronounced in women (F(1,53)=5.52, P=0.023). Anandamide concentrations were reduced in the PTSD relative to the TC (53.1% lower) and HC (58.2% lower) groups. Cortisol levels were lower in the PTSD and TC groups relative to the HC group. Three biomarkers examined collectively--OMAR VT, anandamide and cortisol--correctly classified nearly 85% of PTSD cases. These results suggest that abnormal CB1 receptor-mediated anandamide signaling is implicated in the etiology of PTSD, and provide a promising neurobiological model to develop novel, evidence-based pharmacotherapies for this disorder.

Topics: Adult; Amides; Analysis of Variance; Arachidonic Acids; Brain; Endocannabinoids; Ethanolamines; Female; Glycerides; Humans; Hydrocortisone; Imidazoles; Logistic Models; Male; Palmitic Acids; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Radionuclide Imaging; Receptor, Cannabinoid, CB1; Stress Disorders, Post-Traumatic; Young Adult

The amygdala-dependent molecular mechanisms driving the onset and persistence of posttraumatic stress disorder (PTSD) are poorly understood. Recent observational studies have suggested that opioid analgesia in the aftermath of trauma may decrease the development of PTSD. Using a mouse model of dysregulated fear, we found altered expression within the amygdala of the Oprl1 gene (opioid receptor-like 1), which encodes the amygdala nociceptin (NOP)/orphanin FQ receptor (NOP-R). Systemic and central amygdala infusion of SR-8993, a new highly selective NOP-R agonist, impaired fear memory consolidation. In humans, a single-nucleotide polymorphism (SNP) within OPRL1 is associated with a self-reported history of childhood trauma and PTSD symptoms (n = 1847) after a traumatic event. This SNP is also associated with physiological startle measures of fear discrimination and magnetic resonance imaging analysis of amygdala-insula functional connectivity. Together, these data suggest that Oprl1 is associated with amygdala function, fear processing, and PTSD symptoms. Further, our data suggest that activation of the Oprl1/NOP receptor may interfere with fear memory consolidation, with implications for prevention of PTSD after a traumatic event.

Topics: Adult; Amygdala; Animals; Anxiety; Conditioning, Psychological; Cues; Disease Models, Animal; Fear; Female; Gene Expression Regulation; Humans; Immobilization; Male; Memory Disorders; Memory, Long-Term; Mice; Mice, Inbred C57BL; Nerve Net; Nociceptin Receptor; Piperidines; Receptors, Opioid; Stress Disorders, Post-Traumatic

Topics: Adolescent; Bullying; Child; Child Abuse, Sexual; Female; Humans; Neuroprotective Agents; Piperidines; Stress Disorders, Post-Traumatic; Treatment Outcome; Young Adult

Topics: Adult Survivors of Child Abuse; Child Abuse, Sexual; Female; Humans; Mental Recall; Piperidines; Stress Disorders, Post-Traumatic

Topics: Adult Survivors of Child Abuse; Child Abuse, Sexual; Female; Humans; Mental Recall; Piperidines; Stress Disorders, Post-Traumatic

Cannabinoids have recently emerged as a possible treatment of stress- and anxiety-related disorders such as post-traumatic stress disorder (PTSD). Here, we examined whether cannabinoid receptor activation could prevent the effects of traumatic stress on the development of behavioral and neuroendocrine measures in a rat model of PTSD, the single-prolonged stress (SPS) model. Rats were injected with the CB1/CB2 receptor agonist WIN55,212-2 (WIN) systemically or into the basolateral amygdala (BLA) at different time points following SPS exposure and were tested 1 week later for inhibitory avoidance (IA) conditioning and extinction, acoustic startle response (ASR), hypothalamic-pituitary-adrenal (HPA) axis function, and anxiety levels. Exposure to SPS enhanced conditioned avoidance and impaired extinction while enhancing ASR, negative feedback on the HPA axis, and anxiety. WIN (0.5 mg/kg) administered intraperitoneally 2 or 24 h (but not 48 h) after SPS prevented the trauma-induced alterations in IA conditioning and extinction, ASR potentiation, and HPA axis inhibition. WIN microinjected into the BLA (5 μg/side) prevented SPS-induced alterations in IA and ASR. These effects were blocked by intra-BLA co-administration of the CB1 receptor antagonist AM251 (0.3 ng/side), suggesting the involvement of CB1 receptors. These findings suggest that (i) there may be an optimal time window for intervention treatment with cannabinoids after exposure to a highly stressful event, (ii) some of the preventive effects induced by WIN are mediated by an activation of CB1 receptors in the BLA, and (iii) cannabinoids could serve as a pharmacological treatment of stress- and trauma-related disorders.

Topics: Amygdala; Animals; Anxiety; Avoidance Learning; Benzoxazines; Cannabinoid Receptor Agonists; Cannabinoid Receptor Antagonists; Cannabinoids; Dexamethasone; Disease Models, Animal; Extinction, Psychological; Humans; Hypothalamo-Hypophyseal System; Injections, Intraperitoneal; Male; Microinjections; Morpholines; Naphthalenes; Piperidines; Pituitary-Adrenal Function Tests; Pituitary-Adrenal System; Pyrazoles; Rats; Rats, Sprague-Dawley; Reflex, Startle; Sensory Gating; Stress Disorders, Post-Traumatic; Stress, Physiological

Topics: Adrenergic alpha-Antagonists; Adult; Adult Survivors of Child Abuse; Child; Child Abuse, Sexual; Female; Humans; Life Change Events; Mental Recall; Middle Aged; Piperidines; Receptors, N-Methyl-D-Aspartate; Stress Disorders, Post-Traumatic; Treatment Outcome

This case report describes a new adverse drug event due to use of donepezil in a patient with probable Alzheimer's Disease.. While receiving a 10-mg dose of donepezil nightly, an 87-year old veteran of World War II experienced irrepressible memories of a kamikaze strike. This symptom did not occur at a 5-mg dose of donepezil and resolved with downward titration of this agent.. This sequence of dosage and symptoms suggests acetylcholinesterase inhibition was the trigger for release of these memories, which are otherwise mostly chronically repressed in this individual.

Topics: Aged, 80 and over; Alzheimer Disease; Cholinesterase Inhibitors; Donepezil; Dose-Response Relationship, Drug; Humans; Indans; Male; Memory, Episodic; Piperidines; Stress Disorders, Post-Traumatic

N-methyl-D-asparate (NMDA)-mediated glutamatergic neurotransmission is strongly involved in the development of trauma-induced behavioral dysfunctions, and indirect evidence suggests that NR2B subunit-expressing NMDA receptors are primarily involved in this process. Earlier studies showed that NR2B blockers inhibit the acquisition of conditioned fear, a frequently used model of post-traumatic stress disorder, but their effects on the expression of conditioned fear was poorly studied. We investigated here the effects of the selective serotonin reuptake blocker, fluoxetine, the NMDA blocker, MK-801, and the NR2B subunit blocker, Ro25-6981 on the expression of conditioned fear. Rats received 10 foot shocks administered over 5 min and were tested 24 h later in the shocking context. Treatments were administered 1 h before testing. Shocks dramatically increased freezing and reduced exploration. MK-801 and Ro25-6981 significantly ameliorated both changes. The effects of fluoxetine were less pronounced. In the open field, MK-801 increased locomotion, ataxia, and stereotypy (effects typical of NMDA blockade). Neither fluoxetine nor Ro25-6981 affected locomotion in the open field. Thus, the NR2B-specific NMDA blockade preserved the beneficial effects of general NMDA antagonists on the expression of conditioned fear but did not produce the locomotor side-effects typical of the latter. These findings warrant further studies on the effects of NR2B antagonists in models of post-traumatic stress disorder.

Topics: Animals; Ataxia; Disease Models, Animal; Dizocilpine Maleate; Electroshock; Excitatory Amino Acid Antagonists; Exploratory Behavior; Fear; Fluoxetine; Freezing Reaction, Cataleptic; Locomotion; Male; Phenols; Piperidines; Rats; Rats, Wistar; Receptors, N-Methyl-D-Aspartate; Selective Serotonin Reuptake Inhibitors; Stereotypic Movement Disorder; Stress Disorders, Post-Traumatic

Recent reports have demonstrated that disruption of CB(1) receptor signaling impairs extinction of learned responses in conditioned fear and Morris water maze paradigms. Here, we test the hypothesis that elevating brain levels of the endogenous cannabinoid anandamide through either genetic deletion or pharmacological inhibition of its primary catabolic enzyme fatty-acid amide hydrolase (FAAH) will potentiate extinction in a fixed platform water maze task. FAAH (-/-) mice and mice treated with the FAAH inhibitor OL-135, did not display any memory impairment or motor disruption, but did exhibit a significant increase in the rate of extinction. Unexpectedly, FAAH-compromised mice also exhibited a significant increase in acquisition rate. The CB(1) receptor antagonist SR141716 (rimonabant) when given alone had no effects on acquisition, but disrupted extinction. Additionally, SR141716 blocked the effects of OL-135 on both acquisition and extinction. Collectively, these results indicate that endogenous anandamide plays a facilitatory role in extinction through a CB(1) receptor mechanism of action. In contrast, the primary psychoactive constituent of marijuana, Delta(9)-tetrahydrocannabinol, failed to affect extinction rates, suggesting that FAAH is a more effective target than a direct acting CB(1) receptor agonist in facilitating extinction. More generally, these findings suggest that FAAH inhibition represents a promising pharmacological approach to treat psychopathologies hallmarked by an inability to extinguish maladaptive behaviors, such as post-traumatic stress syndrome and obsessive-compulsive disorder.

Topics: Amidohydrolases; Animals; Arachidonic Acids; Brain; Brain Chemistry; Cannabinoid Receptor Modulators; Dronabinol; Endocannabinoids; Enzyme Inhibitors; Extinction, Psychological; Female; Lipid Metabolism; Male; Maze Learning; Memory; Mice; Mice, Inbred C57BL; Mice, Knockout; Obsessive-Compulsive Disorder; Piperidines; Polyunsaturated Alkamides; Pyrazoles; Pyridines; Receptor, Cannabinoid, CB1; Rimonabant; Stress Disorders, Post-Traumatic

Topics: Cholinesterase Inhibitors; Cognition Disorders; Donepezil; Galantamine; Humans; Indans; Magnetic Resonance Imaging; Male; Middle Aged; Piperidines; Stress Disorders, Post-Traumatic; Stroke; Veterans