Yawning, associated with genital grooming, is a physiological response that may be used for elucidating the mechanism of action of drugs. Preliminary analysis showed that aqueous extract (AE) of Saccharum induced yawns in rats. So, we aimed to quantify these behavioral responses and investigate the pharmacological mechanisms involved in these actions.
View Article and Find Full Text PDFThe interaction between dopaminergic and cholinergic pathways in the induction of behavioral responses has been previously established. In the brain, M2 receptors are found predominantly in presynaptic cholinergic neurons as autoreceptors, and in dopaminergic neurons as heteroceptors, suggesting a control role of acetylcholine and dopamine release, respectively. Our aim was to investigate the role of M2 receptors on the yawning and genital grooming of rats induced by apomorphine, a dopaminergic receptor agonist, focusing on the interaction between cholinergic and dopaminergic pathways.
View Article and Find Full Text PDFObjectives: The effects of short-term 5-day and long-term 30-day hyperprolactinemia induced by domperidone (1.7 mg/kg/day, s.c.
View Article and Find Full Text PDFObjective: Crime is now a top-priority public-health issue in many urban areas. Sao Paulo's state police force was the target of gunfire attack on an unprecedented scale. Several officers were killed or wounded, and many more were affected by psychological trauma.
View Article and Find Full Text PDFToxocara canis is a common canine nematode parasite and one of its possible transmission mechanisms is the predation of infected rodents by canids. Fifty Rattus norvegicus were used to study behavioral alterations in rodents infected by T. canis larvae.
View Article and Find Full Text PDFBackground/aim: Prolactin (PRL), a hormone produced by the pituitary gland, has multiple physiological functions, including immunoregulation. PRL can also be secreted in response to stressful stimuli. During stress, PRL has been suggested to oppose the immunosuppressive effects of inflammatory mediators.
View Article and Find Full Text PDFThe muscular strength of experimental infected Rattus norvegicus with 3rd. stage Toxocara canis larvae was investigated. Fifty Wistar rats, divided in three groups (G1-20 rats infected by 300 eggs of T.
View Article and Find Full Text PDFThe original aim of psychology was to study and understand the spirit-from the Latin spiritus, literally "breath." The limitations of scientific methods in the past favoured psychology's aloofness in terms of studying the "intangible," while medicine developed methods of examining the body (Latin corpus: essential part). Until 20 years ago, knowledge of the localization of brain functions was limited to inferences from clinical observation of brain-lesioned patients or parallel studies of primate brains.
View Article and Find Full Text PDFObjective: Prolactin (PRL), a peptide hormone produced by the pituitary gland, is involved in the interaction between the neuroendocrine and immune system. Since dopamine receptor antagonists increase serum levels of PRL, both PRL and dopamine receptors might be involved in the modulation of macrophage activity, providing means of communication between the nervous and immune systems. This study evaluated the effects of PRL and the dopamine antagonist domperidone (DOMP) on macrophage activity of female rats.
View Article and Find Full Text PDFIntroduction: In contrast to the impressive advances in somatic research of erectile dysfunction (ED), scientific literature shows contradictory reports on the results of psychotherapy for the treatment of ED.
Aim: Authors conducted a meta-analysis to evaluate the effectiveness of psychological interventions for the treatment of ED compared to oral drugs, local injection, vacuum devices, or other psychological intervention.
Method: Distinct sources of randomized controlled trials (RCTs) were searched: electronic databases (between 1966 and 2007), cross checking of references, and contact with scientific societies.
Objective: Neuroimaging studies have highlighted important issues related to structural and functional brain changes found in sufferers of psychological trauma that may influence their ability to synthesize, categorize, and integrate traumatic memories.
Methods: Literature review and critical analysis and synthesis.
Results: Traumatic memories are diagnostic symptoms of post-traumatic stress disorder (PTSD), and the dual representation theory posits separate memory systems subserving vivid re-experiencing (non-hippocampally dependent) versus declarative autobiographical memories of trauma (hippocampally dependent).
Reproductive experience (RE), i.e. pregnancy and lactation, induces physiological changes in mammals.
View Article and Find Full Text PDFAlthough numerous inflammation pathways have been implicated in Alzheimer's disease, the involvement of the kallikrein-kinin system is still under investigation. We anatomically localized and quantified the density of kinin B(1) and B(2) receptors binding sites in the rat brain after the infusion of amyloid-beta (Abeta) peptide in the right lateral brain ventricle for 5 weeks. The conditioned avoidance test showed a significant reduction of memory consolidation in rats infused with Abeta (68.
View Article and Find Full Text PDFBackground: Traumatic memory is a key symptom in psychological trauma victims and may remain vivid for several years. Psychotherapy has shown that neither the psychopathological signs of trauma nor the expression of traumatic memories are static over time. However, few studies have investigated the neural substrates of psychotherapy-related symptom changes.
View Article and Find Full Text PDFCholecystokinin (CCK) and opiates interaction is critical for maintaining maternal behavior during lactation. Morphine inhibits while CCK restores maternal behavior. Recently we have shown that periaqueductal gray (PAG) is a region critically involved in the opioidergic blockade of maternal behavior.
View Article and Find Full Text PDFThe dopaminergic system requires combined dopamine D1/D2 receptor stimulation to express its activity; a phenomenon called synergism D1/D2. Dopamine receptors develop supersensitivity following dopamine de-afferentation and/or reserpine treatment. Acute supersensitivity occurs with reserpine treatment.
View Article and Find Full Text PDFPre-mating treatment of female rats with morphine may have long-term effects. In this study, we analyzed the effects of two types of morphine sulfate pre-treatment: during pre-mating (5.0 mg/kg on alternate days for a total of seven doses) and during pregnancy (3.
View Article and Find Full Text PDFPsychol Psychother
December 2005
The search to understand response to trauma has turned to the contribution of personality factors. The way people process the stressor event is critical in determining whether a trauma will be configured or not. Neuroscience shows that the brain does not store memories, but traces of information that are later used to create memories, which do not always express a completely factual picture of the past experience.
View Article and Find Full Text PDFPsychopharmacology (Berl)
June 2005
Sudden darkness is a non-invasive behavioural analysis tool which increases motor activity and decreases anxiety in rats. It has been shown in previous studies that in rats, dark test conditions can also modify behavioural responses to drugs acting on the dopaminergic system. The increasing use of transgenic mice in behavioural research has raised interest in developing new tests for phenotyping mice.
View Article and Find Full Text PDFAlthough adrenocorticotropic hormone is generally considered to play a major role in the regulation of adrenal glucocorticoid secretion, several reports have suggested that other pituitary hormones (e.g., prolactin) also play a significant role in the regulation of adrenal function.
View Article and Find Full Text PDFPharmacol Biochem Behav
July 2003
Drug-induced inhibition of plasma and tissue cholinesterase activity was evaluated in rats. The dopamine receptor antagonists haloperidol (HALO), chlorpromazine (CPZ), thioridazine (THIO), fluphenazine (FLU), clozapine (CLO) and sulpiride (SULP), used as neuroleptics, were tested. Two biochemical parameters were measured in vitro: the minimal effective concentration (MEC) for cholinesterase inhibition and the 50% inhibitory concentration (IC50).
View Article and Find Full Text PDFSudden darkness increases motor activity and decreases anxiety. In the present study, we focused on the role of dopaminergic mechanisms involved in the effects of sudden darkness. The influence of sudden darkness on the behavioral effects of low (0.
View Article and Find Full Text PDFBlockade of cholecystokinin (CCK) receptors potentiates the morphine-induced disruption of maternal behavior. The present study was undertaken to determine whether treatment with lorglumide, a CCK1 antagonist during late pregnancy and early lactation can influence the maternal behavior during lactation. A possible influence of this treatment on general activity was also assessed.
View Article and Find Full Text PDFBraz J Med Biol Res
November 2001
This article is a transcription of an electronic symposium held on November 28, 2000 in which active researchers were invited by the Brazilian Society of Neuroscience and Behavior (SBNeC) to discuss the advances of the last decade in the peptide field with particular focus on central actions of prolactin and cholecystokinin. The comments in this symposium reflect the diversity of prolactin and cholecystokinin research and demonstrate how the field has matured. Since both peptides play a role in reproductive behaviors, particularly mother-infant interactions, this was the starting point of the discussion.
View Article and Find Full Text PDFOngoing maternal behavior in rats is under the inhibitory influence of opiates. Exposure to drugs of abuse may result in a progressive and enduring enhancement of their reinforcing effects. Little attention has been paid to the possibility that puerperal treatment with morphine may lead to sensitization to this drug, ultimately influencing the effects of opiates on maternal behavior.
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