Percepção de risco como estratégia de convívio comensal com jovens órfãos pelo HIV/AIDS em São Paulo, SP, Brasil / Percepción de riesgo como estrategia de convivencia comensal con jóvenes huérfanos por VIH/SIDA en São Paulo, SP, Brasil / Commensal meetings strategies regarding youth orphaned by HIV/AIDS in São Paulo, SP, Brazil

No contexto do HIV/AIDS, estratégias comensais são acordadas pelas famílias para reduzir riscos. Com o objetivo de identificar percepções de risco nos convívios comensais desenvolveu-se estudo qualitativo com jovens órfãos pela AIDS. Os dados foram obtidos durante entrevista com questões sobre o cotidiano. Utilizou-se a proposta de Wright Mills do artesanato intelectual, na qual os sujeitos são considerados atores históricos e sociais. As estratégias mediante a percepção de risco ao HIV/AIDS foram consideradas acordos pactuados pela família para assegurar a interação social. Foi possível observar que as estratégias incluem a restrição do toque e do contato corporal; separação de utensílios e inutilização da comida tocada por soropositivos. A percepção de risco pode ser decorrente da inconstância dos achados científicos e de crenças que reforçam o processo de estigma e discriminação.(AU)

En el contexto del VIH/SIDA, las familias acuerdan estrategias comensales para reducir riesgos. Con el objetivo de identificar percepciones de riesgo en las convivencias comensales se desarrolló un estudio cualitativo con jóvenes huérfanos debido al SIDA. Los datos se obtuvieron durante entrevista con preguntas sobre el cotidiano. Se utilizó la propuesta de Wright Mills de la artesanía intelectual, en la cual los sujetos se consideran actores históricos y sociales. Las estrategias mediante la percepción de riesgo del VIH/SIDA se consideraron acuerdos pactados por la familia para asegurar la interacción social. Fue posible observar que las estrategias incluyen la restricción del toque y del contacto corporal, separación de utensilios e inutilización de la comida tocada por personas que son seropositivas. La percepción del riesgo puede ser consecuencia de la inconstancia de los hallazgos científicos y de creencias que refuerzan el proceso de estigmatización y discriminación.(AU)

Within the HIV/AIDS context, commensal strategies are agreed upon by the families aiming to reduce risks. With the objective of identifying risk perceptions in the commensal meetings, we developed a study with youth orphaned by AIDS. Interviews produced data through questions regarding daily life. The Wright Mills' proposal about intellectual craftsmanship was used for analysis. In this approachsubjects are considered historical and social actors. The strategies used from risk perception of HIV/AIDS were assumed as agreements by the families to ensure social interaction. It was observed that strategies include restrictions for touching and body contact; separation of dishes and disposal of food touched by the HIVpositive. The risk perception found may be due to variability of scientific findings and beliefs, thus reinforcing the process of stigma and discrimination.(AU)

Hatha Yoga practice decreases menopause symptoms and improves quality of life: A randomized controlled trial.

OBJECTIVES: Yoga practice includes a group of specific psychophysical techniques. Although previous studies showed beneficial effects of yoga for health and rehabilitation, improving quality of life, there are few studies on the possible therapeutic application of yoga during the climacteric period. The purpose of this study was to investigate the psychophysiological effects of Hatha Yoga regular practice in post-menopausal women. METHODS: Eighty-eight post-menopausal women volunteered for this 12-week trial. They were randomly assigned to one of three groups: control (no intervention), exercise, and yoga. Questionnaires were applied in order to evaluate climacteric syndrome (Menopause Rating Scale), stress (Lipp Stress Symptom Inventory), quality of life (Brief World Health Organization Quality of Life), depression (Beck Depression Inventory) and anxiety (State/Trait Anxiety Inventories). Physiological changes were evaluated through hormone levels (cortisol, FSH, LH, progesterone and estradiol). RESULTS: At 12 weeks, yoga practitioners showed statistically lower scores for menopausal symptoms, stress levels and depression symptoms, as well as significantly higher scores in quality of life when compared to control and exercise groups. Only control group presented a significant increase in cortisol levels. The yoga and exercise groups showed decreased levels of FSH and LH when compared to control group. CONCLUSIONS: These results suggest that yoga promotes positive psychophysiological changes in post-menopausal women and may be applied as a complementary therapy towards this population.

Hippocampal-dependent memory in the plus-maze discriminative avoidance task: The role of spatial cues and CA1 activity.

The plus-maze discriminative avoidance task (PMDAT) has been used to investigate interactions between aversive memory and an anxiety-like response in rodents. Suitable performance in this task depends on the activity of the basolateral amygdala, similar to other aversive-based memory tasks. However, the role of spatial cues and hippocampal-dependent learning in the performance of PMDAT remains unknown. Here, we investigated the role of proximal and distal cues in the retrieval of this task. Animals tested under misplaced proximal cues had diminished performance, and animals tested under both misplaced proximal cues and absent distal cues could not discriminate the aversive arm. We also assessed the role of the dorsal hippocampus (CA1) in this aversive memory task. Temporary bilateral inactivation of dorsal CA1 was conducted with muscimol (0.05 µg, 0.1 µg, and 0.2 µg) prior to the training session. While the acquisition of the task was not altered, muscimol impaired the performance in the test session and reduced the anxiety-like response in the training session. We also performed a spreading analysis of a fluorophore-conjugated muscimol to confirm selective inhibition of CA1. In conclusion, both distal and proximal cues are required to retrieve the task, with the latter being more relevant to spatial orientation. Dorsal CA1 activity is also required for aversive memory formation in this task, and interfered with the anxiety-like response as well. Importantly, both effects were detected by different parameters in the same paradigm, endorsing the previous findings of independent assessment of aversive memory and anxiety-like behavior in the PMDAT. Taken together, these findings suggest that the PMDAT probably requires an integration of multiple systems for memory formation, resembling an episodic-like memory rather than a pure conditioning behavior. Furthermore, the concomitant and independent assessment of emotionality and memory in rodents is relevant to elucidate how these memory systems interact during aversive memory formation. Thus, the PMDAT can be useful for studying hippocampal-dependent memory when it involves emotional content.

Diazepam effects on aversive memory retrieval and extinction: Role of anxiety levels.

Benzodiazepines (BDZs) are anxiolytic drugs that impair memory acquisition. Previous studies using the plus-maze discriminative avoidance task (PMDAT, which assesses memory and anxiety concomitantly) indicated that the effects of BDZs on anxiety and acquisition are related to each other. The possible influence of the anxiolytic action of BDZs on their effects on memory retrieval and extinction are poorly understood. This is relevant considering the relationship between aversive memories and anxiety disorders. We designed a modified protocol of PMDAT that evaluates anxiety during retrieval and extinction of the task. Male Wistar rats were trained in the PMDAT (plus-maze with two open and two enclosed arms) using a standard or a modified protocol. In the standard protocol, the aversive stimuli were presented in one of the enclosed arms during training, and the animal had free access to the whole apparatus. In the modified protocol, the open arms were blocked with glass walls. Twenty-four hours after training, the animals subjected to each of the protocols were treated with saline or 2.0mg/kg of diazepam (DZP) 30min before the test. There was a third session in the maze (retest) 24h after the test. During the test, DZP impaired and improved retrieval in rats that had been trained in the standard and the modified protocol when compared to the respective saline-treated groups. In addition, treatment with DZP prior to the test induced anxiolysis, but only in the animals that were not pre-exposed to the open arms of the apparatus (modified protocol). In these animals, DZP impaired extinction, which was evaluated during retest session. The impairing effect of DZP on extinction seems to be related to its anxiolytic action during the test (extinction learning). Further, we suggest that aversive memory retrieval depends on both the treatment and the arousal elicited by exposure to the apparatus.

Estrogen levels modify scopolamine-induced amnesia in gonadally intact rats.

Previous studies suggested that estrogen plays a role in cognitive function by modulating the cholinergic transmission. However, most of the studies dealing with this subject have been conducted using ovariectomized rats. In the present study we evaluated the effects of physiological and supra-physiological variation of estrogen levels on scopolamine-induced amnesia in gonadally intact female rats. We used the plus-maze discriminative avoidance task (PMDAT) in order to evaluate anxiety levels and motor activity concomitantly to the memory performance. In experiment 1, female Wistar rats in each estrous cycle phase received scopolamine (1 mg/kg) or saline i.p. 20 min before the training session in the PMDAT. In experiment 2, rats in diestrus received estradiol valerate (1 mg/kg) or sesame oil i.m., and scopolamine (1 mg/kg) or saline i.p., 45 min and 20 min before the training, respectively. In experiment 3, rats in diestrus received scopolamine (1 mg/kg) or saline i.p. 20 min before the training, and estradiol valerate (1 mg/kg) or sesame oil i.m. immediately after the training session. In all experiments, a test session was performed 24 h later. The main results showed that: (1) scopolamine impaired retrieval and induced anxiolytic and hyperlocomotor effects in all experiments; (2) this cholinergic antagonist impaired acquisition only in animals in diestrus; (3) acute administration of estradiol valerate prevented the learning impairment induced by scopolamine and (4) interfered with memory consolidation process. The results suggest that endogenous variations in estrogen levels across the estrous cycle modulate some aspects of memory mediated by the cholinergic system. Indeed, specifically in diestrus, a stage with low estrogen levels, the impairment produced by scopolamine on the acquisition was counteracted by exogenous administration of the hormone, whereas the posttraining treatment potentiated the negative effects of scopolamine during the consolidation phase of memory.

Repeated treatment with a low dose of reserpine as a progressive model of Parkinson's disease.

Animal models are widely used to study alterations caused by Parkinson's disease (PD). However, in general, pharmacological models do not express the progressive nature of the disease, being characterized by immediate severe motor impairment after a single dose of the drug. Reserpine administration in rodents has been suggested as a pharmacological model of PD based on the effects of this monoamine-depleting agent on motor activity. Here, we describe that repeated administration with a low dose (0.1 mg/kg) of reserpine in rats induces a gradual appearance of motor signs, evaluated by catalepsy behavior. Furthermore, these motor signs are accompanied by increased levels of striatal lipid peroxidation. However, treatment with reserpine failed to induce memory impairments (evaluated by novel object recognition and discriminative avoidance tasks) and alterations in hippocampal lipid peroxidation. Thus, repeated treatment with low doses of reserpine progressively induces alterations in motor function and an increase in striatal oxidative stress, indicating a possible application of this model in the study of the neuroprogressive nature of the motor signs in PD.

Antidepressants differentially modify the extinction of an aversive memory task in female rats.

Treatment of major depression, posttraumatic stress disorder and other psychopathologies with antidepressants can be associated with improvement of the cognitive deficits related to these disorders. Although the mechanisms of these effects are not completely elucidated, alterations in the extinction of aversive memories are believed to play a role in these psychopathologies. We have recently verified that female rats present low levels of extinction when submitted to the plus-maze discriminative avoidance task. In the present study, female rats were treated long term with clinically used antidepressants (fluoxetine, nortriptyline or mirtazapine) and subjected to the plus-maze discriminative avoidance task to evaluate learning, memory, extinction and anxiety-related behaviors as well as behavioral despair in the forced swimming test. All groups learned the task and exhibited retrieval. Chronic treatment with fluoxetine (but not with the other antidepressants tested) increased extinction of the discriminative task. In the forced swimming test, the animals treated with fluoxetine and mirtazapine showed decreased immobility duration. In conclusion, fluoxetine potentiated extinction, while both fluoxetine and mirtazapine were effective in ameliorating depressive-like behavior in the forced swimming test, suggesting a possible dissociation between the effects on mood and the extinction of aversive memories in female rats.

Sex differences in aversive memory in rats: possible role of extinction and reactive emotional factors.

Studies usually show better spatial learning in males and stronger emotional memory in females. Spatial memory differences could relate to diverse strategies, while dissimilar stress reactions could cause emotional memory differences. We compared male and female rats in two emotional (classical emotional conditioning and aversive discrimination memory) and two emotionally "neutral" tasks: (1) plus-maze discriminative avoidance, containing two open and two enclosed arms, one of which presenting aversive stimuli (light/noise). No differences were found in learning, retrieving, or basal emotional levels, while only male rats presented extinction of the task; (2) contextual fear conditioning--a cage was paired to mild foot shocks. Upon reexposure, freezing behavior was decreased in females; (3) spontaneous alternation--the animals were expected to alternate among the arms of a four-arm maze. No differences between genders were found and (4) open-field habituation was addressed in an arena which the rats were allowed to explore for 10 min. Habituation was similar between genders. Differences were found only in tasks with strong emotional contexts, where different fear responses and stress effects could be determinant. The lack of extinction of discriminative avoidance by females points out to stronger consolidation and/or impaired extinction of aversive memories.

GABA and opioid mechanisms of the central amygdala underlie the withdrawal-potentiated startle from acute morphine.

Anxiety is an affective symptom common to withdrawal from acute or chronic opiate treatment. Although the potentiation of the acoustic startle reflex has been proposed as an index of increased anxiety, there are variable effects of the opiate withdrawal on the startle reflex in chronic dependence models. On the other hand, withdrawal from acute morphine treatment consistently potentiates the acoustic startle reflex, a response that seems to be mediated by the central nucleus of the amygdala (CeA). However, the underlying neurochemical mechanisms have not been elucidated yet. In the present study, we firstly made a comparison between the effects of the withdrawal from both acute and chronic treatments with morphine on the motor activity and the anxiety-like behavior of rats tested in two experimental models, the acoustic startle reflex and the open-field tests. Our second objective was to investigate the role of GABAergic and opioid mechanisms of the CeA in the modulation of the withdrawal-potentiated startle as a measure of anxiety induced by morphine withdrawal. For the production of chronic dependence, rats received morphine injections (10 mg/kg; s.c.) twice daily during 10 days. Forty-eight hours after the interruption of this treatment, independent groups were probed in the startle reflex and open-field tests. For the acute dependence model, groups of rats were tested in the open field and startle tests under control conditions and under withdrawal from a single injection of morphine (10 mg/kg; s.c.) precipitated by naltrexone injections (0.1 mg/kg; s.c.). The results obtained showed that withdrawal from chronic and acute morphine treatments produced anxiety-like behavior in the open field test, although the anxiogenic-like effects could not be dissociated from the motor effects in the acute dependence model. On the other hand, only the withdrawal from acute morphine treatment significantly potentiated the startle response. Next, we examined the effects of intra-CeA microinjections of muscimol-a GABA(A) receptors agonist-and DAMGO-a mu-opioid receptors agonist-on the potentiated startle induced by acute morphine withdrawal. The results obtained showed that intra-CeA injections of muscimol (1 nmol) and DAMGO (0.5 and 1 nmol) significantly inhibited this response. These findings suggest that the acute dependence model is more suitable to study the aversive effects of morphine withdrawal on the acoustic startle response than the chronic opiate dependence model. Besides, mechanisms mediated by mu- and GABA(A)-receptors in the CeA appear to exert an inhibitory influence on the anxiety-like behavior induced by withdrawal from acute morphine treatment.

Involvement of the midbrain tectum in the unconditioned fear promoted by morphine withdrawal.

The midbrain tectum structures, dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), are involved in the organization of fear and anxiety states during the exposure to dangerous stimuli. Since opiate withdrawal is associated with increased anxiety in both humans and animals, this study aimed to investigate the possible sensitization of the neural substrates of fear in the midbrain tectum and its influence on the morphine withdrawal-induced anxiety. For the production of drug withdrawal, rats received morphine injections (10 mg/kg; s.c.) twice daily during 10 days. Forty-eight hours after the interruption of the chronic treatment, independent groups were probed in the elevated plus-maze and open-field tests. Additional groups of animals were implanted with a bipolar electrode into the dPAG or the IC and submitted to the electrical stimulation of these structures for the determination of the freezing and escape thresholds after 48 h of withdrawal. Our results showed that the morphine withdrawal promoted clear-cut levels of anxiety without the somatic signs of opiate withdrawal. Moreover, morphine-withdrawn rats had an increase in the reactivity to the electrical stimulation of the dPAG and the IC. These findings suggest that the increased anxiety induced by morphine withdrawal is associated with the sensitization of the neural substrates of fear in the dPAG and the IC. So, the present results give support to the hypothesis that withdrawal from chronic treatment with morphine leads to fear states possibly engendered by activation of the dPAG and IC, regardless of the production of somatic symptoms.

Effects of tactile stimulation and underwater trauma on the behavior of protein-malnourished rats in the elevated plus-maze test

The objective of the present study was to evaluate the interaction of two kinds of external stimuli (long-term tactile stimulation and underwater trauma) on the exploratory behavior of malnourished rats in an elevated plus maze (EPM). The results showed that tactile stimulation partially recovered body weight deficits produced by malnutrition and decreased EPM exploration. Malnutrition increased EPM exploration while underwater trauma decreased it, thus reducing differences between well nourished and malnourished animals. These data show that only one of the two external stimuli (underwater trauma) interacted with diet condition, suggesting that the stress caused by trauma was efficient in decreasing higher EPM exploration, equalizing the response of malnourished animals to that of non-traumatized well-nourished animals.

Effects of tactile stimulation and underwater trauma on the behavior of protein-malnourished rats in the elevated plus-maze test

The objective of the present study was to evaluate the interaction of two kinds of external stimuli (long-term tactile stimulation and underwater trauma) on the exploratory behavior of malnourished rats in an elevated plus maze (EPM). The results showed that tactile stimulation partially recovered body weight deficits produced by malnutrition and decreased EPM exploration. Malnutrition increased EPM exploration while underwater trauma decreased it, thus reducing differences between well nourished and malnourished animals. These data show that only one of the two external stimuli (underwater trauma) interacted with diet condition, suggesting that the stress caused by trauma was efficient in decreasing higher EPM exploration, equalizing the response of malnourished animals to that of non-traumatized well-nourished animals.(AU)

Brainstem areas activated by diazepam withdrawal as measured by Fos-protein immunoreactivity in rats.

In the 1970s, chronic treatment with benzodiazepines was supposed not to cause dependence. However, by the end of the decade several reports showed that the interruption of a prolonged treatment with diazepam leads to a withdrawal syndrome characterized, among other symptoms, by an exaggerated level of anxiety. In laboratory animals, signs that oscillate from irritability to extreme fear-like behaviors and convulsions have also been reported. In recent years many studies have attempted to disclose the neural substrates responsible for the benzodiazepines withdrawal. However, they have focused on telencephalic structures such as the prefrontal cortex, nucleus accumbens and amygdala. In this study, we examined the Fos immunoreactivity in brain structures known to be implicated in the neural substrates of aversion in rats under spontaneous diazepam-withdrawal. We found that the same group of structures that originally modulate the defensive responses evoked by fear stimuli, including the dorso-medial hypothalamus, the superior and inferior colliculus and the dorsal periaqueductal gray, were most labeled following diazepam withdrawal. It is suggested that an enhanced neural activation of neural substrates of fear in the midbrain tectum may underlie the aversive state elicited in diazepam-withdrawn rats.