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Renin-angiotensin system as an important regulator of renal function has also a major role in inflammation. In the present study, the effects of captopril on renal dysfunction, renal cytokine levels, and renal tissue oxidative damage were investigated in lipopolysaccharide (LPS)-induced inflammation model in rats. Treatment of five groups of the rats was carried out as follows: (1) saline as a control, (2) LPS 1 mg/kg, and (3–5) 10, 50, or 100 mg/kg captopril 30 min, respectively, before LPS. The treatments were given for 12 days. Finally, the animals were deeply anesthetized, the blood samples were obtained, and the renal tissues were removed and kept for biochemical measurements. Administration of LPS increased serum blood urea nitrogen and creatinine (P < 0.001). Pretreatment with all doses of captopril decreased these parameters (P < 0.001). LPS also increased interleukin-6 (IL-6), malondialdehyde, and nitric oxide metabolites in the renal tissues (P

The effects of tamoxifen (TAM) on anxiety and depression-like behavior in ovariectomized (OVX) and naïve female rats were investigated. The animals were divided into Sham-TAM, OVX-TAM, Sham and OVX groups. Tamoxifen (1 mg/kg) was administered for 4 weeks. In the forced swimming test, the immobility times in the OVX and Sham-TAM groups were higher than in the Sham group. In the open field, the numbers of central crossings in the OVX and Sham-TAM groups were lower than the number in the Sham group, and the number of peripheral crossings in the OVX group was lower than the number in the Sham group. In the elevated plus maze, the numbers of entries to the open arm among the animals in the Sham-TAM and OVX groups were lower than the number in the Sham group, while the number of entries to the open arm in the OVX-TAM group was higher than the number in the OVX group. It was shown that deletion of ovarian hormones induced anxiety and depression-like behavior. Administration of tamoxifen in naïve rats led to anxiety and depression-like behavior that was comparable with the effects of ovarian hormone deletion. It can be suggested that tamoxifen antagonizes the effects of ovarian hormones. It also seems that tamoxifen has anxiolytic effects on ovariectomized rats.

Background: The nucleus accumbens (NAc) is a part of the rewarding cortico-mesolimbic dopamine (DA) pathway. This is a heterogeneous structure divided in two sub regions termed core and shell. DA function in the NAc is critical for goal-oriented behaviors, including those motivated by drug and brain stimulation reward. In the conditioned-place preference (CPP) paradigm, a test assessing animal′s ability to associate drug-induced effects with environmental cause to quantify drug reward for example morphine. Methods: In the present study, we investigated the influence of electrical stimulation with different current intensities on (25 and 100 µA) with and without an effective dose of morphine (0.5 and 5 mg/kg) on CPP. Results: Subcutaneous administration of morphine 5 mg/kg produced significant CPP in comparison with saline group. Our findings also showed that electrical stimulation of NAc (100 µA) significantly (P < 0.01) suppressed morphine-induced CPP that reveals impaired learning and memory formation in the process of conditioning. We found that morphine-induced CPP can be successfully suppressed by current intensity (100 µA). It was probably due to decreasing of dopamine contents and its metabolites in the NAc. Current intensity (100 µA) in combination with ineffective dose of morphine (0.5 mg/kg) increased morphine-induced CPP probability via the prove reward system. Conclusions: Since stimulation of dopaminergic neurons increases tendency to dependence to morphine, therefore in the present study, the stimulation of the NAc suppressed morphine-induced CPP that this shows impairment of learning and memory formation.

Objective(s): Drug addiction is one of the fastest growing social problems that researchers, for many years, have been trying to find proper strategies for its prevention and treatment. Short-term physical activity is considered as acceptable for the treatment and prevention of addiction. On the other hand, prefrontal cortex is known to be responsible for many of the complex behavioral responses, especially those relevant to addiction and drug abuse. In this study, the effects of short-term physical activity (treadmill running) on withdrawal symptoms in rats, with or without medial Prefrontal Cortex (mPFC) area was evaluated. Materials and Methods: In this experimental study, male Wistar rats, weighing 250-300 g. Were selected and divided into four groups: control, sham, test1 and test 2 groups, with one group having a surgery (test 2). In order to study the effects of short-term physical activity, we employed a treadmill with the adjustable speed of 17 m/min, and a 15% incline. Following the injection of three different doses of morphine (10, 20 and 40 mg/Kg) for 9 days, treadmill running was completed on the tenth day and then the symptoms of addiction were evaluated. Results: Administration of morphine as aforementioned, and treadmill running on rats with mPFC area, significantly alleviated some of the symptoms and signs, such as, bruxism, cycling, body lift, licking, standing and scratching (P

Background: Drug addiction is one of the social damages that researchers have tried to find suitable strategies for prevention and treatment of it. Meanwhile, short-term physical activity is acceptable parameter for treatment and prevention of addiction. On the other hand, prefrontal cortex, for a long time as mediating, is involved in many of the complex behavioral responses, especially those associated with addiction and drug abuse. In this paper, the effects of short-term physical activity (treadmill running) on withdrawal symptom with or without mPFC area have been evaluated. Methods: This experimental study was done on Wistar rats weighing 250 ± 300 g separated to four groups: control, shame, test 1 and test 2; one of the test groups had surgery and lesion on mPFC area. For studying the effects of short-term physical activity, we used treadmill with adjustable speed of 17 m/minute and a 15-degrees slope; after the injection of three doses of morphine, 10, 20, 40 mg in 9 days and running on the treadmill, in the tenth day, the symptoms of addiction were evaluated. Findings: The morphine injection and running on the treadmill without mPFC region destruction tended to decreasing morphine tendency. There was a significant difference between the rats, with or without mPFC area, received morphine but did not run on the treadmill in morphine tendency (P < 0.05). Conclusion: It seems that short-term physical activity (treadmill running) decreases the tendency of using morphine with mPFC area in comparison with other groups, especially with group operated in their mPFC area.

The effects of a high estradiol dose on memory and on nitric oxide metabolites in hippocampal tissues were investigated. Sham-Est and OVX-Est Groups were treated with 4 mg/kg of estradiol valerate for 12 weeks. Time latency and path length were significantly higher in the Sham-Est and OVX-Est Groups than in the Sham and OVX Groups, respectively (p

Different effects of scopolamine on learning, memory, and nitric oxide (NO) metabolites in hippocampal tissues of ovariectomized (OVX) and sham-operated rats were investigated. The animals in the Sham-Scopolamine (Sham-Sco) and OVX-Scopolamine (OVX-Sco) Groups were treated with 2 mg/kg scopolamine before undergoing the Morris water maze, while the animals in the Sham and OVX Groups received saline. The time latency and path length were significantly higher in both the Sham-Sco and the OVX-Sco Groups, in comparison with the Sham and OVX Groups, respectively (p

Objective: Parkinson's disease (PD) is one of the most common neurodegenerative disorders which is characterized by tremor, rigidity, bradykinesia and postural disturbances. Studies indicate that grape juice and exercise may have beneficial effects on neurodegenerative disorders. Therefore, in the present study, we evaluated the effects of red grape juice (GJ) together with treadmill running on animal model of PD. Materials and Methods: 30 male Wistar rats were divided randomly into Sham, PD, PD treated with GJ (PD-GJ), PD treated with exercise (PD-Ex), and PD treated with GJ associated with exercise (PD-GJ-Ex) groups with six rats in each. In order to obtain the PD model, 6-OHDA was infused into left substantia nigra pars compacta. In order to prove that the lesions are created and to estimate their extent, apomorphine was administered (i.p.) and total number of induced rotations was recorded during 60 minutes. Exercise was applied by treadmill and GJ was added into drinking water for 30 days and rotations test was performed again. Results: Our results indicate that there was a significant difference in number of rotations between PD and Sham groups (p

INTRODUCTION: The role of ovarian hormones and nitric oxide in learning and memory has been widely investigated. OBJECTIVE: The present study was carried out to evaluate the effect of the nitric oxide synthase (NOS) inhibitor, N (G)-nitro-L-arginine methyl ester (L-NAME), on the ability of estradiol to improve learning in OVX rats using the Morris water maze. METHODS: Forty rats were divided into five groups: (1) ovariectomized (OVX), (2) ovariectomized-estradiol (OVX-Est), (3) ovariectomized-L-NAME 10 (OVX-LN 10), (4) ovariectomized-L-NAME 50 (OVX-LN 50) and (5) ovariectomized-estradiol-L-NAME 50 (OVX-Est-LN 50). The animals in the OVX-Est group were treated with a weekly injection of estradiol valerate (2 mg/kg; i.m.). The OVX-LN 10 and OVX-LN 50 groups were treated with daily injections of 10 and 50 mg/kg L-NAME (i.p.), respectively. The animals in the OVX-Est-LN 50 group received a weekly injection of estradiol valerate and a daily injection of 50 mg/kg L-NAME. After 8 weeks, all animals were tested in the Morris water maze. RESULTS: The animals in the OVX-Est group had a significantly lower latency in the maze than the OVX group (p

Neuroimmune factors have been proposed as the contributors to the pathogenesis of sickness behaviors. The effects of female gonadal hormones on both neuroinflammation and depression have also been well considered. In the present study, the capability of deletion of ovarian hormones to induce sickness-like behaviors in rats was compared with the effect lipopolysaccharide (LPS). The groups were including Sham, OVX, Sham-LPS, and OVX-LPS. The Sham-LPS and OVX-LPS groups were treated with LPS (250 μg/kg) two hours before conducting the behavioral tests. In the forced swimming (FST), the immobility times in both OVX and Sham-LPS groups were higher than that of Sham (P

The current research is qualitative research that was conducted using the synthesis research method based on the deductive model. The research environment in the synthesis phase included all citations in the range of 2008 to 2020 for the studies conducted in the field of experimental science education of the second grade in elementary school. Based on this, 40 sources were selected by purposive selection method. Stopping the sampling process was based on information saturation. Data collection was done using a survey in the research environment and based on the synthesis of experimental science education in the second grade of primary school. According to the findings of the research synthesis based on the deductive model, the environmental factors affecting experimental science education in the second grade of primary school include: support factors (family-oriented, school-oriented), extracurricular environment, socio-cultural environment, science curriculum design including goals (instructional, educational, motivational), content (knowledge, practical skills, challenging thinking), teaching strategies (group discussion, advance organizer, exploration, problem solving, learning assistants, laboratory, cognitive development, game-oriented, aesthetic), intra-school environment (independent, individual, deep, collaborative, exploratory), evaluation (evaluation tools, evaluation methods), learned skills (life skills, mental skills, social skills, thinking skills), science education approaches (teacher-centered, student-centered) and learning experiences (meaningful experiences and valuable experiences). The findings provide useful implications for science education in elementary school and can be used by elementary school teachers and parents for science education as well.

Abstract It has been shown that the activity of some neurotransmitters may be changed by exercise. It can also affect on pleasure center through Opioid Systems and releasing neurotransmitters. Based on the effect of exercise, in this research, we studied the effect of exercise and physical activity with treadmill running on spatial learning and memory in the intact and morphine dependent male rats. Background: Healthy male Wistar rats ,weighting about 250gr 4 month age , were divided into four groups as follows: control (without treadmill running and morphine) , exercise (treadmill running and without morphine) , morphine (morphine treatment without treadmill running) and exercise+morphine treatment (n=10). Compulsive running on rat treadmill were performed in a ten- days period (1hr per day, at a speed of 17m/min and an incline of 15 degrees). Intraperitoneal injection of dissolved morphine with increasing doses of 10 mg/kg , 20 mg/kg and 40mg/kg for the first , second and third every 3 days , respectively , were applied to make rats morphine dependence. Corresponding control rats went through spatial learning process on a Morris water maze for 8 days. The time to reach the platform (latency), the length of swim path, and the swim speed were used for the evaluation of spatial learning. Methods: On the basis of this results, in comparison of total mean of the eight days spatial learning and memory experiment, for three parameters (path length, latency and swim speed), between control groups and exercise + morphine treatment groups are significant different (P< 0. 05). The differences of these parameters between exercise + morphine groups with another groups is significant (P0.05). Findings: We found that treadmill running can improve spatial learning and memory in morphine dependent rats significantly. These results confirm with our previously reports. According to effect of exercise on the release of endorphin and activation of neurotransmitters systems such as dopaminergic, serotonergic and glutamatergic, It could be short- term of exercise with opioid system together increase spatial learning and memory in rats morphine dependence, suggesting the pleasure center in the brain is the same for addiction and memory. Conclusion: Exercise, spatial memory, rat, Morris water maze. Key words: