Although bombesin (BN) regulates colonic motility, the associated mechanism of action remains unclear. The objective of this study was to investigate the effect of BN on colonic motility using isolated rat colon. An isolated rat colon was perfused with Krebs solution via the superior mesenteric artery. Intraluminal pressure was measured via microtip catheter pressure transducers at both proximal and distal portions of the isolated colon. After a control period, BN was administered intraarterially in concentrations of 13, 26, 130, and 260 pM. After pretreatment with hexamethonium (10-3 M), atropine (10-5 M), or tetrodotoxin (10-6 M), BN was administered at a concentration of 260 pM (proximal colon) or 130 pM (distal colon); intraluminal pressure was then monitored. Changes in motility were expressed as the percentage change of motility index (MI) over the basal period. As a result, BN increased colonic motility and a dose-dependent increase in proximal colonic motility was observed. The stimulant effect of BN was almost completely abolished by atropine and tetrodotoxin at both the proximal and distal colon. However, BN was not inhibited by hexamethonium at both the proximal and distal colon. Therefore, the stimulant action of BN may be mediated by local cholinergic muscarinic receptors.

Diagnosis with an ex-vivo gold sensor was done using a modified fluorine-doping sensor, and cyclic voltammetry (CV) redox potentials of 0.4 V anodic and -0.2 V cathodic were obtained. Both peak currents were optimized using square-wave (SW) stripping voltammetry, and an analytical working range of 10-80 ug/L SW was attained. The precision of the 10-mg/L Au was 0.765 (n=8) RSD under the optimum conditions, and the analytical detection limit approached 0.006 ug/L (S/N=3) with only a 60 sec accumulation time. The developed method was used to examine the mouse droppings for medicinal diagnosis.

본 연구는 가축 체지방 감소를 위한 수동면역학적 기법의 기초자료 확보를 위해 흰쥐 지방부위별(복강 및 피하지방) 특이 다클론 항체를 개발하고자 실시되었다. 흰쥐 부위별 지방 조직에서 지방세포를 분리하고 각각 primary 배양시킨 후 개발된 복강지방(AAb) 및 피하지방 특이 다클론 항체(SAb)를 주입한 뒤 media 내 lactate dehydrogenase(LDH) 방출 수준을 조사하였다. 희석배율 1:1,000배를 기준으로 비면역혈청은 항원-항체 결합 반응이 거의 측정되지 않았고, AAb 및 SAb는 희석배율 1:128,000배까지 각각 항원-항체 반응이 감지되었다. 부위별 지방과 비교했을 때, AAb 및 SAb는 흰쥐 타 장기들과는 특이한 반응을 나타내지 않았다(p<0.001). 본 연구에서 개발한 두 항체들은 모두 항원으로 이용된 부위의 지방세포 PMP와 가장 높은 반응을 나타내었으며, 지방세포 배양을 통한 LDH 수준 검사에서는 AAb 및 SAb 모두 비면역혈청에 비해 유의적으로 높은 세포파괴가 일어났음을 확인할 수 있었다(p<0.01). 이상의 결과를 종합할 때 본 연구에서 개발된 AAb 및 SAb는 높은 역가, 타장기 안전성 및 in vitro 지방 감소 효과가 있었다고 생각된다.

SD-rat에 대조구(Control), 고 콜레스테롤(HC), 3.5% 펙틴-가수분해 효소(Viscozyme L)로 처리된 토마토 케이크(ETC) 를 각각 4주 간 급이하였다. 첫 일주일에는 HC-급이군의 체증 증가가 151.7%로 유의적 증가를 보였지만(p<0.05), ETC- 급이군의 경우는 115.4%를 보였다. Control- 및 ETC-급이군의 사료 효율은 각각 0.236±0.041 및 0.447±0.030으로 HC-급 이군의 경우(0.355±0.034)에 비하여 유의적인 차이를 보였다(p<0.05). ETC-급이군의 신장 및 부고환의 지방체는 각각 0.303 및 0.274 g 씩 감소하였다. HC-와 ETC-급이군 간의 혈청 콜레스테롤, 트리글리세라이드, HDL- 및 LDL-콜레스테 롤 수치의 유의적인 차이는 보이지 않았다. ETC-급이군의 경우 2주 급이시 ABTS radicals로 평가한 총 항산화 활성은 약 1.1배 높았으며, 2 및 4주간 급이시 glutathione peroxidase 활성은 각각 2.5 및 1.3배 높게 나타났다.

The purpose of the present study was to investigate the effects of familiar exercise and novel exercise on motor function after intracerebral hemorrhage (ICH) in rats. The rats were subjected to a unilateral striatal ICH via collagenase infusion. The rats were randomly divided into the following three groups: the CON (control group; rested one week post-ICH), the FE (familiar exercise group; familiar exercise was performed two weeks after one-week post-ICH period), and NE (novel exercise group; novel exercise was performed two weeks after one-week post-ICH period). We measured neurological behavior using a ladder rung walking test and a beam walking test; we measured the level of nerve growth factor (NGF) using immunohistochemistry and western blot analysis. We performed a one-way ANOVA test to analyze the scores obtained from the neurological behavior tests and the differences of NGF protein levels among the three groups. In the present study, the FE group and the NE group showed significant improvement during the neurological behavior tests and in their expression of NGF protein level, as compared to the CON group. Especially, NE group more increase than FE group in neurological behavior tests, the expression of NGF on motor cortex. In conclusion, these results suggest that, after ICH, familiar exercise and novel exercise enhance motor function and, novel exercise is more effective than familiar exercise.

Linuron is a pesticide with a weak anti-androgenic property, which impacts male reproductive organs. In this study, to clarify whether linuron affects the cellular antioxidant system of ventral prostate, gene expression patterns of the representative antioxidant enzymes such as glutathione peroxidase (GPx), selenoprotein P (SePP), and superoxide dismutase (SOD) were investigated in the rat ventral prostates exposed to linuron using real-time RT-PCR analyses. Sprague-Dawley rats castrated at 6 weeks old were treated with linuron (25, 50, or 100 mg/kg per oral) daily for 10 days after testosterone propionate administration (0.4 mg/kg) subcutaneously. As compared to normal control animals, mRNA levels of phospholipid hydroperoxide GPx (PHGPx), SePP, and Mn SOD significantly increased in the prostates exposed to linuron (25, 50, and 100 mg/kg). However, cytosolic GPx (100 mg/kg) and Cu/Zn SOD (25, 50, and 100 mg/kg) mRNA levels significantly decreased in the ventral prostates. These results indicate that linuron upregulates the expressions of PHGPx, SePP, and Mn SOD mRNAs, but down-regulates the expressions of cytosolic GPx and Cu/Zn SOD in rat prostates, suggesting that linuron may have dual effects in the cellular antioxidant system of prostate.

Tooth development involves bud, cap, bell and hard tissue formation stages, each of which is tightly controlled by regulatory molecules. The aim of this study was to identify genes that are differentially expressed during dental hard tissue differentiation. Sprague-Dawley rats at postnatal days 3, 6 and 9 were used in the analysis. Differential display RT-PCR (DD-PCR) was used to screen differentially expressed genes between the 2nd (root formation stage, during mineralization) and 3rd (cap stage, before minerali-zation) molar germs at postnatal day 9. The DNA detected in the 2nd molar germs showed homology to osteonectin only (GenBank accession no. NM_012656.1). The level of osteonectin mRNA expression was much higher in the 2nd molar germs than in the 3rd molar germs and was found to increase in a time-dependent manner from the early bell stage to the root formation stage in the 2nd molar germs. The pattern of osteonectin protein expression was consistent with these RT-PCR results. Osteonectin protein was found by immunofluorescent analysis to localize in odontoblasts and preodontoblasts rather than the dentin matrix itself. Further studies are needed to validate the involvement of osteonectin in mineralization and root formation.

Ski protein is a nuclear transcription factor that does not bind DNA directly. Due to its unique binding properties with multiple factors, Ski could perform various roles in the regulation of both cellular proliferation and differentiation. We had previously reported that Ski protein is present in granulosa cells of atretic follicles, but not in preovulatory follicles, suggesting that Ski has a role in apoptosis of granulosa cells. The alternative fate of granulosa cells other than apoptosis is to differentiate to luteal cells; however, it is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of the present study was to examine whether the initiation of luteinization with luteinizing hormone (LH) directly regulates expression of Ski in the luteinized granulosa and luteal cells after ovulation by in vitro models. RT-PCR and real time PCR analysis respectively revealed that LH had no effect on c-Ski mRNA expression in the cultured granulosa cells regardless of LH treatment. Though Ski protein isabsent in granulosa cells of preovulatory follicle, its mRNA(c-Ski) was expressed and the level was unchanged even after LH surge. Taken together, these results demonstrated that Ski protein expression is induced in granulosa cells upon luteinization, and suggested that its expression is regulated post-transcriptionally. Moreover, expression of mRNA of Arkadia, an E3 ubiquitin ligases, in luteinizing granulosa cells in vivo was assessed by real time-PCR. The levels of Arkadia mRNA expression were unchanged during follicular growth and post ovulatory luteinization. These findings suggest that Ski protein level may be regulated during luteinization at translational and/or post-translational level but not by Arkadia.

Sloan-Kettering virus gene product of a cellular pro-oncogene c-Ski is an unique nuclear pro-onco protein and belongs to the Ski/Sno proto-oncogene family. Ski plays multiple roles in a variety of cell types, it can induce both oncogenic transformation and terminal muscle differentiation when expressed at high levels. Ski protein is implicated in proliferation/differentiation in a variety of cells. The alternative fate of granulosa cells other than apoptosis is to differentiate to luteal cells, however, it is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of this study was, by means of immunohistochemical methods, to locate Ski protein in the rat ovaries during ovulation and corpora lutea(CL) formation to predict the possible involvement of Ski in luteinization. In addition, to examine whether the initiation of luteinization with luteinizing hormone(LH) directly regulates expression of Ski in the luteinized granulosa and luteal cells after ovulation by in vivo models. In order to examine the expression pattern of Ski protein along with the progress of luteinization, follicular growth was induced by administration of equine chorionic gonadtropin to immature female rat, and luteinization was induced by human chorionic gonadtropin treatment to mimic luteinizing hormone(LH) surge. While no Ski-positive granulosa cells were present in preovulatory follicle, Ski protein expression was induced in response to LH surge, and was maintained after the formation of corpus luteum(CL). These results indicate that Ski is profoundly expressed in the luteinized granulosa cells and luteal cells of CL during luteinization, and suggest that Ski may play a role in luteinization of granulosa cells.

Ski protein is implicated in proliferation/differentiation in a variety of cells. We had previously reported that Ski protein is present in granulosa cells of atretic follicles, but not in preovulatory follicles, suggesting that Ski has a role in apoptosis of granulosa cells. The alternative fate of granulosa cells other than apoptosis is to differentiate to luteal cells; however, it is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of the present study was to locate Ski protein in the rat ovary during luteinizationto predict the possible role of Ski. In order to examine the expression pattern of Ski protein along with the progress of luteinization, follicular growth was induced by administration of equine chorionic gonadtropin to immature female rats, and luteinization was induced by human chorionic gonadtropin treatment to mimic luteinizing hormone (LH) surge. While no Ski-positive granulosa cells were present in preovulatory follicle, Ski protein expression was induced in response to LH surge, and was maintained after the formation of the corpus luteum (CL). Though Ski protein is absent in granulosa cells of preovulatory follicle, its mRNA (c-Ski)was expressed and the level was unchanged even after LH surge. Taken together, these results demonstrated that Ski protein expression is induced in granulosa cells upon luteinization, and suggests that its expression is regulated post-transcriptionally.

This study purposed to examine the effect of low power laser on pain response and axonal regeneration. In order to prepare peripheral nerve injury models, we crushed the sciatic nerve of Sprague-Dawley rats and treated them with low power laser for 21 days. The rats were divided into 4 groups: normal group(n=10); control group(n=10) without any treatment after the induction of sciatic nerve crush injury; experimental group I(n=10) treated with low power laser(0.21mJ/㎟) after the induction of sciatic nerve crush injury; and experimental group II(n=10) treated with low power laser(5.25mJ/㎟) after the induction of sciatic nerve crush injury. We measured spontaneous pain behavior(paw withdrawal latency test) and mechanical allodynia(von Frey filament test) for evaluating pain behavioral response, and measured the sciatic function index for evaluating the functional recovery of peripheral nerve before the induction of sciatic nerve crush injury and on day 1, 7, 14 and 21 after the induction. After the experiment was completed, changes in the H & E stain and toluidine blue stain were examined histopathologically, and changes in MAG(myelin associated glycoprotein) and c-fos were examined immunohistologically. According to the results of this study, when low power laser was applied to rat models with sciatic nerve crush injury for 21 days and the results were examined through pain behavior evaluation and neurobehavioral, histopathological and immunohistological analyses, low power laser was found to affect pain response and axonal regeneration in both experimental group I and experimental group II. Moreover, the effect on pain response and axonal regeneration was more positive in experimental group I to which output 0.21mJ/㎟ was applied than in experimental group II to which 5.25mJ/㎟ was applied.

Recent studies indicate that reactive oxygen species (ROS) are critically involved in persistent pain primarily through spinal mechanisms, and that mitochondria are the main source of ROS in the spinal dorsal horn. To investigate whether mitochondrial ROS can induce changes in mem¬brane excitability on spinal substantia gelatonosa (SG) neurons, we examined the effects of mitochondrial electron transport complex (ETC) substrates and inhibitors on the membrane potential of SG neurons in spinal slices. Application of ETC inhibitors, rotenone or antimycin A, resulted in a slowly developing and slight membrane depolarization in SG neurons. Also, application of both malate, a complex I substrate, and succinate, a complex II substrate, caused reversible membrane depolarization and enhanced firing activity. Changes in membrane potential after malate exposure were more prominent than succinate exposure. When slices were pretreated with ROS scavengers such as phenyl-N-tert-buthylnitrone (PBN), catalase and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), malate-induced depolarization was significantly decreased. Intracellular calcium above 100 µM increased malate-induced depolarization, witch was suppressed by cyclosporin A, a mitochondrial permeability transition (MPT) inhibitor. These results suggest that enhanced production of spinal mitochondrial ROS can induce nociception through central sensitization.

This study was carried out to investigate the toxicity of food Red No.2 in the Sprague-Dawley (SD) female rat for 4 weeks. SD rats were orally administered for 28 days, with dosage of 500, 1,000, 2,000 mg/kg/day. Animals treated with food Red No.2 did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. There were not significantly different from the control group in urinalysis, hematological, serum biochemical value and histopathological examination. In conclusion, 4 weeks of the repetitive oral medication of food Red No.2 has resulted no alteration of toxicity according to the test materials in the group of female rats with injection of 2,000 mg/kg. Therefore, food Red No.2 was not indicated to have any toxic effect in the SD rats, when it was orally administered below the dosage 2,000 mg/kg/day for 4 weeks.

LAR-RPTP (leukocyte common antigen-related receptor protein tyrosine phosphatase) is an important regulator in the nervous system, but little is known about its expression pattern in rat trigeminal ganglion (TG) neurons. To examine whether LAR-RPTP is expressed in the TG in the current study, we sacrificed rats at 0, 7, 10 and 56 day postpartum (dpp) and a second group of rats at 3 and 5 days after an experimental tooth extraction as a TG injury model. RT-PCR was then used to determine the level of LAR-RPTP expression in the TG and immunohistology was employed to detect the subcellular localization of the protein. The mRNA expression of LAR-RPTP during the developmental stages in the TG was found to gradually increase. After experimental tooth extraction however, these transcript levels had significantly decreased at three days. LAR-RPTP protein signals in the TG were found to be cytoplasmic in the normal animals but interestingly, at five days after an experimental tooth extraction, these signals were rare. These results indicate that LAR-RPTP may be regulated during both the developmental as well as regenerative processes that take place in the TG. This further suggests that LAR-RPTP is not only involved in primary axonogenesis but possibly also in the molecular control of axons during TG repair.

This study was conducted to examine the effect of 3,3',4,4',5-pentachlorobiphenyl (PCB 126) on morphological changes in the developing rat testis. PCB 126 (0.2㎎/㎏/week) in corn oil was weekly i.p. injected into rats from 1 to 11 weeks old. The total body weights and testicular weights were measured at 3, 6, 9 and 12 weeks, respectively. The morphological changes in the rat testes were then analyzed by light microscopy (LM) and transmission electron microscopy (TEM). The results demonstrated that PCB 126 treatment caused significant change in the ratio of testicular weight/body weight at 9 week. The treatment of PCB increased the number of pregonium cells at 3 week and it decreased spermatogenesis of the seminiferous tubules at 6 week. The results of this study suggest that PCB 126 can damage the male reproductive organ of the growing rat and that it might be associated with retardation of development of the testis.