• Biomolecules & Therapeutics
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• v.6 no.4
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• pp.337-344
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• 1998

The objective of the present study was to investigate the effect of senescence on the binding properties of muscarinic receptors in the neostriatum of young (3 months), middle-aged (18 months) and aged (33 months) male Fischer 344 x Brown Norway hybrid rats by employing direct binding of selective radiolabeled antagonists. Using the selective M, muscarinic receptor antagonist, $[^3H]$AF-DX384, as the ligand, no significant difference in the maximal receptor density (Bmax) was observed in the neostriatum among any age-groups. In contrast, with the selective M, receptor antagonist, $[^3H]$4-DAMP, a significant increase in the number of muscarinic receptors was observed in neostriatal membrane fractions prepared from the aged animals relative to that observed in the young rats. For each ligand there was no age-related change in its affinity (Kd) for the muscarinic receptors. These results indicate that the observed age-related changes in the muscarinic receptor density may not be necessarily decremuntal and depend upon the muscarinic receptor subtype examined.

• Korean Journal of Exercise Nutrition
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• v.15 no.4
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• pp.183-189
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• 2011

Caffeine and capsaicin increase resting energy metabolism. However, most measurements have been conducted in short-term studies. Therefore, we investigated the effects of caffeine and capsaicin on energy expenditure and energy substrate utilization in resting rats for 6 h. The caffeine (Experiment 1) experiment included four male rats aged 5 weeks and measured the effects of oral administration of caffeine (10 or 50 mg/kg) on respiratory gas, energy expenditure, and energy substrate oxidation for 6 h. Experiment 2 included four male rats aged 6 weeks to measure the effects of capsaicin (10 mg/kg) using the same method as in Experiment 1. The results of Experiment 1 indicated that O₂ uptake and carbohydrate oxidation after caffeine administration for 2 h was higher in the 10 mg trial than that in the 50 mg or placebo trials (P < 0.05). However fat oxidation was not significantly different. In contrast, capsaicin (Experiment 2) observed no differences between the placebo and the capsaicin trials. In conclusion, caffeine initially increased the resting energy consumption for 2 h, and this energy expenditure was due to carbohydrate oxidation. Capsaicin did not change oxygen uptake, respiratory exchange ratio, fat oxidation, or carbohydrate oxidation.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.83-94
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• 1998

Objectives : Phencyclidine(PCP) or PCP-like substances such as ketamine have been known to rekindle the cognitive dysfunction in schizophrenia. The aims of this study were to identify whether PCP-like substances can produce cognitive deficit in schizophrenia, to discuss relation with aging process, and finally to speculate underlying neurochemical mecha-nisms by various drug responses. Methods : In experiment I, radial maze tests were done in 24 Sprague-Dawley rats for 3 days to get baseline data. Being divided into 4 groups(6 rats respectively) of normal aged, normal adult controls, atropine-treated and ketamine-treated, the radial maze tests were repeated on every week for 6 weeks, and then the rats were sacrificed by intracardiac perfusion with phosphate-buffered 10% formaldehyde solution for histology. The brain specimen was stained with hematoxylin-eosin to count cells in the prefrontal cortex and hippocampus. In experiment II, radial maze tests were done for 48 rats before any drug treatment and only after ketamine administration. Thereafter, haloperidol, bromocriptine, clonidine, nimodipine, tacrine, valproic acid, naloxone and fluoxetine were intramuscularly injected on every other day in addition to ketamine. Radial maze tests were repeated on every week for 6 weeks, and then rats were prepared by the same procedure for histology. Results : 1) Reaction times of radial maze tests of atropine-treated rats were significantly prolonged than those of normal aged(p<0.05) or normal adult controls(p<0.05). Cell numbers of prefrontal cortex & hippocampus in ketamine-treated rats were significantly reduced than those in normal aged (p<0.05) or normal adult controls(p<0.005). 2) Reduced cell numbers by ketamine became significantly raised by tacrine administration in prefrontal cortex & hippocampus(p<0.05), while there were no significant changes on radial maze tests. Cell numbers also tended to be raised by nimodipine, fluoxetine and haloperidol administration. Conclusions : In conclusion, the visuospatial memory disorders in ketamine-induced psychotic rats might be partly asso-ciated with aging process. Furthermore, the responses to the various drugs suggested cholinergic system might have an important role in the neurochemical mechanism of the cognitive dysfunction in ketamine-induced psychosis. Otherwise, calcium metabolism as well as serotonergic and dopaminergic systems seemed to be possibly related.

• The Journal of Internal Korean Medicine
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• v.26 no.3
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• pp.533-542
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• 2005

Objectives : In this study, aged BCAO rats were used to observe the effect of Bupleuri Radix on brain ischemic injury because aging is an important factor in storke. Methods : The brain ischemic injury was induced by temporary closing carotids on both sides in a low blood pressure state, and Bupleuri Radix was orally administered to 18 month-old BCAO rats. The ischemic damaged hippocampus and c-Fos and c-Jun expression were analyzed by the immunohistochemical staining. Result and Conclusions : Results are summarized as fellows; 1. The c-Fos expression after inducing a brain ischemic injury in the hippocampus was more inhibited in the experimental group than in the control group. 2. The normalized optical density of c-Fos expression was more reduced in cornu ammonis(CA)1, dentate gyrus(DG) areas in the experimental group than in the control group. 3. The c-Jun expression after inducing a brain ischemic injury in the hippocampus was more inhibited in the experimental group than in the control group. 4. The normalized optical density of c-Jun expression was more reduced in CA1 and DG areas in the experimental group than in the control group.

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.934-942
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• 1996

This study was performed to investigate the influence of dietary fibers on the serum lipid level and bowel function in aged rats. Fiber sources of experimental diets were made from mugwort(M), butterbur(B), apple(A), sea mustard(S) by drying and milling. Each of fiber sources was mixed into the diet at the level of 5, 15% of diet. Sprague-Dawley strain, 13 month old male rats were divided into 9 groups by randomized complete block design : C, M5, B5, A5, S5, M15, B15, A15, S15. The animals were fed ad libitum each of experimental diets for 4 weeks. Control group showed lower food intake compare to the other groups. There were no significant difference between 5% groups and 15% groups in food intake. Fecal weight, dry fecal weight and fecal water content of control group were significantly lower than those of experimental groups, and fecal water content was increased by increasing level of dietary fibber. Apple group showed the lowest values, sea mustard group showed the highest. The shorter transit time was observed in the group of higher intake of dietary fiber. At the same level of dietary fiber, transit time of sea mustard group was shorter than the other groups. With increasing age, serum triglycerides, total cholesterol were increased and HDL-cholesterol was decreased. Fiber fed groups showed lower serum TG, TC and higher HDL-c level compare to the control group. Absorption rates of calcium, magnesium and phosphorus was tend to be lower in the group fed dietary fiber sources than control group. Mucosa weight and maltase activity in the small intestine were decreased by increasing age. As intake of dietary fiber increaed, mucosa weight in the small intestine was not different but maltase activity was decreased.

• Journal of Sasang Constitutional Medicine
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• v.24 no.4
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• pp.62-74
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• 2012

Objectives : The purpose of this study is to investigate the effect of oral administration of Yongyukjowi-tang(YJT) on the immune activity in aged Sprague-Dawley rat(SD rat). Methods : SD rats were divided into three groups: Yongyukjowi-tang groups(YJT groups), distilled water groups(control groups) and Vitamin C groups(positive control groups) which were administered an oral dose(1ml/1day) to 6, 48 and 68 weeks old SD rats for four weeks. After four weeks, the number of total leukocyte, CD3+, CD4+, CD8+, and the level of cytokine (IL-2, IL-4, IL-10, IFN-${\gamma}$) were measured in spleen tissue of each SD rats. Results and Conclusions : 1) The number of total leukocyte significantly increased in 52 weeks old YJT group and 72 weeks old YJT group in comparison with those of the control group. 2) The number of CD3+ cell significantly increased in 72 weeks old YJT group in comparison with those of the control group and the positive control group. 3) The number of CD8+ cell significantly increased in 52 weeks old YJT group in comparison with those of the control group. 4) The level of IL-2 significantly increased in 72 weeks old YJT group in comparison with those of the control group and the positive control group. 5) The level of IL-4 significantly increased in 52 weeks old YJT group in comparison with those of the positive control group. These results suggest that oral administration of YJT has an effect on increase of immune activity in aged rat.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.283-287
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• 2006

Although estrogen is known to playa role in fatty acid metabolism, it remains unclear whether fatty acid oxidation in mature female rats differs from fatty acid oxidation in peri-pubertal young rats. In this study, we measured fatty acid metabolism in the skeletal muscles and livers of 5 and 50 weeks old male and female rats. The rate of palmitate oxidation in the liver and gastrocnemius red in the 50-week-old female rats were elevated as compared to the 5-week-old females, whereas there were no differences in the male rats. The rate of palmitate oxidation in the gastrocnemius red was correlated inversely with intra-abdominal fat mass in the 5-week-old male and female rats, whereas the palmitate oxidation rate was positively correlated with fat mass in the liver and gastrocnemius red in the 50-week-old rats. HOMA-IR and plasma insulin levels were positively correlated with intra-abdominal fat mass in the pooled 50-week-old male and female rats, but this correlation was not apparent in 5-week-old rats. In summary, the rate of fatty acid oxidation measured in the middle-aged adult female rats was significantly higher than those measured in the peri-pubertal young female rats. This difference may be attributed to the influence of ovarian hormones.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.721-730
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• 2005

Recently, epidemiological evidence has raised concerns that moderate elevation in body iron stores may increase oxidative stress and the risk of cardiovascular disease and cancer. Onion flesh or peel contains antioxidant such as flavonoids and alk(en)ylcysteine sulphoxides. This study was conducted to examine the effect of onion flesh or peel feeding on antioxidative capacity in aged rats supplemented with high dietary iron. Thirty-two Sprague-Dawley male 16-month-old rats weighing $618{\pm}6g$ were acclimated for 10 days with medium-iron diet (35ppm in diet), and blocked into 4 groups according to their body weights and raised for 3 months on either control diets (adequate iron-35ppm or high iron-350ppm) or experimental diets containing onion flesh/peel (5% w/w in diet) with high iron (350ppm). Rats fed high iron-onion peel diet had significantly high quercetin and isorhamnetin levels in plasma whereas rats fed high iron-onion flesh diet did not show. Plasma TBARS level was lowered by onion flesh or peel diet with high iron supplementation. However, there was no significant difference in cellular DNA damage in brain and kidney tissue among all experimental groups. We concluded that high iron diet (10 times higher than requirement) tend to increase oxidative stress and it is plausible that onion flesh or peel feeding enhances antioxidative capacity in the elderly even with iron supplementation.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.138-143
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• 2008

We investigated if Chlorella vulgaris (CV) has protective effects on cadmium (Cd) induced liver damage in male Sprague-Dawley (SD) rats. Forty rats, aged 5 weeks old and weighed 90-110g, were divided into a control (with Cd free water), 50 ppm of $CdCl_2$ in drinking water treated groups (Chlorella 0% diet group (Cd/CV0%), Chlorella 5% diet group (Cd/CV5%) or Chlorella 10% diet group (Cd/CV10%). All the rats had freely access to water and diet for 8 weeks. The results show that body weight gain and relative liver weight had significantly lower in Cd/CV0%-treated group than in Cd/CV-treated groups. Hepatic Cd contents showed significantly less by feeding CV (P<0.05). Cd/CV0%-treated rats had significantly (P<0.05) higher hepatic T-MTs, and Cd-MTs concentrations, compared to Cd/CV5% or Cd/CV10% treated rats. The MT I/II mRNA was expressed in the liver of all experimental rats. Its expression was more increased in Cd/CV5%- or Cd/CV10%-treated rats, compared to control and Cd-treated rats. Thus, this study suggested that CV would have a protective effect on Cd-treated liver injury by the reduction of Cd concentrations and stimulation of Cd-MT binds in the liver. However, more studies are needed to identify the proper mechanism of CV and liver toxicity.

• Journal of Ginseng Research
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• v.35 no.3
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• pp.272-282
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• 2011

Ginseng (Panax ginseng Meyer) has been shown to have anti-aging effects in animal and clinical studies. However, the molecular mechanisms by which ginseng exerts these effects remain unknown. Here, the anti-aging effect of Korean red ginseng (KRG) in rat testes was examined by system biology analysis. KRG water extract prepared in feed pellets was administered orally into 12 month old rats for 4 months, and gene expression in testes was determined by microarray analysis. Microarray analysis identified 33 genes that significantly changed. Compared to the 2 month old young rats, 13 genes (Rps9, Cyp11a1, RT1-A2, LOC365778, Sv2b, RGD1565959, RGD1304748, etc.) were up-regulated and 20 genes (RT1-Db1, Cldn5, Svs5, Degs1, Vdac3, Hbb, LOC684355, Svs5, Tmem97, Orai1, Insl3, LOC497959, etc.) were down-regulated by KRG in the older rats. Ingenuity Pathway Analysis of untreated aged rats versus aged rats treated with KRG showed that the affected most was Cyp11a1, responsible for C21-steroid hormone metabolism, and the top molecular and cellular functions are organ morphology and reproductive system development and function. When genes in young rat were compared with those in the aged rat, sperm capacitation related genes were down-regulated in the old rat. However, when genes in the old rat were compared with those in the old rat treated with KRG, KRG treatment up-regulated C21-steroid hormone metabolism. Taken together, Cyp11a1 expression is decreased in the aged rat, however, it is up-regulated by KRG suggesting that KRG seems enhance testes function via Cyp11a1.