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Effects of Medetomidine on Analgesia and Sedation in Rats (Medetomidine의 투여가 흰쥐의 진통과 진정효과에 미치는 영향)

  • Jang, Hwan-Soo;Lee, Maan-Gee
    • Journal of Veterinary Clinics
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    • v.27 no.6
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    • pp.674-678
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    • 2010
  • The effects of medetomidine on the degree of analgesia and sedation in rats were evaluated. The rats were randomly divided into six groups: saline, 1 mL/kg (group 'Saline'); butorphanol, 2.0 mg/kg; medetomidine, 0.2, 0.4, 0.8 or 1.6 mg/kg (group 'MED0.2', 'MED0.4', 'MED0.8' and 'MED1.6', respectively). The degree of analgesia was measured in the $50^{\circ}C$ hot-water tail-flick latency test, and the degree of sedation was evaluated using the numerical sedation score (NSS) and the righting reflex. All doses of medetomidine, except MED0.2, significantly increased the analgesic effect compared to the Saline group. Variables in the MED0.4 and MED0.8 groups, but not in the MED1.6 group, were significantly increased compared to those in the MED0.2 group. However, analgesia with all doses of medetomidine was not significantly different compared to that with butorphanol. Saline and butorphanol treatments did not induce sedation and loss of righting reflex during the recording period. NSS in the MED0.4, MED0.8 and MED1.6 groups were significantly higher than that in the MED0.2 group. NSS in the MED0.8 and MED1.6 groups were not significantly different from that in the MED0.4 group. The latency to loss of righting reflex in the MED0.8 and MED1.6 groups decreased significantly compared to that in the MED0.2 group. Thus, 0.4 and 0.8 mg/kg of medetomidine provided not only reliable analgesia but also sedation to rats. In conclusion, 0.4 to 0.8 mg/kg medetomidine could be a useful chemical restraint method in rats.

Prevention of calcification in bovine pericardial bioprosthesis -pretreatment with surfactants- (우심낭편의 석회화 방지에 관한 연구 - 계면활성제 전처치 효과 -)

  • 안재호;한재진;박성수
    • Journal of Chest Surgery
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    • v.31 no.6
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    • pp.560-566
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    • 1998
  • Background: Bovine pericardial bioprosthesis treated with glutaraldehyde (GA) is one of the most popular prosthetic materials, but late calcific degeneration after implantation is a problem that remains unsolved. For the purpose of mitigating the calcific degeneration, we added MgCl2 into the 0.625% GA solution to compete with calcium for binding to the free aldehyde from GA and pretreated with the surfactants like sodium dodecyl sulfate (SDS) and Triton X-100 before GA fixation for preventing the phospholipid infiltration into the pericardial tissue, the first step of the calcific degeneration. Material and Method: 40 square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2 6H2O as a control group (group 1). 40 pieces pretreated with 1% SDS were also fixed in the same GA solution (group 2) and other 40 pieces pretreated with 1% Triton X-100 were prepared with the same method (group 3). After 1 month of fixation these were implanted into the belly of 40 Sprague-Dawley subdermally and extracted 1 month, 2 months, 3 months and 6 months after implantation. With atomic absorption spectrophotometry we measured the deposited calcium amount. Result: 1 month after implantation we could not find any differences between the three groups, but by the 2nd month calcium deposition was 0.921$\pm$0.121 mg/g in group 1, 0.481$\pm$0.037 mg/g in group 2 and 1.369$\pm$0.200 mg/g in group 3. By the 3rd month it was 0.786$\pm$0.080 mg/g in group 1, 0.584$\pm$0.054 mg/g in group 2 and 1.139$\pm$0.188 mg/g in group 3, and on the 6th month 1.623$\pm$0.601 mg/g in group 1,0.501$\pm$0.043 mg/g in group 2 and 1.625$\pm$0.382 mg/g in group 3, with statistical significance in group 2(p<0.05). Conclusion: Pretreatment with SDS showed meaningful calcium mitigation effects on subcutaneously implanted bovine pericardium in the rat models but the neutral type surfactant, Triton X-100, had no positive mitigation effect in this experiment.

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The Effects of $\alpha$ -Adrenergic Drugs on the Myocardial Preconditioning in Rats. (교감신경계 약물의 허혈-재관류 후 심기능 회복에 미치는 영향)

  • 장원채;송상윤;오상기;안병희;김상형
    • Journal of Chest Surgery
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    • v.34 no.11
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    • pp.809-822
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    • 2001
  • Background: Ischemic preconditioning(IP) is known to be effective in the protection of myocardial necrosis, arrhythmia, and the restoration of the myocardial function in the ischemia-reperfusion state of the heart. However the exact mechanism is not clearly understood. The purpose of this study was to elucidate the trigger mechanism 7f IP on the restoration of the myocardial function after ischemia-reperfusion. Material and Method: By connecting a Langendorff perfusion apparatus with an isolated heart of a rat, the normal temperature of the heart was maintained. The experiment was conducted in seven groups, which were divided according to the preconditioning stimuli and blockage methods Group I(n=10) was a group without IP, Group II(n=10) a group of three-minute IP, Group III(n=10) a group of PEIP, Group IV(n=10) a group of clonidine IP, Group V(n=10) a group of If after reserpine, Group Vl(n=10) a group of PE & prazosin IP, and Group Vll(n=10) a group of clonidine & yohimbine IP. Hemodynamic parameters of DP, LVEDP, $\pm$dP/dT and the changes of perfusion in the coronary artery were evaluated. Result: Developed pressure and +dP/dT changed per unit time. After 20 minutes of reperfusion, those of Group II and III were 63.1$\pm$3.7%, 64.8$\pm$4.6% and 64.5$\pm$4.6%, 63.8$\pm$4.4%, which improved more significantly than those of Group I(P<0.05), However, there were no significant differences between the Groups V and Vl, and Group I. Conclusion: The Brief ischemic preconditioning and pharmacological preconditioning using $\alpha$-receptor sympatho-mimetics have protecting effects on the restoration of myocardial function after reperfusion. And the protecting effect of preconditioning seems to be related to sympathetic neurotransmitters and to the selective action of the $\alpha$$_1$-adrenergic receptor.

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Mitigation of Calcification in Bovine Pericardial Bioprosthesis after Amino Acids Posttreatment (아미노산 후처치의 이종 심낭보철편 석회화 완화 효과)

  • 안재호
    • Journal of Chest Surgery
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    • v.36 no.3
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    • pp.131-135
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    • 2003
  • Bovine pericardium fixed in glutaraldehyde solution (GA) has been one of the most popular surgical bioprosthesis, however, late calcific degeneration after implantation remains to be solved. To mitigate calcific degeneration, we posttreated the bovine pericardium with amino acids after GA fixation. Material and Method: 40 small pieces of bovine pericardia were fixed in 0.625% GA solution with 4 g/L $MgCl_26H_2O$as a control group (group 1). 40 pieces fixed in the same GA solution were posttreated with 2% chitosan solution (group 2) and the other 40 pieces posttreated with 8% glutamate (group 3). These were implanted into the belly of forty Fisher 344 rats subdermally and extracted at f month, 2 months, 3 months and 4 months after implantation. Result: With atomic absorption spectrophotometry we measured the deposited calcium amount and the results were as follows; 2.01 $\pm$0.13 mg/g in group 1, 2.34$\pm$0.73 mg/g in group 2, 2.49$\pm$0.15 mg/g in group 3 at 1 month after implantation, and 3.57$\pm$0.15 mg/g in group 1, 3.52$\pm$0.92 mg/g in group 2, 3.46$\pm$0.12 mg/g in group 3 at the second month. But 5.45$\pm$0.42 mg/g in group 1, 3.22 $\pm$1.31 mg/g in group 2 and 4.20$\pm$0.55 mg/g in group 3 at the 3rd month, which have statistical significance in group 2 (p<0.05). Finally at 4th month, 6.01$\pm$1.21 mg/g in group 1, 3.78$\pm$1.82 mg/g in group 2, 3.92$\pm$0.92 mg/g in group 3, which also have statistical significance (p < 0.05). Conclusion: This means posttreatment with 2% chitosan shows meaningful calcium mitigation effects after 3rd month on subcutaneously implanted bovine pericardium in the rat models but 8% glutamate shows mitigation effect after 4months in this experiment.

Effect of the Various Recovery Diets on the Body Composition of Protein-depleted Rat (각종 회복식이가 무단백식이를 섭취한 흰쥐의 체구성 성분에 미치는 영향)

  • Choi, Young-Ran;Suh, Dong-Hee;Kim, Mi-Kyung;Kim, Sook-He
    • Journal of Nutrition and Health
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    • v.10 no.1
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    • pp.1-9
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    • 1977
  • The changes of the total body composition, internal organs, skeletal muscles, and epididymal fat pad in rats fed protein depletion diet and 4 different recovery diets were examined. Seventy-eight male Sprague-Dawley rats weighing $212{\pm}2$ gr were used, and the results were as follows : A) After the 2 weeks of protein depletion, body weight decreased about 20% from the initial weight. It was mainey due to the total body lipid reduction. Among various organ weights, liver and spleen reduced $35{\sim}58%$, kidney and heart reduced $18{\sim}30%$, and muscles reduced $2{\sim}13%$, while brain, epididymal fat pad were not changed significantly. In regarding protein and lipid contents of these tissues, protein in liver, lipid in muscle, and both in spleen were markedly reduced. B) With the 2 weeks of feeding recovery diets, the increases of body weight were different among 4 Groups. High-fat group gained at the highest level (67%), and high-CHO group the lowest (30%). Total body composition (%) cf the standard and high-protein groups recovered to the level of 0 day protein depletion, while protein in the high-fat group and water in the high-CHO group decreased, and fat in these 2 groups increased. Weights of organs and muscles of the high-protein and high-fat groups were similar to the standard group and tllose of the high-CHO group were lower than the standard group. Composition of organs and muscle in the high-protein group was similar to the standard group, while the N contents of the high-fat and high-CHO groups were lower an the lipid content of the high-fat group was higher than the standard group. The weight and lipid content of epididymal fat pad were the highest in the high-fat group.

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The Effect of the IGF-I treated Gingival and Periodontal Ligament Fibroblast on Osteoblasts (IGF-I으로 처리한 치은 및 치주인대 섬유모세포가 골모세포에 미치는 영향)

  • Kim, Mi-Jeong;Yang, Won-Sik
    • The korean journal of orthodontics
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    • v.31 no.6 s.89
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    • pp.589-600
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    • 2001
  • Insulin-like growth factor I (IGF-I) has the local tissue regulating actions. In bone, IGF-I increases the replication of osteoblastic lineage, probably preosteoblasts, and enhances osteoblastic collagen synthesis and matrix composition rates. The purpose of this study was to investigate the local regulatory effect of IGF-I on periodontium totally, both in an autocrine and paracrine manner. To examine the effect of IGF-I directly on osteoblast (OB) of test rats, and indirectlv on OB via periodontal ligament fibroblast (PDLF), and the effect of gingival fibroblast (GF) on OB via cellular paracrine manner for the understanding of humoral action of adjacent tissue, GF and PDLF were obtained from male Sprague-Dawley rats of six to eight weeks of age. OB was obtained iron frontal and parietal calvarial bone of Sprague-Dawley 21day-old-fetus. After each tell was Incubated 24 hours, for collecting conditioned medium, different concentrations of IGF-I (1,10,100 ng/ml,1ml/well) was adding in the GF, PDLF cells, and the supernatant from these cultures was put into the primary OB culture with $1{\times}10^4$cell/ml/well. The experimental group was divided into six groups control OB, IGF-I treated OB, OB culture with conditioned medium from PDLF, OB culture with conditioned medium from IGF-I treated PDLF, OB culture with conditioned medium from GF, OB culture with conditioned medium from IGF-I treated GF. After final IGF-I treatment, OB was Incubated for 24 hours, and alkaline phosphatase activity assay, BMP expression, cell proliferation measurement using MTT assay, total protein measurement, Collagen synthesis assay using western blot, and examination of bone nodule synthesis were done. Alkaline phosphatase expressions were increased in the group of PDLF-IGF-I supernatant treatment. Direct IGF-I treatment with concentrations of 100ng/m1 showed increased viable tell number measured by MTT assay. And IGF-I treatment did not increase total protein amount. The entire experimental group showed BMP2, 4 expression in western blot, and there was no significant difference between control and experimental groups. These results suggested that supernatant from PDLF effects on increasing cellular activities of OB regardless of IGF-I, and at high concentration, IGF-I increases OB tell proliferation.

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Toxicity Assessment and Establishment Acceptable Daily Intake of Penthiopyrad (펜티오피라드(Penthiopyrad)의 독성평가와 일일섭취허용량 설정)

  • Jeong, Mi-Hye;Hong, Soon-Sung;Park, Kyung-Hun;Kim, Chan-Sub;Park, Jae-Eup;Hong, Moo-Ki;Im, Moo-Hyeog;Kim, Young-Bum;Han, Bum-Seok;Han, Jeung-Sul
    • The Korean Journal of Pesticide Science
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    • v.14 no.4
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    • pp.478-489
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    • 2010
  • Penthiopyrad is a fungicide agent in types of pyrazole which is showing the effect of prevention in fungal disease and powdery mildew. In order to register this new pesticide, reports of acute toxicity and chronic toxicity by animal study were examined to set acceptable daily intake to evaluate hazards of consumers. Acute toxicity was low in toxic, and it did not have the effect of acute dermal toxicity, acute eye irritation, or skin sensitization. As the result of the study in chronic toxicity, the common effect of chemical appeared in the liver and thyroid which was proven as a toxic effect. Two-generation reproduction toxicity, genotoxicity, and prenatal development toxicity were not proven. As the result of carcinogenic study, increase of thyiroid follicular adenoma in the rat and the frequency of liver hepatocellar adenoma in mice were also increased. However, it was decided that the threshold value on the effect in chemicals could be controlled through study liver enzyme induction. Therefore, the ADI for penthiopyrad is 0.081 mg/kg/ bw/day, based on the NOAEL of 8.10 mg/kg bw/day of twelve-months dogs study and applying an uncertainty factor of 100.

Effects of Electroacupuncture on Immobilization Stress Responses : A Study on Inhibitory Avoidance Task, Forced Swimming Test, and Stress Hormones (전기침이 결박 스트레스 반응에 미치는 영향 : 억제성 회피 과제, 강제 수영 시험, 스트레스 호르몬 반응 연구)

  • Kwon, So-Yeon;Kim, Min-Soo;Lee, Sang-Kwan;Je, Jun-Tae;Oh, Jae-Gun;Lee, Jong-Deok;Sung, Kang-Keyng
    • The Journal of Internal Korean Medicine
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    • v.32 no.1
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    • pp.100-112
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    • 2011
  • Objectives : This study investigated the effects of electroacupuncture on memory, depression, and plasma stress hormone levels in rats that were under immobilization stress. Materials and Methods : The immobilization-only group was given two hours of immobilization stress for 10 consecutive days. The immobilization and high frequency EA group was given two hours of immobilization stress simultaneously with high frequency (100Hz) electroacupuncture stimulation on the right ST-36 (Zusanli) for 10 consecutive days. We conducted the inhibitory avoidance and forced swimming tests to recognize whether immobilization stress and electroacupuncture have effects on memory and depression. We collected blood samples from the tail of each rat at 30, 60, 90, and 120-minute intervals during the immobilization stress and EA stimulation to measure plasma concentrations of ACTH, corticosterone, melatonin, and norepinephrine induced by immobilization stress and electroacupuncture. Results : There was a significant effect of high frequency on the increase in anamnesis based on the result of the inhibitory avoidance test, but there was no significant effect of decreasing depression based on the result of the forced swim test. Also, there was no significant effect on the response indicated by stress hormones. Conclusions : 1. High frequency electroacupuncture (100Hz) improved anamnesis in immobilization stress states under the inhibitory avoidance task. 2. High frequency electroacupuncture (100Hz) did not reduce depression induced by immobilization stress under the forced swimming test. 3. High frequency electroacupuncture (100Hz) did not decrease stress hormones through blood sampling.

Effect of Aceriphyllum rossii Ethanol Extract on Lipid Metabolism in Rats Fed a High-Fat Diet (돌단풍 에탄올 추출물이 고지방식이를 급여한 흰쥐의 지질대사에 미치는 영향)

  • Park, Yu-Hwa;Kim, Hee-Yeon;Lim, Sang-Hyun;Kim, Kyung-Hee;Park, Dong-Sik;Lee, Jung-Hoon;Park, Chung-Geon;Park, Chung-Berm;Kim, Song-Mun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.10
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    • pp.1411-1416
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    • 2011
  • In this study, we investigated the anti-obesity activity of Aceriphyllum rossii ethanol extract on rat fed a high fat diet. Male SD rats were divided into four groups. Group 1 was the control. Group 2 was fed a high-fat diet. Group 3 was the positive control, fed a high-fat diet supplemented with Garcinia Cambogia extracts. Group 4 was fed a high fat diet supplemented with ethanol extracts of Aceriphyllum rossii (EEAR). Precisely 166 mg/kg of powdered Garcinia Cambogia extracts was used for Group 3. Also, 250 mg/kg of EEAR was used for Group 4. The Body weight increased Group 2, but decreased Group 4. The serum total cholesterol in Group 2 increased by 15.26% when compared to Group 1, but only increased 5.29% in Group 3 and 4.29% in Group 4. The liver and mesenteric adipose tissue weights of Group 2 increased compared to Group 1, whereas they decreased in Group 3 and Group 4. As a result of measuring the concentration of triglycerides in extracted livers, Group 2 showed a significant increase compared to the Group 1, and Groups 3 and 4 showed significant decrease compared Group 2. These results suggest that Aceriphyllum rossii ethanol extracts may be useful as an anti-obesity agent.

Anti-depressant and anti-anxiety effects of Saccharomyces cerevisiae extract and its hydrolyzed fraction (효모 추출물 SCE 및 그 분획 SCE-40의 항 우울 및 항 불안 효과)

  • Jung, Eun-Yee;Jeong, Min-Suk;Kwon, Young-Bae;Choi, Yoon-Suk;Pyun, Kwang-Ho;Kim, Ki-Won;Shim, In-Sop
    • Science of Emotion and Sensibility
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    • v.10 no.2
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    • pp.243-252
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    • 2007
  • Anti-depressant and anti-anxiety effects of Saccharomyces cerevisiae extract and its hydrolyzed fraction. The purpose of the present study was to examine the effect of Saccharomyces cerevisiae extract (SCE) and its hydrolyzed fraction (SCE-40) on depression and anxiety-related behaviors in mice. Actions of SCE and SCE-40 on serotonin, norepinephrine and GABAergic systems in the rat cerebral cortex membranes were also examined. SCE and SCE-40 significantly reduced the immobility time in the forced swimming and tail suspension test in mice. Duration time of the open arms in the elevated plus maze test was significantly increased in the SCE and SCE-40-treated groups, compared with the saline-treated control group. SCE and its fraction SCE-40 significantly inhibited serotonin and norepinephrine transporter and GABA receptor binding, compared to the saline-treated group. In addition, serotonin and norepinephrine reuptake were significantly suppressed by SCE and SCE-40. These results demonstrate that SCE and SCE-40 produce anti-depressant and anti-anxiety effects through enhancing central serotonin, norepinephrine and GABAergic transmissions. These results suggest that SCE and SCE-40 as functional food might prove to be an effective antidepressant and anti-anxiety agent.

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