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Exercise is an essential component in the management of multiple sclerosis (MS). The purpose of this study was to evaluate the effect of a combined aerobic and resistance training programme on muscular strength, static and dynamic balance and resiliency of women with MS. Twenty participants aged 20-40 years with an expanded disability status Scale Level of 2 to 5 were selected. Participants were randomly divided into two groups: Experimental Group (age=36.1±2.2 years) and Control Group (age=34.3±5.4 years). The experimental group performed combination training that included aerobic and resistance exercises for eight weeks, three times a week, with an intensity of 40% to 55% heart rate reserve. The strength of knee flexor and extensor muscles, dynamic and static balance and resiliency level using Connor-Davidson were assessed. There were significant (p=0.05) changes in all measured parameters for the Intervention Group, no significant (p>0.05) changes were found from pre- to post-test in the Control Group. Eight weeks of combined training improved significantly (p=0.05) for muscle strength, balance and resiliency level in the Experimental Group when compared to the Control Group. Combined training may inevitably aid daily functioning and mental health in individuals with MS. [ABSTRACT FROM AUTHOR]

Introduction: Memory and cognitive impairments are some of devastating outcomes of Multiple Sclerosis (MS) plaques in hippocampus, the gray matter part of the brain. The present study aimed to evaluate the intrahippocampal injection of Ethidium Bromide (EB) as a simple and focal model to assess cognition and gray matter demyelination. Methods: Thirty Wistar rats were divided into three groups: control group, which received saline, as solvent of EB, into the hippocampus; and two experimental groups, which received 3 µL of EB into the hippocampus, and then, were evaluated 7 and 28 days after EB injection (n=10 in each group), using a 5-day protocol of Morris Water Maze (MWM) task as well as Transmission Electron Microscopy (TEM) assay. Results: Seven days after EB injection, the behavioral study revealed a significance increase in travelled distance for platform finding in the experimental group compared to the control group. In addition, the nucleus of oligodendrocyte showed the typical clumped chromatin, probably attributed to apoptosis, and the myelin sheaths of some axons were unwrapped and disintegrated. Twenty-eight days after EB injection, the traveled distance and the time spent in target quadrant significantly decreased and increased, respectively in experimental groups compared to the control group. Also, TEM micrographs revealed a thin layer of remyelination around the axons in 28 days lesion group. Discussion: While intracerebral or intraventricular injection of EB is disseminated in different parts of the brain and can affect the other motor and sensory systems, this model is confined locally and facilitates behavioral study. Also, this project could show improvement of memory function subsequent to the physiological repair of the gray matter of the hippocampus. [ABSTRACT FROM AUTHOR]

Objective(s): The relationship between tramadol, as an antinociceptive drug, and locus coeruleus (LC), the main noradrenergic nucleus of the brain that affects regulation and modulation of pain through descending noradrenergic pathways was investigated. Materials and Methods: Male Sprague-Dawley rats were divided into four groups of 10 rats. The rats were fixed in stereotaxic instrument and then a probe was inserted into LC. Pain was induced by subcutaneous injection of 5 0 μl of 2.5% formalin 40 minutes after initiation of microdialysis in right hind paw, and nociceptive pain scores were calculated every 5 minutes. Subsequently noradrenaline (NA) and its metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG), were collected and measured by microdialysis of locus coeruleus in freely moving rats every 15 minutes during formalin injection. Results: Nociceptive pain scores observed in formalin test had the highest nociceptive sensation 5 minutes after injection. Significant rises in concentrations of NA and MHPG, in samples taken between 30 and 45 min after initiation of the locus coeruleus microdialysis, coincided with the peak of the pain after injection of formalin. Conclusion: According to concurrency of the highest nociceptive sensation and peak of NE and MHPG concentrations, tramadol can indirectly affect the LC by blocking the pain signals from different parts of the brain such as periaqueductal gray mater, central nucleus of amygdale or the spinal cord. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies have suggested that the cerebellum is a primary site of motor learning. The cerebellar cortex has a particular glial architecture with large astroglial cells. In addition, more recent works have revealed that astrocytes play a more active role in neuronal activity. The aim of this study was to evaluate the number of astrocytes in the molecular layer of rat's cerebellum after spatial learning. Methods: 21 male albino wistar rats were used in this study. Reference and working memory methods of Morris Water Maze (MWM) were used. Following behavioral testing, animals were decapitated under diethyl ether anesthesia. Brains were removed and fixed for 2 weeks for histological assessment. Finally, 7 µm thick coronal slices were cut and stained with PTAH staining for showing the astrocytes. Results: Our results showed a significant difference in the number of astrocytes between the control, reference and working memory groups. On the other hand, the number of astrocytes in the working memory group was more than the other groups. There was no difference in density of astrocytes between the lateral and medial parts of the cerebellum in any group. It seems that the distribution of astrocytes in the lateral and medial parts of cerebellum is similar. Discussion: We concluded that spatial learning such as reference or working memory methods, can increase the number of astrocytes in the cerebellum and this increase is similar in the cerebellar cortex. [ABSTRACT FROM AUTHOR]

Objectives: Many studies have focused on ventral tegmental area than of other mesocorticolimbic areas, and implicated a key role for the medial prefrontal cortex (mPFC) in the development of addictive behaviors. So far, the role of gamma-aminobutyric acid (GABA) receptors in the discriminative properties of morphine has received little attention and few studies evaluated the role of these receptors in drug dependence. Hence, we investigated the role of this receptor on morphine- induced GABA/ glutamate (GLU) changes in the mPFC following morphine administration using in vivo microdialysis., Materials and Methods: In this study, 60 rats weighing 270-300 g were divided into six groups. First, microdialysis probe was inserted into the mPFC and was perfused with artificial cerebrospinal fluid and collected the baseline samples in all groups. In saline and morphine groups, the saline, in phaclophen and (phaclofen+morphine) groups, phaclofen (100 nmol), and in bicuculline and (bicuculline+morphine) groups, bicuculline (20 nmol) was injected intracerebroventricular. In saline, phaclofen and bicuculline groups 20 min later, animals received saline (0.2 ml, IP) and others groups received morphine (20 mg/kg, IP)., Results: Our results showed that morphine increased the average concentration of GABA and decreased the concentration of GLU within mPFC. Pretreatment with phaclofen and bicuculline 20 min before morphine administration had no effect on GABA and GLU release for 100 min., Conclusion: The present study indicated that morphine influence the GABA and GLU transmission in mPFC. Therefore evaluation of neurochemistry changes of this neural circuitry may provide further insight into the mechanisms underlying drug dependence., Competing Interests: The authors declare that they have no conflict of interest.

The hippocampal system plays an important role in memory function. Neurohormones like androgens and estrogens that syntheses in hippocampus have an important role in learning and memory. Many biological effects of estrogens in the brain via estrogenic receptors (ERs) are investigated. The current research has conducted to assess the effect of estrogenic receptors on spatial discrimination in rats by using Morris water maze (MWM) task. Adult male rats were bilaterally cannulated into CA1 region of hippocampus and divided in to 9 groups. Different groups received dimethyl sulfoxide (DMSO) 0.5 μl as control groups and different doses of tamoxifen (TAX) as antagonist of ER (0.0625, 0.125 and 0.25μg/0.5μl), propyl pyrazol thiol (PPT) as agonist of ERα (5,10 and 20μg/0.5μl), TAX 0.25μg/0.5μl + PPT 20μg/0.5μl all days 30-35 min before training. Our results have shown TAX (0.25μg/0.5μl), PPT (20μg/0.5μl), TAX (0.25μg/0.5μl) + PPT (20μg/0.5μl) groups significantly increase the escape latency and traveled distance to find invisible platform. Our results indicate that TAX and PPT and also TAX (0.25μg/0.5μl) + PPT (20μg/0.5μl) impaired acquisition of spatial learning and memory. As a consequence, it seems that estrogen modulates memory function via a novel estrogenic mechanism.