• Title/Summary/Keyword: rodent

Search Result 301, Processing Time 0.024 seconds

Imbalance in the spinal serotonergic pathway induces aggravation of mechanical allodynia and microglial activation in carrageenan inflammation

  • Junxiu Jin;Dong Ho Kang;Jin Jeon;Hyung Gon Lee;Woong Mo Kim;Myung Ha Yoon;Jeong Il Choi
    • The Korean Journal of Pain
    • /
    • v.36 no.1
    • /
    • pp.51-59
    • /
    • 2023
  • Background: This study investigated the effect of an excess and a deficit of spinal 5-hydroxytryptamine (5-HT) on the mechanical allodynia and neuroglia activation in a rodent pain model of carrageenan inflammation. Methods: Male Sprague-Dawley rats were implanted with an intrathecal (i.t.) catheter to administer the drug. To induce an excess or deficit of 5-HT in the spinal cord, animals were given either three i.t. 5-HT injections at 24-hour intervals or a single i.t. injection of 5,7-dihydroxytryptamine (5,7-DHT) before carrageenan inflammation. Mechanical allodynia was measured using the von Frey test for 0-4 hours (early phase) and 24-28 hours (late phase) after carrageenan injection. The changes in the activation of microglia and astrocyte were examined using immunofluorescence of the dorsal horn of the lumbar spinal cord. Results: Both an excess and a deficit of spinal 5-HT had no or a minimal effect on the intensity of mechanical allodynia during the early phase but prevented the attenuation of mechanical allodynia during the late phase, which was observed in animals not treated with i.t. 5-HT or 5,7-DHT. Animals with an excess or deficit of 5-HT showed stronger activation of microglia, but not astrocyte, during the early and late phases, than did normal animals. Conclusions: Imbalance in the descending 5-HT pathway in the spinal cord could aggravate the mechanical allodynia and enhance the activation of microglia, suggesting that the spinal 5-HT pathway plays an essential role in maintaining the nociceptive processing in balance between facilitation and inhibition in inflammatory pain caused by carrageenan inflammation.

Placental development in the early stages of red-rumped agouti pregnancy (Dasyprocta leporina Linnaeus, 1758)

  • Gleidson Benevides, de Oliveira;Helio Noberto de Araujo Junior;Carlos Eduardo Bezerra de Moura;Phelipe Oliveira Favaron;Alexsandra Fernandes Pereira;Moacir Franco de Oliveira
    • Journal of Veterinary Science
    • /
    • v.24 no.5
    • /
    • pp.49.1-49.15
    • /
    • 2023
  • Background: Hystricomorpha rodents display a similar placentation model to humans. The present study was carried out considering the scarcity of information concerning the placental development in agouti. Objective: Describe the microscopy of the placenta, subplacenta and yolk sac of agoutis in early pregnancy and report on the inversion of the yolk sac. Methods: Fifteen females between the 14th-32nd day of gestation were used following euthanasia. Gestational buttons were collected, fixed, processed, stained to optical microscopy or immunohistochemistry. Results: Chorioallantoic placenta (CP) ranged from conical to a half-sphere, as follows: from the 14th to 17th day, the CP displays an inverted "V" shape, predominantly formed by cytotrophoblasts; from 20 to 22 days, formed almost entirely by cytotrophoblasts; at 28 days, a half sphere, with distinct lobes and interlobular area, numerous maternal gaps delimited by syncytiotrophoblasts and trophoblast giant cells; at 32 days, globose and undergoing the maturation process. Subplacenta, located between decidua and CP, initially presents septa consisting of simple columnar epithelium and after 17 days, comprising stratified epithelium. Visceral yolk sac (VYS) is attached to two CP projections between 14 and 17 days, formed by a simple cubic epithelium and inverted. Between 20 and 22 days, the epithelium displays apical villous projections with cytoplasmic vacuoles and a vascularized mesoderm. After the 24th day, the VYS near the placenta is pleated, very vascularized and villous, with decreased villi sizes further away from the placenta. Conclusion: The agouti CP displays similar characteristics to other hystricomorpha, including placenta lobulation, a subplacenta and an inverted vitelline placenta.

Differential expression of the enzymes regulating myosin light chain phosphorylation are responsible for the slower relaxation of pulmonary artery than mesenteric artery in rats

  • Seung Beom Oh;Suhan Cho;Hyun Jong Kim;Sung Joon Kim
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.28 no.1
    • /
    • pp.49-57
    • /
    • 2024
  • While arterial tone is generally determined by the phosphorylation of Ser19 in myosin light chain (p-MLC2), Thr18/Ser19 diphosphorylation of MLC2 (pp-MLC2) has been suggested to hinder the relaxation of smooth muscle. In a dual-wire myography of rodent pulmonary artery (PA) and mesenteric artery (MA), we noticed significantly slower relaxation in PA than in MA after 80 mM KCl-induced condition (80K-contraction). Thus, we investigated the MLC2 phosphorylation and the expression levels of its regulatory enzymes; soluble guanylate cyclase (sGC), Rho-A dependent kinase (ROCK) and myosin light chain phosphatase target regulatory subunit (MYPT1). Immunoblotting showed higher sGC-α and ROCK2 in PA than MA, while sGC-β and MYPT1 levels were higher in MA than in PA. Interestingly, the level of pp-MLC2 was higher in PA than in MA without stimulation. In the 80K-contraction state, the levels of p-MLC2 and pp-MLC2 were commonly increased. Treatment with the ROCK inhibitor (Y27632, 10 µM) reversed the higher pp-MLC2 in PA. In the myography study, pharmacological inhibition of sGC (ODQ, 10 µM) slowed relaxation during washout, which was more pronounced in PA than in MA. The simultaneous treatment of Y27632 and ODQ reversed the impaired relaxation in PA and MA. Although treatment of PA with Y27632 alone could increase the rate of relaxation, it was still slower than that of MA without Y27632 treatment. Taken together, we suggest that the higher ROCK and lower MYPT in PA would have induced the higher level of MLC2 phosphorylation, which is responsible for the characteristic slow relaxation in PA.

Effects of Goat Milk and Fermented Goat Milk on Reproductive Function and Stamina of the Male Rodent (산양유 및 산양유 발효유가 웅성 설치류의 생식기능과 지구력에 미치는 영향에 관한 연구)

  • Im, Kyung-Soon;Kang, Jae-Ku;Choi, Ki-Myung;Pae, Chang-Joon;Joh, Woo-Jea
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.27 no.4
    • /
    • pp.373-380
    • /
    • 2000
  • Objective: The purpose of this study was to evaluate effects of goat milk and fermented goat milk on reproductive function and stamina of male rodent. Methods: Experiment I: Male ICR mouse was divided into four groups. Group 1 none-treated control; Group 2 received saline; Group 3 received cow milk 10 ml/kg per day for 15 days; Group 4 received goat milk 10 ml/kg per day for 15 days. The cauda epididymal sperm motility and testicular sperm production were investigated. Experiment II: Male SD rat was divided into three groups. Group 1 received saline; Group 2 received goat milk 10 ml/kg per day for 28 days; Group 3 received fermented goat milk 10 ml/kg per day for 28 days. The cauda epididymal sperm motility and testicular sperm production were also investigated. The concentration of testosterone in serum at 1 and 3 weeks after treatment was determined using Immulite 2000 kit. Testes, epididymis, prostate, and seminal vesicle were weighed. Experiment III: Male ICR mouse was divided into four groups. Group 1 none-treated control; Group 2 received saline; Group 3 received goat milk 10 ml/kg per day for 4 weeks; Group 4 received fermented goat milk 10 ml/kg per day for 4 weeks. After treatment, the mouse was forced to swim to test for stamina. Results: In Experiment I, the cauda epididymal sperm motility after in vitro culture for 1 or 3 h was significantly (p<0.05) higher in cow milk and goat milk than in the control and saline. There was no significant difference in the cauda epidymal sperm motility between cow and goat milk. The testicular spermatid number was significantly (p<0.01) higher in goat milk (222.8${\times}10^6$) than in the control (108.6), saline (98.2), and cow milk (118.2). In Experiment II, the cauda epididymal sperm motility after in vitro culture for 1 h was significantly (p<0.05) higher in fermented goat milk than in saline and goat milk. There was no significant difference in the cauda epidymal sperm motility between saline and goat milk but goat milk showed slightly higher sperm motility than saline. After in vitro culture for 3 h, the cauda epididymal sperm motility was significantly (p<0.01) higher in fermented goat milk and goat milk than in saline. The testicular spermatid number was significantly (p<0.05) higher in goat milk than in saline, and significantly (p<0.01) higher in fermented goat milk than in saline. And the serum testosterone levels of rats administered with goat milk or fermented goat milk were increased but were no significant difference among three groups. Also the prostate weight was significantly (p<0.05) increased in the goat and fermented goat milk. In Experiment III, the swimming time in the goat milk and fermented goat milk groups was significantly (p<0.01) longer than in the control and saline. There was no significant difference in the swimming time between goat and fermented goat milk but the fermented goat milk showed slightly longer swimming time than the goat milk. Conclusion: The cauda epididymal sperm motility, the testicular spermatid number and stamina were improved when the mice and rats were drunk with goat milk or fermented goat milk.

  • PDF

Effects of Treadmill Exercise on Alpha-synuclein Mutation and Activated Neurotrophins in Nigrostriatal Region of MPTP-induced Parkinson Models (MPTP 파킨슨 모델의 트레드밀 운동이 알파시누크린 변성과 흑질선조체내 신경성장인자 활성화에 미치는 영향)

  • Park, Jae-Sung;Kim, Jeong-Hwan;Yoon, Sung-Jin
    • Journal of Korean Medicine Rehabilitation
    • /
    • v.19 no.2
    • /
    • pp.73-88
    • /
    • 2009
  • Objectives : Neuronal changes that result from treadmill exercise for patients with Parkinson's disease(PD) have not been well documented, although some clinical and laboratory reports suggest that regular exercise may produce a neuroprotective effect and restore dopaminergic and motor functions. However, it is not clear if the improvements are due to neuronal alterations within the affected nigrostriatal region or result from a more general effect of exercise on affect areas and motivation. In this study, we demonstrate that motorized treadmill exercise improves the neuronal outcomes in rodent models of PD. Methods : We used a chronic mouse model of parkinsonism, which was induced by injecting male C57BL/6 mice with 10 doses(Every 12 hour) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (30 mg/kg) and probenecid (20 mg/kg) over 5 days. These mice were able to sustain an exercise training program on a motorized rodent treadmill at a speed of 18 m/min, $0^{\circ}$ of inclination, 40 min/day, 5 days/week for 4 weeks. At the end of exercise training, we extracted the brain and compared their neuronal and neurochemical changes with the control(saline and sedentary) mice groups. Synphilin protein is the substance that manifestly reacts with ${\alpha}$-synuclein. In this study, we used Synphilin as a manifest sign of recovery from neurodegeneration. We analyze the brain stems of the substantia nigra and striatum region using the western blotting technique. Results : There were no expression of synphilin in the saline-induced groups. The addition of MPTP(1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) greatly accelerated synphilin expression which meant an aggregation of ${\alpha}$-synuclein. But, the MPTP-induced treadmill exercise group showed significantly lower expression than the MPTP-induced sedentary group. This means treadmill exercise has a definite effect on the decrease of ${\alpha}$-synuclein aggregation. Conclusions : In this study, our results suggest that treadmill exercise promoted the removal of the aggregation of ${\alpha}$-synuclein, resulting in protection against disease development and blocks the apoptotic process in the chronic parkinsonian mice brain with severe neurodegeneration.

An Analysis on the Contents of the Environmental Health in the Primary, Middle and High School Textbooks (초 . 중 . 고등학교 교과서의 환경관련 내용분석연구)

  • 남철현;류장근;최연정;황연자
    • Journal of Environmental Health Sciences
    • /
    • v.20 no.4
    • /
    • pp.98-117
    • /
    • 1994
  • To provide data for the contents regarding environmental health (environmental hygiene, environmental pollution) in the textbooks of primary, middle and high schools, a total of 243 textbooks was analysed for two months from May, to July 31, 1993. Among the total 52844.50 pages, 1.65% was related to the environmental health, which account for 870.00 pages. In the textbooks by school level, the rate of the contents regarding environmental health in primary school was 1.63% (148.75 pages). that of middle school was 1.96% (243.25 pages) and that of high school was 1.53% (478.00 pages). The area of environmental hygiene was 0.24% (129.25 pages) and that of environmental pollution was 1.40% (740.75 pages) which is slightly high. In the field of environmental hygiene, the rate of the contents in the middle school textbooks was 0.53% which was the higher than that of the primary and high school textbooks. The rate of environmental pollution area was not significantly different by school level but the number of the pages was the higher at the high school than that of the primary and middle schools, which account for 428.8 pages. The contents related by the areas were as follows: 1. Contents related to environmental hygiene 1) Among environemtnal hygiene contents, the rate of housing sanitation was the highest as 0.14% (73.00 pages), that of air environment was 0.06% (33.00 pages) and that of water supply sanitation was 0.03% (17.25 pages). The portion of air environment was 5.00 pages in the primary school textbooks and that of housing sanitation at the middle and high schools was each 35.0 pages, 35.50 pages, which was the more than that of other fields. By school year, there was no contents related at the 1st and 2nd grades but were 4.75 pages at the 4th grade which were the more than those of other grades. At the 5th grade, water supply sanitation part was found but not air environment. Housing sanitation was found at the 3rd, 5th grades and insect or rodent control was at the 3rd, 4th, 5th, 6th grades. 2) In the middle school textbooks related to environmental health, 41.0 pages were included in the textbooks of pysical education, the highest number. The next was 19.5 pages in home economics, 2.8 pages in social studies and 3.00 pages in others. The contents of air environment were found in the textbooks of physical education and science, those of water supply and housing sanitation were in home economics and physical education and those of insect control were found 0.5 pages in home economics only. 3) In the high school textbooks, the highest number was 27.8 pages of home economics and the next was 11.5 pages of others, 7.8 pages of physical education, 2.0 pages of science and 0.3 pages of social studies. Air environment parts were included in the textbooks of science, physical education and home economics and water sanitation was in home economics, physical education and others. Housing sanitation was showed in home economics and social studies, on the other side the contents of insect or rodent control was found in home economics and physical education. 4) By the subjects related to environmental hygiene in the primary, middle and high school textbooks, 51.0 pages of home economics were the highest portion. It was also revealed that 49.5 pages of physical education, 14.5 pages of others, 13.5 pages of science and 0.8 pages of social studies were included. The number of 33.0 pages of air environment portion was distributed into 9.75 pages of science, 19.0 pages of physical education and 4.25 pages of others. Among 17.3 pages of water sanitation, 3.5 pages of home economics, 11.3 pages of physical education and 2.5 pages of others were included. Housing sanitation portions were 73.0 pages, which were distributed into 46.5 pages of home economics, 0.5 pages of social studies, 18.3 pages of physical education and 7.8 pages of others. 5) The number of photo, figure, illustration and table related in the primary school textbooks was 31. Among them, the number of photos was 21, that of figures or illustrations was 9 and that of table was 1. The number of 63 in the middle school textbooks was classified into 3 photos, 32 figures or illustrations and 28 tables. At the high school, the number of 56 was included 2 photos, 41 figures or illustrations and 13 tables.2. Contents related to environmental pollution 1) In the field of environmental pollution, the rate of water pollution was 0.39% (203.3 pages), that of air pollution was 0.31% (161.5 pages) that of soil pollution was 0.1% (57.3 pages), that of refuse disposal was 0.08% (40.3 pages) and others was 0.5% (278.5 pages) by school level, the rate of water pollution in the primary, middle and high schools was each 40.5, 48.0, 118.8 pages and that of air pollution was each 20.8, 38.3, 102.5 pages. 2) Environmental pollution areas were not inserted in the textbooks at the 1st grade of the primary school but foqnd 5.5 pages at the 2nd grade, 30.5 pages at the 4th grade, 36.3 pages at the 5th grade and a,9.5 pages at the 6th grade. Water pollution was included from the 2nd grade, air pollution and refuse disposal from the 3rd grade and soil pollution from the 5th grade. 3) In the middle school textbooks, environmental pollution was distributed into 90.25 pages of science, 42.8. pages of physical education, 20.5 pages of social studies, 19.5 pages of others and 4.0 pages of home economics. At the high school, the contents were found 191.3 pages in science, 119.3 pages in others, 88.5 pages in social studies, 28.5 pages in physical education and 1.3 pages in home economics. 4) By subjects of the primary, middle and high schools, the portion of environmental pollution was classified into 322.2 pages of science, 195.0 pages of social studies, 138.8 pages of others, 76.3 pages of physical education and 8.5 pages of home economics. Air and soil pollution parts were not found in the subjects of home economics. 5) The number of photo, figure or illustration and table related in the primary school textbooks was 218. Among them, the number of photos was 61, that of figures or illustrations was 149 and that of tables was 8. At the middike school, the number of 153 was distributed into 99 photos, 34 figures or illustrations and 20 tables. The number of 129 found in the high school textbooks was included 129 photos, 73 figures or illustrations and 100 tables.

  • PDF

The Effect of Exercise Training (EXE) on Myocardium Glucose Metabolic Phenotypic Proteins and HSP-60 Protein Expression after Ischemia/Reperfusion Injury in STZ-induced Rats (지구성 운동이 STZ-당뇨 유발 쥐의 허혈/재 관류 손상 후 심근의 당대사 관련 표현형 단백질과 HSP-60 단백질 발현에 미치는 영향)

  • Bae, Hee-Suk;Um, Hyun-Seob;Kang, Eun-Bum;Yang, Chum-Yeol;Lee, Yong-Ro;Lee, Chang-Guk;Cheon, U-Ho;Jeon, Hye-Ja;Cho, In-Ho;Cho, Joon-Yong
    • Journal of Life Science
    • /
    • v.19 no.5
    • /
    • pp.644-651
    • /
    • 2009
  • The objective of this study was to identify EXE (1 hr a day at 21 m/min for 5 day/wk, at 0 % grade for 6 wk) on myocardium glucose metabolic phenotypic proteins (AMPK-PGC-1${\alpha}$-GLUT-4) and HSP-60 protein expression after ischemia/reperfusion injury (IRI) in STZ-induced rats. EXE was performed using STZ-induced diabetic rats on a rodent treadmill (28 m/min, 1 hr/day, 5 day/wk for 6 wk). The results of this study suggest that i) serum insulin level was not changed among groups (p>l0.05). ii) the LVDP level increased significantly in the STZ-EXE-IRI group compared to the STZ-IRI group at 60 min (p<0.01), 70 min (p<0.05) and 80 min (p<0.05) after reperfusion, respectively, and iii) AMPK phosphorylation (p<0.01), PGC-1${\alpha}$ protein (p<0.001), GLUT-4 protein (p<0.001) and HSP-60 protein expressions (p<0.05) increased significantly in the STZ-EXE-IRI group compared to the STZ-IRI group. In conclusion, the findings of the present study reveal that EXE may provide therapeutic value to insulin dependent diabetic patients with peripheral insulin resistance and myocardium injury by improving glucose metabolic proteins (AMPK-PGC-1${\alpha}$-GLUT-4) and heat shock protein-60 (HSP-60), along with increasing LVDP levels and decreasing glucose levels. Therefore, EXE protects the STZ-induced diabetic myocardium injury against ischemia/ reperfusion injury.

Adiponectin induced AMP-activated protein kinase impairment mediates insulin resistance in Bama mini-pig fed high-fat and high-sucrose diet

  • Niu, Miaomiao;Xiang, Lei;Liu, Yaqian;Zhao, Yuqiong;Yuan, Jifang;Dai, Xin;Chen, Hua
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.30 no.8
    • /
    • pp.1190-1197
    • /
    • 2017
  • Objective: Adipose tissue is no longer considered as an inert storage organ for lipid, but instead is thought to play an active role in regulating insulin effects via secretion adipokines. However, conflicting reports have emerged regarding the effects of adipokines. In this study, we investigated the role of adipokines in glucose metabolism and insulin sensitivity in obese Bama mini-pigs. Methods: An obesity model was established in Bama mini-pigs, by feeding with high-fat and high-sucrose diet for 30 weeks. Plasma glucose and blood biochemistry levels were measured, and intravenous glucose tolerance test was performed. Adipokines, including adiponectin, interleukin-6 (IL-6), resistin and tumor necrosis factor alpha ($TNF-{\alpha}$), and glucose-induced insulin secretion were also examined by radioimmunoassay. AMP-activated protein kinase (AMPK) phosphorylation in skeletal muscle, which is a useful insulin resistance marker, was examined by immunoblotting. Additionally, associations of AMPK phosphorylation with plasma adipokines and homeostasis model assessment of insulin resistance (HOMA-IR) index were assessed by Pearce's correlation analysis. Results: Obese pigs showed hyperglycemia, high triglycerides, and insulin resistance. Adiponectin levels were significantly decreased (p<0.05) and IL-6 amounts dramatically increased (p<0.05) in obese pigs both in serum and adipose tissue, corroborating data from obese mice and humans. However, circulating resistin and $TNF-{\alpha}$ showed no difference, while the values of $TNF-{\alpha}$ in adipose tissue were significantly higher in obese pigs, also in agreement with data from obese humans but not rodent models. Moreover, strong associations of skeletal muscle AMPK phosphorylation with plasma adiponectin and HOMA-IR index were obtained. Conclusion: AMPK impairment induced by adiponectin decrease mediates insulin resistance in high-fat and high-sucrose diet induction. In addition, Bama mini-pig has the possibility of a conformable model for human metabolic diseases.

The Carcinogenic Liver Fluke Opisthorchis viverrini is a Reservoir for Species of Helicobacter

  • Deenonpoe, Raksawan;Chomvarin, Chariya;Pairojkul, Chawalit;Chamgramol, Yaowalux;Loukas, Alex;Brindley, Paul J;Sripa, Banchob
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.5
    • /
    • pp.1751-1758
    • /
    • 2015
  • There has been a strong, positive correlation between opisthorchiasis-associated cholangiocarcinoma and infection with Helicobacter. Here a rodent model of human infection with Opisthorchis viverrini was utilized to further investigate relationships of apparent co-infections with O. viverrini and H. pylori. A total of 150 hamsters were assigned to five groups: i) Control hamsters not infected with O. viverrini; ii) O. viverrini-infected hamsters; iii) non-O. viverrini infected hamsters treated with antibiotics (ABx); iv) O. viverrini-infected hamsters treated with ABx; and v) O. viverrini-infected hamsters treated both with ABx and praziquantel (PZQ). Stomach, gallbladder, liver, colonic tissue, colorectal feces and O. viverrini worms were collected and the presence of species of Helicobacter determined by PCR-based approaches. In addition, O. viverrini worms were cultured in vitro with and without ABx for four weeks, after which the presence of Helicobacter spp. was determined. In situ localization of H. pylori and Helicobacter-like species was performed using a combination of histochemistry and immunohistochemistry. The prevalence of H. pylori infection in O. viverrini-infected hamsters was significantly higher than that of O. viverrini-uninfected hamsters ($p{\leq}0.001$). Interestingly, O. viverrini-infected hamsters treated with ABx and PZQ (to remove the flukes) had a significantly lower frequency of H. pylori than either O. viverr-iniinfected hamsters treated only with ABx or O. viverrini-infected hamsters, respectively ($p{\leq}0.001$). Quantitative RT-PCR strongly confirmed the correlation between intensity H. pylori infection and the presence of liver fluke infection. In vitro, H. pylori could be detected in the O. viverrini worms cultured with ABx over four weeks. In situ localization revealed H. pylori and other Helicobacter-like bacteria in worm gut. The findings indicate that the liver fluke O. viverrini in the biliary tree of the hamsters harbors H. pylori and Helicobacter-like bacteria. Accordingly, the association between O. viverrini and H. pylori may be an obligatory mutualism.

Evaluation of the Genetic Toxicity of Synthetic Chemicals (Ⅶ) -A Synthetic Selective Herbicide, Pendimethalin- (합성화학물질들의 유전독성평가(Ⅶ) -합성 제초제인 Pendimethalin-)

  • Ryu, Jae-Chun;Kim, Kyung-Ran
    • Environmental Analysis Health and Toxicology
    • /
    • v.18 no.2
    • /
    • pp.121-129
    • /
    • 2003
  • The genotoxicity of pendimethalin [N-(l-ethylpropyl)-2, 6-dinitro-3, 4-xylidine, C$\_$13/H$\_$19/N$_3$O$_4$, M.W.=281.3, CAS No. 40487-42-1], one of selective herbicide, was evaluated in bacterial gene mutation system, chromosome aberration in mammalian cell system and in vivo micronucleus assay with rodent. In bacterial gene mutation assay, pendimethalin revealed dose-dependent mutagenic potential in 313 ∼ 5,000 ${\mu}$g/plate of Salmonella typhimurium TA 98 and TA 1537 both in the absence and presence of S-9 metabolic activation system, and TA 100 only in the absence of S-9 mixture. In the TA 1535, slight increase of revertant was also observed in the presence of S-9 metabolic activation system. No mutagenic potential was observed in the TA 1535 without metabolic activation system and TA l00 in the presence of S-9 mixture. In mammalian cell system using Chinese hamster lung (CHL) fibroblast, no clastogenicity of pendimethalin was observed both in the absence and presence of S-9 metabolic activation system in the concentration range of 2.32∼9.28 ${\mu}$g/ml. And also, in vivo bone marrow micronucleus assay, pendimethalin revealed no clastogenic potential in the dose range of 203∼810 mg/kg body weight after oral administration in mice. Consequently, in vitro chromosome aberration with mammalian cells and in vivo bone marrow micronucleus assay revealed no clastogenic potential of pendimethalin. However, pendimethalin revealed mutagenic potential in bacterial gene mutation assay.