جستجوی مقالات مرتبط با کلیدواژه « محرومیت غذایی » در نشریات گروه « پزشکی »

Food deprivation increases the expression of orexin-1 receptor gene in the hypothalamus. On the other hand, food deprivation induces analgesia and orexin has a fundamental and well known role in pain modulation. This study aimed to determine the role of orexin receptor 1 antagonist in analgesic effect of acute food deprivation (12 h) by hot plate test in male rats.
Male Wistar rats were divided into 5 groups (n=8), control, food deprivation without surgery, stereotaxic surgery with vehicle, vehicle and food deprivation and food deprivation and orexin receptor 1 antagonist groups. 12 hours before the hot plate test, food was removed from the animals’ proximity, but water was freely available. All groups were tested using the hot plate. Data were analyzed statistically by one-way ANOVA with Tukey post hoc test.
According to our findings, orexin receptor 1 antagonist injection increased pain related behaviors at the time of 5(P Orexin plays an important role in feeding state–induced pain modulation. Based on our results, change in pain behavior induced by food deprivation may be related to change in orexin expression or in orexin receptors density.

Investigating effects of stress in animal models may suggest clinical treatments or prevention protocols for effects of stress in humans. The aim of this study was to determine the histological effects of chronic multiple stress on rat ovary. This experimental study was conducted in 18 adult female Wistar rats that were randomly divided into two equal groups in Qazvin University of Medical Sciences during 2014. The mice were exposed to different stress including food deprivation, water deprivation, immobility at 4 º c, forced swimming, and isolation for 10 days in the under stress group while the mice in the control group were kept in their cages without any intervention. After the intervention period, the mice were anesthesized, the ovary of the animals were removed and weighed, and the ovary samples were prepared for light microscopic study. The number and diameter of corpus luteum, and the number of antral and preantral follicles were determined using Image Tool software. Data were analyzed using T-test. The mean number and diameter of corpus luteum significantly reduced in the under stress group compared to the control group. The mean number of antral and preantral follicles significantly reduced in the under stress group compared to the control group. With regards to the results, it seems that chronic multiple stress can have negative effects on rat ovary by reducing the diameter and number of corpus luteum and the number of antral and preantral follicles.

Findings represent the role of social stress in aging, disease and mortality of individuals. Since the body responses to environmental stress by anxiety behaviors, in this study we compare the effects of "food restriction", "food deprivation" and "social inequality" on anxiety-like behaviors. 48 male rats were divided into 6 groups including “control”, “food restriction;40% reduction of food intake;beeing able to sense other’s feeding(inequality)”, “food restriction keeping in isolated place (without inequality)”, “intermitant food restriction”, “food deprivation; 70% reduction in food intake; beeing able to sense other’s feeding(inequality)”, and “food deprivation keeping in isolated place (without inequality)”. Different enviromental stresses was applied during three weeks. At the end of stress period anxiety behavior was measured by elevated plus maze(EPM) test. Results and The duration and frequency of open arm entries in food deprivation groups had a significant increase and in food restriction groups had a significant decrease compared to the control group.Combination of Increasing activity of the animals with anxiety during Dietry restriction along with food inequality represent the effort conditions of animals for improvement. Food deprivation reduces activity, especially when is combined with the feeling of inequality that can be considered as the probable role of social inequality in manifestation of a “learned helplessness” situation

It is well recognized that gender and race differences play a role in pain sensitivity، pain perception، response to analgesic drug and prevalence of certain chronic pain disorders. In this study investigated gender and strain-related differences in the effect of food deprivation on formalin induced nociceptive behaviors in rats. This study was done in Qazvin University of Medical Sciences 8 groups of rats (220-300gr). Groups 1 and 2: Effect formalin-induced nociceptive behaviours in male and female Sprague-Dawley rats. Groups 3 and 4: Effect formalin-induced nociceptive behaviours in male and female Wistar rats. Groups 5 and 6: Effect of food deprivation on formalin-induced nociceptive behaviours in male and female Sprague-Dawley rats. Groups 7 and 8: Effect of food deprivation on formalin-induced nociceptive behaviours in male and female Wistar rats. Food was withdrawn 48 h (short-term food deprivation) prior to performing the formalin test، but water continued to be available ad libitum. The formalin (50 μL، 2%) was injected into hind plantar paw. Immediately after the formalin injection، pain behaviors recorded for 90 minutes. There is significant difference between male and female control Sprague-Dawley rats during phase 2B. Although interphase in male rats is more than female ones، but the phase 2B in female rats is more than male ones and phase 2 finished with delay in Sprague-Dawley race. There are no significant differences between male and female control Wistar rats during formalin test. Following 48-h food deprivation، male and female rats exhibited enhanced nociceptive behaviors in response to formalin injection during phase 1، the interphase، phase 2. In contrast، 48 h food deprivation had significant effect on formalin-evoked nociceptive behaviors in phase 2B for male Wistar and in interphase and phase 2B for female rats. The present study demonstrates the existence of gender and strain-related differences in rats in the development and maintenance of inflammatory hyperalgesia. Also، these differences observed following food deprivation.

It is well-recognized that endogenous opioidergic system plays an important role in pain sensitivity, pain perception, and response to some stressing situations. The present study examined the probable role of endogenous opioidergic system in effects of food deprivation on formalin-induced nociceptive behaviors in male and female rats. To make short-term food deprivation, the rats did not receive food for 48 hours prior to the formalin test. However, they could freely access water. Afterward, 50 µl formalin 2% was injected into the bottom of the rats’ right paw. Naloxone was injected to evaluate the involvement of the endogenous opioidergic system in effects of food deprivation on formalin-induced nociceptive behaviors. Formalin injection caused nociceptive behaviors in two phases. The first and second phases were separated by a brief interphase where nociceptive behaviors decreased. As a result of 48-hour food deprivation, nociceptive behaviors in male and female rats were increased and the second phase was finished with delay. Naloxone administration blocked the pronociceptive effect of the 48-hour food deprivation in the interphase of male rats and in the first phase of female rats. The present study indicated that food deprivation increased formalin-induced nociceptive behaviors through affecting the opioidergic system.

The goals of the study are evaluation the effect (s) of food deprivation as a social stress on testis structure. We also investigated the effects of melatonin treatment as an antioxidant component and inequality on the effect (s) of food deprivation. We investigated the improving effects of melatonin and social stress (food deprivation) on 42 male rats in 7 groups including control، sham، melatonin received (M)، food deprivation (1/3 of control daily food) plus observation (FD)، FD + melatonin (FDM)، isolated FD (FDi)، and FDi + melatonin (FDMi) groups. After 14 days، rats'' testes were studied using immuno histochemistry and TUNEL assays to determine the number of apoptotic cells. Biochemical evaluation was taken on malodialdehide (MDA) and glutathione (GSH). ANOVA and Tukey''s tests were done to analyse the data. The results of sham group was declined for similarity to results of control group. In FD group، MDA was increased significantly Food deprivation can induce oxidative stress which is associated with increasment of apoptotic cells in testis. Isolation can compensate these effects. These results refer to inequality. Since melatonin is recognized for its anti-oxidative and improving effects، we have shown involvement of oxidative stress mechanisms on the stress of food deprivation with inequality.

Orexin-A and orexin-B are novel hypothalamic peptides which have a role in the regulation of feeding behaviour and pain modulation. The purpose of this study was to investigate the role of Orexin-A receptor antagonist (SB334867) on the analgesia produced by 12-14 h of food deprivation in rats. This experimental study was performed on 32 Male rats weighing 2 20 -300gr in Qazvin University of Medical Science in 2010. Animals underwent stereotaxic surgery and a guide cannula was inserted into the lateral ventricle of their brai n. One week after surgery، food was withdrawn 12-14 h prior to performing the formalin test، but water continued to be available ad labium. Formalin was injected subcutaneously into the dorsal surface of the right hindpaw and their pain behaviors observed and recorded for 90 minutes. SB334867 or vehicle (5 μ l، icv) were injected 5 min before formalin injection. Data were analyzed by T-test and one way ANOVA. Formalin injection into the right foot caused pain responses in two phases; first phase and second phase were separated with an interphase in which pain behavior was decreased to single and transient responses. 12-14 h starvation reduced pain behavior (analgesia) but Orexin antagonist injection prevent from the reduction of pain behaviors caused by acute food deprivation. The results of this study suggest that the orexinergic system has a role in the modulation of the pain following food deprivation.

Neuropeptide Y (NPY) neurons express growth hormone secretagogues receptor (GHSR-Ia). Fasting or ghrelin increases food intake by stimulating NPY gene expression via GHSR-Ia. D-Lys3 -GHRP-6، a ghrelin receptor antagonist، decreases food intakes and body weight. The present study aimed to investigate the molecular mechanism of the anorexigenic effect of D-Lys3 -GHRP-6 in food deprived rats. Fifteen food deprived rats (3 groups) received central injections of saline or D-Lys3 -GHRP-6 (2 or 20nmol) respectively and mean food intake was measured at one hour after injections. Mean plasma ghrelin concentration was measured by RIA، and NPY gene expression was determined by semi quantitative RT-PCR in the hypothalamus. Fifteen rats in three groups، received central injection of saline or initiations and on the D-Lys3 -GHRP-6 (2 or 20nmol) twice daily for 9 days respectively. Body weight was determined at third، 7th and 10th day of the experiment. Mean plasma ghrelin concentration، mean food intake and NPY gene expression significantly increased in food deprived rats compared to fed animals. D-Lys3 –GHRP-6 (2 nmol) did not significantly change ghrelin، food intake and NPY mRNA levels، compared to the food deprived rats. However D-Lys3 –GHRP-6 (20 nmol) significantly decreased ghrelin، food intake and NPY mRNA level compared to food deprived group. Results showed that D-Lys3 -GHRP-6 may exert its anorexigenic effect on food intake by influencing the expression of peptides involved in the regulation of energy homeostasis، and may be suggested for the treatment of obesity.

Based on both animal and human studies, inequality and social injustice have adverse effects on individual and community health. However, it is not yet known whether social instability and food inequality can cause the premature aging hepatocytes death in young people. To address this question, the effects of food intake inequality with or without unstable social status were evaluated and histopathological changes in hepatocytes and aging process investigated as well. Forty eight Newzeland white male rabbits were divided into six groups and different social situations were applied to some groups during eight weeks. After the end of the period of the experiment, lipofuscin accumulation and apoptosis as two main markers of aging were studied by long Zeihl Nelseen staining and the terminal deoxynucleotidyl transferase dUTP nike end labeling (TUNEL reaction) of the hepatocytes respectively. Serum cortisol level was also measured. The simultaneous application of the mentioned situations (i.e. food restriction, social inequality and changed cage-mate), caused significant change in lipofuscin accumulation in the hepatocytes in comparison with the control group (p<0.001). In addition, application of instability and isolation environment produced significant changes in hepatocytes apoptosis (p<0.05). Accumulation of two main markers of aging increased in hepatocytes and was accelerated in the groups with unstable social status

Children with types I and II diabetes have to follow a strict diet for an indefinite period of time. In addition, they are also susceptible to stable cognitive impairments including decreased in information processing speed due to the variations in blood sugar levels. The main propose of this study was to compare children with types I and II diabetes in visual and auditory information processing speed related to food stimulies. Forty-three children with diabetes between 6 to 15 years of age admitted to the diabetes center of Firozghar Hospital participated in this study. They were selected through available sampling. Visual and auditory stimuli were presented for the assessment of information processing speed related to food and neutral stimuli. SPSS v.14 was applied to data analysis. ANOVA was used for the comparison between the two groups. Findings showed that children with type I diabetes, in comparison to type II diabetes experienced more damage in the speed of visual and auditory information processing. Both participants with diabetes type I and II processed images and sounds related to food more quickly than nonfood stimuli. Food processing speed increased in stimuli related to food when children with type II diabetes experienced more perceived stress. Base on findings of this article using strategies for self-regulation to avoid highsugar foods have been very difficult; because attention to food stimuli in children increases, self-regulation programs are not easy to implement. Therefore, it is necessary to apply new behavioral therapy to control diabetes in children.

Based on both laboratory animal and human society studies, inequality in food intake and social instability has adverse effects on individuals and community health. However, it is not known whether social instability, food deprivation and food inequality affect neuronal death and premature aging in young animals. To address this question, the effect of food deprivation, food intake inequality with or without unstable social status was evaluated and histopathological changes in hippocampal pyramidal cells and aging process were investigated. Forty eight Newzealand white male rabbits were divided into six groups and different social situations were applied to some groups during eight weeks. After the end of the period of the experiment, lipofuscin accumulation and apoptosis as main markers of aging were studied by long Ziehl Nelseen staining and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay in the hippocampal pyramidal cells, respectively. Serum cortisol level was also measured. The simultaneous application of the mentioned situations (i.e. food deprivation, social inequality and instability) caused a significant change in lipofuscin accumulation in the hippocampal pyramidal cells in comparison with the control group (p<0.005). The results also showed a significant increase in ratio of apoptotic to normal cells in all of the stressed groups compared with control (p<0.05). These findings suggest that food deprivation, inequality in food intake and social instability can enhance the apoptosis rate of hippocampal pyramidal cells through increasing lipofuscin accumulation. Keywords: