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The lateral hypothalamus (LH) is a main component of the brain’s reward circuit. Previous studies have shown that high-frequency deep brain stimulation (DBS) of the LH prevents morphine-induced place preference in rats. In the present study we evaluated the effect of intra-LH DBS on the levels of dopamine receptors in the prefrontal cortex.

Electrodes were implanted into the LH bilaterally. Rats were allocated to four different groups: morphine-DBS, saline-DBS, morphine-sham, and saline-sham. Morphine (5mg/kg.sc) and saline were given in four consecutive days immediately followed by DBS (130 Hz pulse repetition frequency, 150 µA pulse amplitude, and 100 μs pulse width) or sham-DBS for 30 min corresponding to the experimental group. One day after the last injection rats were sacrificed and the prefrontal cortex was dissected for assaying dopamine receptors and c-fos mRNA expression.

Morphine increased D1 receptor, decreased D2 receptor, and had no effect on D3, D4, and D5 receptors. DBS in morphine-treated rats prevented the elevation of D1 receptor, increased D2 and D3 receptors, decreased D5 receptor, and had no effect on D4 receptors. Morphine decreased c-fos mRNA levels in the prefrontal cortex and DBS increased it.

DBS of LH influenced the brain’s dopaminergic system particularly in the prefrontal cortex.

Central γ-aminobutyric acid (GABA) neurotransmission modulates cardiovascular functions and sleep. Acute sleep deprivation (ASD) affects functions of various body organs via different mechanisms. Here, we evaluated the effect of ASD on cardiac ischemia/reperfusion injury (IRI), and studied the role of GABA-A receptor inhibition in central nucleus of amygdala (CeA) by assessing nitric oxide (NO) and oxidative stress.
The CeA in sixty male Wistar rats was cannulated for saline or bicuculline (GABA-A receptor antagonist) administration. All animals underwent 30 min of coronary occlusion (ischemia), followed by 2 hr reperfusion (IR). The five experimental groups (n=12) included are as follows: IR: received saline; BIC: received Bicuculline; MLP: received saline, followed by the placement of animals in an aquarium with multiple large platforms; ASD: underwent ASD in an aquarium with multiple small platforms; and BICĠ︡: received bicuculline prior to ASD.
Bicuculline administration increased the malondialdehyde levels and infarct size, and decreased the NO metabolites levels and endothelial nitric oxide synthase (eNOS) gene expression in infarcted and non-infarcted areas in comparison to IR group. ASD reduced malondialdehyde levels and infarct size and increased NO metabolites, corticosterone levels and eNOS expression in infarcted and non-infarcted areas as compared to the IR group. Levels of malondialdehyde were increased while levels of NO metabolites, corticosterone and eNOS expression in infarcted and non-infarcted areas were reduced in the BICĠ︡ as compared to the ASD group.
Blockade of GABA-A receptors in the CeA abolishes ASD-induced cardioprotection by suppressing oxidative stress and NO production.

In the present study the effect of stress on monkeys that had learned to retrieve food from a five-chamber receptacle, as well as the relationship between their behavior and the serum cortisol and epinephrine levels and relative size of the amygdala was evaluated.
Six male rhesus monkeys were individually given access to the food reward orderly. They could easily retrieve the rewards from all chambers except for the chamber 4, which a brief, mild electric shock (3 V) was delivered to them upon touching the chamber’s interior. The coping behaviors were video-recorded and analyzed offline. Baseline serum cortisol and epinephrine levels were measured before the experiments using monkey enzyme-linked immunosorbent assay kit. One week after the behavioral experiment, the monkeys’ brains were scanned using magnetic resonance imaging under general anesthesia. The cross-sectional area of the left amygdala in sagittal plane relative to the area of the whole brain in the same slice was evaluated by the planimetric method using ImageJ software.
Exposure to the distressing condition caused different behavioral responses. Monkeys with higher baseline levels of serum cortisol and epinephrine and larger amygdala behaved more violently in the face of stress, indicating adopting emotion-focused stress-coping strategies. Conversely, those with low plasma epinephrine, moderate cortisol, and smaller amygdala showed perseverative behavior, indicating a problem-focused coping style.
In dealing with the same stress, different responses might be observed from nonhuman primates according to their cortisol and epinephrine levels as well as their amygdala dimensions.

An exact histologic staging of liver fibrosis is essential for identifying the best therapeutic strategy and determining the disease prognosis in patients with chronic hepatitis B (CHB). While liver biopsy has a vital role in the management of liver diseases, it also sustains some limitations hampering its widespread use.. In this study, we evaluated and compared several available indices of the severity of liver diseases in patients with hepatitis..Patients and Exclusion criteria were as follows: decompensated liver disease, alcoholic liver disease or alcohol intake of 40 g or more per week; co-infection with human immunodeficiency virus, hepatitis C virus, or hepatitis D virus.. Results showed that AST to platelet ratio index (APRI) (odds ratio = 2.35, P = 0.01) and age (odds ratio = 1.04, P = 0.007) were independently predictive of the presence of significant liver necrosis and inflammation. On the other hand, AARPRI (odds ratio = 3.8, P = 0.07), age (odds ratio = 1.04, P = 0.02), and ALT levels (odds ratio = 1.01, P = 0.007) were predictive of a significant liver fibrosis. Further analysis with receiver-operating curve showed that none of these predictors had a fair diagnostic value (area under the curve < 70).. The APRI had the highest sensitivity and specificity (64% and 71%, respectively) for prediction of the presence of liver disease. We suggest that APRI may be applicable for the detection of a severe liver disease..