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1.
Australas Emerg Care ; 22(4): 216-220, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31530499

RESUMO

Anxiety and panic symptoms are widespread in the general population. The physical manifestations of anxiety and panic commonly account for people presenting to Emergency Departments (EDs). It is therefore important for ED clinicians to be informed of the numerous causes of anxiety and panic and equipped to respond effectively. This paper describes the underlying pathophysiology of the physical symptoms of anxiety and panic and differential diagnoses to consider. Organic conditions that are associated with symptoms of anxiety and panic are highlighted. Brief interventions are tabled for ED clinicians to use when explaining symptoms, and to promote individual self-management.


Assuntos
Ansiedade/etiologia , Serviço Hospitalar de Emergência , Pânico/fisiologia , Ansiedade/diagnóstico , Ansiedade/terapia , Exercícios Respiratórios/métodos , Diagnóstico Diferencial , Reação de Fuga/fisiologia , Humanos , Hiperventilação/etiologia , Estilo de Vida , Anamnese/métodos , Educação de Pacientes como Assunto , Exame Físico , Terapia de Relaxamento/métodos , Autocuidado/métodos , Estresse Psicológico/etiologia , Estresse Psicológico/terapia
2.
Neuropsychobiology ; 78(4): 209-217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31437853

RESUMO

BACKGROUND: The 35% CO2 challenge is a well-established method triggering panic attacks under laboratory-controlled conditions. There is an ongoing debate whether single or the joined effects of the instructional set and anxiety sensitivity (AS) can alter the outcome of the challenge. OBJECTIVES: The present study investigated the effects of instruction manipulation and AS on panic-like response to the 35% CO2 challenge. METHODS: Eighty healthy subjects, with high or low levels of AS, were randomized into 4 groups based on standard/manipulated instructional sets as well as 35% CO2 mixture/room air inhalation. Subjects filled in the Visual Analogue Scale of Anxiety (VAAS), the Visual Analogue Scale of Fear (VAS-F), the VAS of Discomfort (VAS-D), and the Panic Symptom List (PSL). Blood pressure and heart rate were measured at pre- and posttest. RESULTS: Hierarchical multiple regression analyses showed greater psychological responses at VAAS, VAS-F, VAS-D, and PSL and higher systolic blood pressure under 35% CO2 challenge if compared to room air inhalation while instructional set and AS did not influence the response. CONCLUSIONS: The present study confirms that neither instructional test nor AS alter the outcome of the 35% CO2 challenge.


Assuntos
Antecipação Psicológica/fisiologia , Ansiedade/psicologia , Transtorno de Pânico/psicologia , Pânico/fisiologia , Administração por Inalação , Adolescente , Adulto , Idoso , Dióxido de Carbono/administração & dosagem , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Pânico/efeitos dos fármacos , Adulto Jovem
3.
Behav Brain Res ; 364: 99-105, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30768992

RESUMO

Although the etiology of panic disorder (PD) remains elusive, accumulating evidence suggests a key role for the dorsal periaqueductal gray matter (dPAG). There is also evidence that this midbrain area is critically involved in mediation of the panicolytic effect of antidepressants, which with high potency benzodiazepines (e.g. alprazolam and clonazepam) are first line treatment for PD. Whether the dPAG is also implicated in the antipanic effect of the latter drugs is, however, still unknown. We here investigated the consequences of blocking GABAA or benzodiazepine receptors within the dPAG, with bicuculline (5 pmol) and flumazenil (80 nmol), respectively, on the panicolytic and anxiolytic effects of alprazolam (4 mg/kg). Microinjection of these antagonists fully blocked the anti-escape effect, considered as a panicolytic-like action, caused by a single systemic injection of alprazolam in male Wistar rats submitted to the elevated T-maze. These antagonists, however, did not affect the anxiolytic effect of the benzodiazepine on inhibitory avoidance acquisition and punished responding, measured in the elevated T-maze and Vogel conflict tests, respectively. Altogether, our findings show the involvement of GABAA/benzodiazepine receptors of the dPAG in the panicolytic, but not the anxiolytic effect caused by alprazolam. They also implicate the dPAG as the fulcrum of the effects of different classes of clinically effective antipanic drugs.


Assuntos
Alprazolam/farmacologia , Pânico/efeitos dos fármacos , Substância Cinzenta Periaquedutal/efeitos dos fármacos , Animais , Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Benzodiazepinas/farmacologia , Bicuculina/farmacologia , Reação de Fuga/efeitos dos fármacos , Flumazenil/farmacologia , Antagonistas de Receptores de GABA-A/farmacologia , Masculino , Pânico/fisiologia , Transtorno de Pânico/tratamento farmacológico , Substância Cinzenta Periaquedutal/metabolismo , Ratos , Ratos Wistar , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/farmacologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-30742862

RESUMO

Exposure of rats to an environment with low O2 levels evokes a panic-like escape behavior and recruits the dorsal periaqueductal gray (dPAG), which is considered to be a key region in the pathophysiology of panic disorder. The neurochemical basis of this response is, however, currently unknown. We here investigated the role played by nitric oxide (NO) within the dPAG in mediation of the escape reaction induced by hypoxia exposure. The results showed that exposure of male Wistar rats to 7% O2 increased nitrite levels, a NO metabolite, in the dPAG but not in the amygdala or hypothalamus. Nitrite levels in the dPAG were correlated with the number of escape attempts during the hypoxia challenge. Injections of the NO synthesis inhibitor NPA, the NO-scavenger c- PTIO, or the NMDA receptor antagonist AP-7 into the dorsolateral column of the periaqueductal gray (dlPAG) inhibited escape expression during hypoxia, without affecting the rats' locomotion. Intra-dlPAG administration of c-PTIO had no effect on the escape response evoked by the elevated-T maze, a defensive behavior that has also been associated with panic attacks. Altogether, our results suggest that NO plays a critical role in mediation of the panic-like defensive response evoked by exposure to low O2 concentrations.


Assuntos
Reação de Fuga/fisiologia , Hipóxia/fisiopatologia , Óxido Nítrico/fisiologia , Pânico/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , 2-Amino-5-fosfonovalerato/administração & dosagem , 2-Amino-5-fosfonovalerato/análogos & derivados , 2-Amino-5-fosfonovalerato/farmacologia , Tonsila do Cerebelo/metabolismo , Animais , Arginina/administração & dosagem , Arginina/análogos & derivados , Arginina/farmacologia , Reação de Fuga/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microinjeções , Atividade Motora/efeitos dos fármacos , Nitritos/metabolismo , Substância Cinzenta Periaquedutal/metabolismo , Ratos
5.
Neuropharmacology ; 148: 311-319, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30685402

RESUMO

The role of 5-HT2C receptors (5-HT2CRs) in the regulation of anxiety has been widely acknowledged. However, conflicting results have been reported on whether stimulation of these receptors increases or decreases anxiety. We here investigated the role of 5-HT2CRs of the dorsal hippocampus (DH) in the mediation of anxiety- or panic-associated defensive behaviors and in the anxiolytic effect of the tricyclic antidepressant imipramine. In the Vogel conflict test, administration of the mixed 5-HT2CR agonist mCPP into the DH of male Wistar rats was anxiogenic, whereas infusions of the more selective agonists MK-212 and RO-600175 were anxiolytic. The 5-HT2CR antagonist SB-242084, on the other hand, was anxiogenic. A sub-effective dose of this antagonist blocked the anxiolytic effect of RO-600175, but not the increase in anxiety observed with mCPP, indicating that the latter effect was not due to 5-HT2CR activation. In full agreement with these findings, MK-212 and RO-600175 in the DH also inhibited inhibitory avoidance acquisition in the elevated T-maze, whereas SB-242084 caused the opposite effect. None of these drugs interfered with escape expression in this test, which has been associated with panic. Chronic administration of imipramine (15 mg/kg, ip, 21 days) caused an anxiolytic effect in the elevated T-maze and light-dark transition tests, which was not blocked by previous infusion of SB-242084 into the DH. Therefore, facilitation of 5-HT2CR-mediated neurotransmission in the DH decreases the expression of anxiety-, but not panic-related defensive behaviors. This mechanism, however, is not involved in the anxiolytic effect caused by imipramine.


Assuntos
Ansiedade/fisiopatologia , Hipocampo/fisiologia , Pânico/fisiologia , Receptor 5-HT2C de Serotonina/fisiologia , Aminopiridinas/farmacologia , Animais , Ansiolíticos/farmacologia , Ansiedade/induzido quimicamente , Aprendizagem da Esquiva/efeitos dos fármacos , Etilaminas/antagonistas & inibidores , Etilaminas/farmacologia , Hipocampo/efeitos dos fármacos , Imipramina/farmacologia , Indóis/antagonistas & inibidores , Indóis/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microinjeções , Pânico/efeitos dos fármacos , Piperazinas/antagonistas & inibidores , Piperazinas/farmacologia , Punição , Pirazinas/farmacologia , Ratos , Agonistas do Receptor 5-HT2 de Serotonina
6.
Psychopharmacology (Berl) ; 236(6): 1863-1874, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30694375

RESUMO

RATIONALE: The endocannabinoid system plays an important role in the organization of panic-like defensive behavior. Threatening situations stimulate brain areas, such as the dorsomedial hypothalamus (DMH). However, there is a lack of studies addressing the role of the DMH endocannabinoid system in panic-like responses. OBJECTIVES: We aimed to verify which mechanisms underlie anandamide-mediated responses in the DMH. METHODS: To test the hypothesis that the anandamide produces panicolytic-like effects, we treated mice with intra-DMH microinjections of vehicle or increasing doses of anandamide (0.5, 5, or 50 pmol) and then performed confrontation with the South American snake Epicrates cenchria assisi. RESULTS: Intra-DMH anandamide treatment yielded a U-shaped dose-response curve with no effect of the lowest (0.5 pmol) or the highest (50 pmol) dose and significant inhibition of panic-like responses at the intermediate (5 pmol) dose. In addition, this panicolytic-like effect was prevented by pretreatment of the DMH with the CB1 receptor antagonist AM251 (100 pmol). However, pretreatment of the DMH with the TRPV1 receptor antagonist 6-iodo-nordihydrocapsaicin (3 nmol) restored the panicolytic-like effect of the highest dose of anandamide. Immunohistochemistry revealed that CB1 receptors were present primarily on axonal fibers, while TRPV1 receptors were found almost exclusively surrounding the perikarya in DMH. CONCLUSIONS: The present results suggest that anandamide exerts a panicolytic-like effect in the DMH by activation of CB1 receptors and that TRPV1 receptors are related to the lack of effect of the highest dose of anandamide.


Assuntos
Ácidos Araquidônicos/administração & dosagem , Agonistas de Receptores de Canabinoides/administração & dosagem , Núcleo Hipotalâmico Dorsomedial/metabolismo , Endocanabinoides/administração & dosagem , Pânico/fisiologia , Alcamidas Poli-Insaturadas/administração & dosagem , Receptor CB1 de Canabinoide/biossíntese , Canais de Cátion TRPV/biossíntese , Animais , Boidae , Brasil , Núcleo Hipotalâmico Dorsomedial/efeitos dos fármacos , Relação Dose-Resposta a Droga , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pânico/efeitos dos fármacos , Piperidinas/administração & dosagem , Pirazóis/administração & dosagem , Ratos , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Canais de Cátion TRPV/antagonistas & inibidores
7.
Artigo em Inglês | MEDLINE | ID: mdl-29805056

RESUMO

BACKGROUND: Internalizing disorders such as anxiety may be characterized by an imbalance between bottom-up (stimulus-driven) and top-down (goal-directed) attention. The late positive potential (LPP) can be used to assess these processes when task-irrelevant negative and neutral pictures are presented within a working memory paradigm. Prior work using this paradigm has found that working memory load reduces the picture-elicited LPP across participants; however, anxious individuals showed a reduced effect of working memory load on the LPP, suggesting increased distractibility. METHODS: The current study assessed transdiagnostic associations between specific symptom dimensions of anxiety, the LPP, and behavior in a clinically representative, heterogeneous group of 76 treatment-seeking patients with internalizing disorders, who performed a working memory task interspersed with negative and neutral pictures. RESULTS: As expected, negative pictures enhanced the LPP, and working memory load reduced the LPP. Participants with higher social anxiety showed increased LPPs to negative stimuli during early and late portions of picture presentation. Panic symptoms were associated with reduced LPPs to negative pictures compared with neutral pictures as well as a reduced effect of working memory load on the LPP during the late time window. Reduced positive affect was associated with greater behavioral interference from negative pictures. CONCLUSIONS: Hypervigilance for negative stimuli was uniquely explained by social anxiety symptoms, whereas panic symptoms were associated with the opposing effect-blunted processing/avoidance of these stimuli. Panic symptoms were uniquely associated with reduced top-down control. Results reveal distinct associations between neural reactivity and anxiety symptom dimensions that transcend traditional diagnostic boundaries.


Assuntos
Afeto/fisiologia , Transtornos de Ansiedade/fisiopatologia , Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Transtorno Depressivo/fisiopatologia , Memória de Curto Prazo/fisiologia , Pânico/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Ansiedade/complicações , Transtornos de Ansiedade/complicações , Transtorno Depressivo/complicações , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
8.
Behav Pharmacol ; 30(4): 376-382, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30480550

RESUMO

Panic attacks (PAs) are episodes of intense fear or discomfort that are accompanied by a variety of both psychological and somatic symptoms. Panic induction in preclinical models (e.g. rats) has largely been assayed through flight and avoidance behavioral tests and cardiorespiratory activity. Yet, the literature pertaining to PAs shows that thermal sensations (hot flushes/heat sensations and chills) are also a common symptom during PAs in humans. Considering that temperature alterations are objectively measurable in rodents, we hypothesized that select panicogenic drugs and stimuli induce consistent changes in thermoregulation related to hot flushes and chills. Specifically, we challenged male rats with intraperitoneal injections of the GABAergic inverse agonist FG-7142; the α2 adrenoceptor antagonist yohimbine; the serotonin agonist D-fenfluramine, and 20% CO2 (an interoceptive homeostatic challenge). We assayed core body temperature and tail skin temperature using implanted radiotelemetry probes and tail thermistors/thermal imaging camera, respectively, and found that all challenges elicited rapid, high-amplitude (~7-9°C) increase in tail skin temperature and delayed decreases (~1-3°C) in core body temperature. We propose that thermal sensations such as these may be an additional indicator of a panic response in rodents and humans, as these panicogenic compounds or stimuli are known to precipitate PAs in persons with panic disorder.


Assuntos
Regulação da Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Transtorno de Pânico/fisiopatologia , Animais , Temperatura Corporal/fisiologia , Carbolinas/farmacologia , Fenfluramina/farmacologia , Masculino , Modelos Animais , Pânico/fisiologia , Ratos , Ratos Sprague-Dawley , Temperatura Cutânea/efeitos dos fármacos , Temperatura Cutânea/fisiologia , Ioimbina/farmacologia
9.
Undersea Hyperb Med ; 45: 505-509, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30428239

RESUMO

Panic arising from physical or psychological stress is a common issue in reported incidents and accidents in scuba diving. Due to its effect on perception, thinking and diver behavior, the panic reaction is often a significant factor in the generation or escalation of problems, potentially leading to injuries and fatalities. The instinctive behaviors associated with panic are incompatible with the constraints of scuba diving (e.g., flight response to threat, leading to rapid ascent). Although the dangers are well known, the psychological mechanisms of panic and the implications for prevention/risk reduction are not sufficiently highlighted to recreational divers. In applied psychology, there are grounded theoretical models which describe the onset and maintenance of anxiety and panic, and an evidence base for approaches to anxiety management. For example, these models are used within structured psychological approaches for people experiencing anxiety disorders; and panic attacks are resolvable. Based on these models and underlying theory, this article proposes a new, accessible model for panic in divers. The potential uses of the model are to: (1) provide a simple framework for divers to understand the onset of panic; (2) promote the need for adequate training; (3) describe the importance of staying within training standards, qualifications and personal limitations; (4) support diver and dive educator understanding of individual factors in panic reactions (e.g. psychiatric conditions) placing greater emphasis on psychological fitness to dive; and (5) draw attention to approaches to improved regulation of emotion and promote individual responsibility.


Assuntos
Nível de Alerta/fisiologia , Mergulho/psicologia , Modelos Psicológicos , Pânico/fisiologia , Prevenção de Acidentes , Acidentes/psicologia , Ansiedade/psicologia , Mergulho/educação , Mergulho/fisiologia , Falha de Equipamento , Humanos , Autocontrole , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia
10.
Epilepsy Behav ; 85: 115-119, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29940374

RESUMO

The purpose of the current paper was to review the empirical literature on the cooccurrence of panic and epilepsy, in order to determine whether there is an increased risk of panic attacks and panic disorder among adults with epilepsy and an increased risk of epilepsy among adults with panic disorder. Given the overlap between panic and ictal fear, a preliminary aim of the current review was to critically evaluate the methodology used to differentiate between diagnoses of panic disorder and epilepsy in existing research. A literature search was conducted in relevant electronic databases, and articles that directly focused on panic and epilepsy among adults were selected for the current review (n = 17). Overall, results suggest that rates of epilepsy are elevated among individuals with panic disorder and that panic attacks are elevated among individuals with epilepsy, but rates of panic disorder among people with epilepsy are inconsistent. However, most studies did not use sufficiently rigorous methods to differentiate between panic disorder and epilepsy. Therefore, a critical next step in this area of research is to develop a standard procedure for differentiating ictal fear from panic attacks and panic disorder.


Assuntos
Epilepsia/diagnóstico , Epilepsia/psicologia , Transtorno de Pânico/diagnóstico , Transtorno de Pânico/psicologia , Adulto , Epilepsia/epidemiologia , Medo/fisiologia , Medo/psicologia , Feminino , Humanos , Masculino , Pânico/fisiologia , Transtorno de Pânico/epidemiologia
11.
Behav Brain Res ; 353: 32-39, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29953907

RESUMO

Predators induce defensive responses and fear behaviours in prey. The rat exposure test (RET) is frequently used as an animal model of panic. Nitric oxide (NO) which has been reported to be activated by the NMDA receptor, in turn mediates calcium/calmodulin-dependent protein kinase II (CaMKII) signalling pathways in defensive responses. ACCN2, the orthologous human gene of acid-sensing ion channel 1a (ASIC1a), is also associated with panic disorder; however, few studies have focused on the role of ASIC1a in the modulation of panic and calcium/CaMKII signalling by NO. In the present study, NG-nitro-L-arginine-methyl-ester (L-NAME; non-selective NOS inhibitor), S-nitroso-N-acetyl-D,L-penicillamine (SNAP; NO donor), and psalmotoxin (PcTx-1; selective ASIC1a blocker) were administered to the dorsal periaqueductal grey (dPAG) before the predator stimulus, and the roles of NO in the expression of ASIC1a, phosphorylation of CaMKIIα (p-CaMKIIα) and expression of calmodulin (CaM) were investigated. The effects of ASIC1a, p-CaMKIIα and CaM regulation were also examined. Our results showed that intra-dPAG infusion of L-NAME weakened panic-like behaviour and decreased ASIC1a, p-CaMKIIα and CaM expression levels, whereas intra-dPAG infusion of SNAP enhanced panic-like behaviour and increased ASIC1a, p-CaMKIIα and CaM levels. Intra-dPAG infusion of PcTx-1 also weakened panic-like behaviour and decreased p-CaMKIIα expression level. Taken together, these results indicate that NO and ASIC1a are involved in the modulation of RET-induced panic-like behaviour in the dPAG. NO regulates the calcium/CaMKII signalling pathways, and ASIC1a participates in this regulation.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Óxido Nítrico/metabolismo , Pânico/fisiologia , Substância Cinzenta Periaquedutal/metabolismo , Animais , Comportamento Animal/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Calmodulina/metabolismo , Fármacos do Sistema Nervoso Central/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Substância Cinzenta Periaquedutal/efeitos dos fármacos
12.
Artigo em Inglês | MEDLINE | ID: mdl-29573981

RESUMO

BACKGROUND: Previous research has shown that hypoventilation therapy reduces panic symptoms in part by increasing basal partial pressure of carbon dioxide (PCO2) levels. We tested an additional pathway by which hypoventilation therapy could exert its therapeutic effects: through repeated interoceptive exposure to sensations of dyspnea. METHODS: A total of 35 patients with panic disorder were trained to perform exercises to raise their end-tidal PCO2 levels using a portable capnometry device. Anxiety, dyspnea, end-tidal PCO2, and respiratory rate were assessed during each exercise across 4 weeks of training. Mixed-model analysis examined whether within-exercise levels of dyspnea were predictive of reduction of panicogenic cognitions. RESULTS: As expected, within-exercise anxiety and respiratory rate decreased over time. Unexpectedly, PCO2 dropped significantly from the beginning to the end of exercise, with these drops becoming progressively smaller across weeks. Dyspnea increased and remained consistently above basal levels across weeks. As hypothesized, greater dyspnea was related to significantly lower panicogenic cognitions over time even after controlling for anxiety and PCO2. Additional exploratory analyses showed that within-exercise increases in dyspnea were related to within-exercise increases in anxiety but were not related to within-exercise increases in PCO2. CONCLUSIONS: In support of the interoceptive exposure model, we found that greater dyspnea during hypoventilation exercises resulted in lower panicogenic cognitions even after the effect of PCO2 was taken into account. The findings offer an additional important target in panic treatment.


Assuntos
Ansiedade/terapia , Dispneia/etiologia , Hipoventilação/metabolismo , Transtorno de Pânico/terapia , Pânico/fisiologia , Adolescente , Adulto , Dispneia/terapia , Terapia por Exercício/métodos , Feminino , Humanos , Hiperventilação/terapia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Behav Brain Res ; 344: 132-144, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29466713

RESUMO

The present study examined whether early life maternal separation (MS), a model of childhood separation anxiety, predisposes to panic at adulthood. For this purpose, male pups were submitted to 3-h daily maternal separations along postnatal (PN) days of either the 'stress hyporesponsive period' (SHRP) from PN4 to PN14 (MS11) or throughout lactation from PN2 to PN21 (MS20). Pups were further reunited to conscious (CM) or anesthetized (AM) mothers to assess the effect of mother-pup interaction upon reunion. Controls were subjected to brief handling (15 s) once a day throughout lactation (BH20). As adults (PN60), rats were tested for the thresholds to evoke panic-like behaviors upon electrical stimulation of dorsal periaqueductal gray matter and exposed to an elevated plus-maze, an open-field, a forced swim and a sucrose preference test. A factor analysis was also performed to gain insight into the meaning of behavioral tests. MS11-CM rather than MS20-CM rats showed enhanced panic responses and reductions in both swimming and sucrose preference. Panic facilitations were less intense in mother-neglected rats. Although MS did not affect anxiety, MS11-AM showed robust reductions of defecation in an open-field. Factor analysis singled out anxiety, hedonia, exploration, coping and gut activity. Although sucrose preference and coping loaded on separate factors, appetite (adult weight) correlated with active coping in both forced swim and open-field (central area exploration). Concluding, whereas 3h-daily maternal separations during SHRP increased rat's susceptibility to experimental panic attacks, separations throughout lactation had no effects on panic and enhanced active coping.


Assuntos
Período Crítico Psicológico , Privação Materna , Pânico/fisiologia , Substância Cinzenta Periaquedutal/fisiopatologia , Estresse Psicológico/fisiopatologia , Adaptação Psicológica , Animais , Animais Recém-Nascidos , Ansiedade/fisiopatologia , Apetite , Suscetibilidade a Doenças , Estimulação Elétrica , Comportamento Exploratório , Comportamento Alimentar , Lactação , Masculino , Atividade Motora , Ratos Wistar , Resiliência Psicológica
14.
Artigo em Inglês | MEDLINE | ID: mdl-29397080

RESUMO

BACKGROUND: Abnormal patterns of attention to threat and reward have been proposed as potential mechanisms of dysfunction in anxiety and mood disorders. However, research on this topic has been inconsistent, perhaps because of both clinical heterogeneity in the samples assessed and measurement of attentional biases that is temporally imprecise. METHODS: The present study measured transdiagnostic symptoms of anxiety and depression in 205 young adults and recorded affect-modulated event-related potentials in response to task-irrelevant pictures in a speeded response task. RESULTS: Low positive affect was uniquely associated with reduced modulation of later event-related potentials (i.e., the P300 and the late positive potential) by rewarding images, suggesting deficits in sustained attention to reward. Low positive affect was also associated with a blunted threat-elicited late positive potential. Symptoms of panic were associated with an increased N1 to rewarding images, as well as an increased late positive potential to all picture types. CONCLUSIONS: These data suggest that dysfunction in neural markers of sustained attention to threat and reward relate in specific ways to transdiagnostic symptom dimensions of anxiety and depression. Moreover, event-related potentials are likely to be useful in investigations of the time course of attentional abnormalities associated with these symptom dimensions.


Assuntos
Afeto/fisiologia , Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Depressão/fisiopatologia , Pânico/fisiologia , Recompensa , Adolescente , Adulto , Atenção/fisiologia , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Percepção Visual , Adulto Jovem
15.
J Psychiatr Res ; 96: 260-264, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29128558

RESUMO

BACKGROUND: In patients with post-traumatic stress disorder (PTSD) two open pilot studies about the effects of 35% carbon dioxide (CO2) exist. One shows an augmented panicogenic and anxiogenic response (Muhtz et al., 2011), the other does not (Talesnik et al. 2007). We further characterized the CO2 reactivity in PTSD using for the first time placebo-controlled and double-blind conditions. METHODS: In 20 patients with PTSD we assessed panic, anxiety, dissociative and PTSD symptoms after a single vital capacity inhalation of 35% CO2 compared to a placebo gas condition in a within-participant cross-over, placebo-controlled, double-blind and randomized design. RESULTS: Inhalation of 35% CO2 versus placebo provoked significantly increased panic, anxiety, dissociative and PTSD symptoms. The reaction to placebo gas was minimal. Order of inhalation, patients' sex or age did not influence the results. The panic and anxiety response under CO2 was considerably higher in the PTSD patients than in healthy controls from our previous open study. CONCLUSIONS: The results corroborate that our preceding findings of an increased CO2 reactivity in patients with PTSD are not false positive due to the open design or the lack of placebo control. Replication in a larger number of PTSD patients and matched control subjects is needed. The potential role of childhood traumatisation, psychiatric comorbidity, psychotropic medication and trait dissociation in prior contradictory reports should be clarified.


Assuntos
Dióxido de Carbono/administração & dosagem , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/psicologia , Administração por Inalação , Adulto , Ansiedade/metabolismo , Doença Crônica , Estudos Cross-Over , Transtornos Dissociativos/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pânico/fisiologia , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
16.
Neuroscience ; 369: 336-349, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29183829

RESUMO

Using an innovative approach to study the neural bases of psychiatric disorders, this study investigated the behavioral, morphological and pharmacological bases of panic attack-induced responses in a prey-versus-coral snake paradigm. Mesocricetus auratus was chronically treated with intraperitoneal administration of the selective serotonin uptake inhibitor paroxetine or the gamma aminobutyric acid (GABA)/benzodiazepine receptor agonist alprazolam at three different doses and were then confronted with a venomous coral snake (Micrurus frontalis, Reptilia, Elapidae). The threatened rodents exhibited defensive attention, flat back approaches, defensive immobility, and escape defensive responses in the presence of the venomous snake, followed by increases in Fos protein in limbic structure neurons. Chronic administration of both paroxetine and alprazolam decreased these responses with morphological correlates between the panicolytic effect of both drugs administered at the highest dose and decreases in Fos protein-immunolabeled perikarya found in the amygdaloid complex, hypothalamus and periaqueductal gray matter columns, which are structures that make up the encephalic aversion system. These findings provide face, construct and predictive validities of this new experimental model of anxiety- and panic attack-like behavioral responses displayed by threatened prey confronted with venomous coral snakes.


Assuntos
Ansiedade , Modelos Animais , Transtorno de Pânico , Pânico , Comportamento Predatório , Alprazolam/farmacologia , Animais , Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Ansiedade/patologia , Relação Dose-Resposta a Droga , Elapidae , Reação de Fuga/fisiologia , Sistema Límbico/efeitos dos fármacos , Sistema Límbico/metabolismo , Sistema Límbico/patologia , Masculino , Mesocricetus , Pânico/efeitos dos fármacos , Pânico/fisiologia , Transtorno de Pânico/dietoterapia , Transtorno de Pânico/metabolismo , Transtorno de Pânico/patologia , Paroxetina/farmacologia , Proteínas Proto-Oncogênicas c-fos/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-29111406

RESUMO

Exposure to elevated concentrations of CO2 or hypoxia has been widely used in psychiatric research as a panic provoking stimulus. However, the use of these respiratory challenges to model panic-like responses in experimental animals has been less straightforward. Little data is available, from behavioral and endocrine perspectives, to support the conclusion that a marked aversive situation, such as that experienced during panic attacks, was evoked in these animals. We here compared the behavioral responses of male CB57BL/6 mice during exposure to 20% CO2 or 7% O2 and its consequence on plasma levels of corticosterone. We also evaluated whether clinically-effective panicolytic drugs affect the behavioral responses expressed during CO2 exposure. The results showed that whereas hypoxia caused a marked reduction in locomotion, inhalation of CO2-enriched air evoked an active escape response, characterized by bouts of upward leaps directed to the border of the experimental cage, interpreted as escape attempts. Corticosterone levels were increased 30min after either of the respiratory challenges used, but it was higher in the hypoxia group. Chronic (21days), but not acute, treatment with fluoxetine or imipramine (5, 10 or 15mg/kg) or a single injection of alprazolam (0.025, 0.05 or 0.1mg/kg), but not of the anxiolytic diazepam (0.025, 0.05 or 0.1 and 1mg/kg) reduced the number of escape attempts, indicating a panicolytic-like effect. Altogether, the results suggest that whereas hypoxia increased anxiety, exposure to 20% CO2 evoked a panic-like state. The latter condition/test protocol seems to be a simple and validated model for studying in mice pathophysiological mechanisms and the screening of novel drugs for panic disorder.


Assuntos
Dióxido de Carbono/metabolismo , Reação de Fuga/fisiologia , Hipóxia/fisiopatologia , Pânico/fisiologia , Alprazolam/farmacologia , Análise de Variância , Animais , Dióxido de Carbono/administração & dosagem , Corticosterona/metabolismo , Diazepam/farmacologia , Relação Dose-Resposta a Droga , Reação de Fuga/efeitos dos fármacos , Fluoxetina/farmacologia , Hipóxia/psicologia , Imipramina/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Pânico/efeitos dos fármacos , Psicotrópicos/farmacologia , Distribuição Aleatória
18.
Diving Hyperb Med ; 47(4): 248-252, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29241235

RESUMO

This paper provides a brief overview of the shift from studies describing the personality profiles of divers to studies exploring associations between personality variables and diving performance in terms of behavioural outcomes. The personality associations that were investigated include performance during training, panic proneness, diving injuries, susceptibility to inert gas narcosis, and the behaviour of tourist divers. The paper concludes with a number of suggested directions for further research on personality and diving that may provide tangible benefits in terms of both enhanced safety and improved performance underwater.


Assuntos
Mergulho/psicologia , Determinação da Personalidade , Personalidade , Pesquisa Comportamental , Humanos , Narcose por Gás Inerte/etiologia , Narcose por Gás Inerte/psicologia , Militares/psicologia , Pânico/fisiologia , Testes de Personalidade , Resiliência Psicológica , Assunção de Riscos
19.
Transl Psychiatry ; 7(12): 1266, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29213110

RESUMO

Panic disorder is characterized by sudden, repeated, and unexpected attacks of intense fear and overwhelming anxiety about when another attack may strike. Patients with panic disorder and healthy individuals with a history of panic attacks show a hypersensitivity to unpredictable threats, suggesting a possible link between panic and sustained anxiety. The purpose of this study was to determine the degree to which induced symptoms of panic relate to fear and anxiety, as well as activity in the neural systems that mediate and regulate these affective states. Psychological and physiological symptoms of panic were assessed during an 8-min 7.5% CO2 challenge task. Psychological, physiological, and neural symptoms of fear and anxiety were measured during two sessions (one psychophysiology and one functional magnetic resonance imaging where subjects experienced several blocks of no threat (N), predictable shock (P), and unpredictable shock (U; NPU threat task). We used a principle component analysis to characterize panic susceptibility (PS), and found that PS significantly predicted dorsolateral prefrontal cortex (dlPFC) activity to the unpredictable cue during the NPU threat task. When examining the weighted beta coefficients from this analysis, we observed that self-reported fear/anxiety during the CO2 challenge negatively loaded onto dlPFC activity during the NPU task. Consistent with this observation, dlPFC activity during the unpredictable cue was also negatively correlated with anxiety during the NPU sessions. Together, these results suggest that panic symptoms and anxiety are regulated by the same prefrontal cognitive control system.


Assuntos
Ansiedade/diagnóstico por imagem , Dióxido de Carbono/administração & dosagem , Medo/fisiologia , Pânico/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Adulto , Ansiedade/fisiopatologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/fisiopatologia , Adulto Jovem
20.
Epilepsy Behav ; 77: 33-38, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29107199

RESUMO

Anxiety is one of the most common comorbidities of epilepsy, which has major detrimental effects on the quality of life. Generalized anxiety disorder (GAD) associated with epilepsy has been receiving most attention. However, several other forms of anxiety reportedly present in patients with epilepsy, including panic disorder (PD). In this study, using an animal model of limbic epilepsy, we examined the interplay between epilepsy and panic-like behavior (PLB). Further, considering the high degree of comorbidity between depression on the one hand, and both epilepsy and PD on the other hand, we studied whether and how the presence of PLB in animals with epilepsy would affect their performance in depression-relevant tests. Fifty-day-old male Wistar rats were subjected to repeated alternating electrical stimulations of the basolateral amygdala (BLA) to induce kindling of limbic seizures, and the dorsal periaqueductal gray (DPAG) to induce panic-like episodes. Seizure susceptibility and panic reaction threshold were examined before the first and 24h after the last stimulation. At the end of the stimulations, the rats were examined in depression-relevant tests: saccharin preference test (SPT) for anhedonia and forced swimming test (FST) for despair/hopelessness. With regard to kindling, BLA+DPAG stimulation induced more profound increase of seizure susceptibility than BLA stimulation alone (evident as the reduction of the afterdischarge threshold and the increase of the afterdischarge duration). With regard to PLB, the BLA+DPAG stimulation exacerbated the severity of panic-like episodes, as compared with the DPAG stimulation alone. Basolateral amygdala stimulation alone had no effects on panic-like reactions, and DPAG stimulation alone did not modify kindling epileptogenesis. Combined stimulation of BLA and DPAG induced depressive-like behavioral impairments. This is the first experimental study showing bidirectional, mutually exacerbating effect of epilepsy and PLB, and the precipitation of depressive-like state by the epilepsy-PLB comorbidity.


Assuntos
Comportamento Animal/fisiologia , Depressão/fisiopatologia , Epilepsia/fisiopatologia , Excitação Neurológica/fisiologia , Pânico/fisiologia , Substância Cinzenta Periaquedutal/fisiopatologia , Tonsila do Cerebelo/fisiopatologia , Animais , Ansiedade/fisiopatologia , Ansiedade/psicologia , Depressão/psicologia , Estimulação Elétrica , Epilepsia/psicologia , Masculino , Ratos , Ratos Wistar , Convulsões/fisiopatologia , Convulsões/psicologia
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