목 적: 본 연구는 환경 강화를 다룬 성인 쥐 모델에서의 증거들을 비판적으로 검토하고, 이를 다른 동물 과 인간에게 적용 가능한지에 대해 논의하고자 하였다.
방 법: 연구진은 환경 강화와 관련된 성인 쥐 연구들을 2014년 7월까지 서지 데이터베이스(PubMed, Medline, EMBASE, Web of Science and CINAHL)에서 검색하였고, 포함된 연구들의 참고 문헌에서 본 연 구와 관련된 선행 연구들을 또한 포함시켰다. 방법론적 평가는 본 연구의 세 명의 저자가 독립적으로 구체화 된 요소들을 가지고 시행하였다.
결 과: 포함 및 불포함 기준을 적용하여 최종적으로 15개의 연구가 채택되었다. 모든 포함된 연구들은 일관적으로 시각겉질의 가소성을 증진시킴으로써 성인 쥐에서의 시각 향상의 증거를 보여주었고, 이러한 가 소성을 증진시키는 요소들로는 해부학적 변화에 의한 가소성 재개, 시력 향상, 눈 우세성(ocular dominance)의 변화, 행동적 시력 향상들이 있었다. 이러한 요소들에도 불구하고, 포함된 연구들에서 방법론적 약점들이 내재하고 있다는 것을 발견하였다.
결 론: 본 체계적 문헌 고찰의 결과들을 통해 약시를 가진 성인 쥐의 시각겉질이 결정적 시기가 지났음 에도 불구하고 환경 강화에 대응하여 반응하는 가소성을 가지고 있다는 것을 제안한다. 뿐만 아니라 약시를 가진 성인 시각겉질에 환경 강화를 적용하여 시각계의 재활을 도울 수 있을 것으로 간주되지만, 이를 위해서는 인간을 포함한 다른 동물들 간의 해부학적 및 생활방식의 차이들을 극복해야만 가능하다고 본다.
The activation of glial cells in the spinal cord has been contribute to the initiation and maintenance of pain facilitation induced by peripheral inflammation and nerve injury. The present study investigated effects of botulinum toxin type A (BoNT-A), injected subcutaneously or intracisternally, on the expression of microglia and astrocytes in rats. Complete Freund’s Adjuvant (CFA)-induced inflammation was employed as an orofacial chronic inflammatory pain model. A subcutaneous injection of 40 μL CFA into the vibrissa pad was performed under 3% isoflurane anesthesia in SD rats. Immunohistochemical analysis for changes in Iba1 (a microglia marker) and GFAP (an astrocyte marker), were performed 5 days after CFA injection. Subcutaneous injection of CFA produced increases in Iba1 and GFAP expression, in the ipsilateral superficial lamia I and II in the medullary dorsal horn of rats. Subcutaneous treatment with BoNT-A attenuated the up-regulation of Iba1 and GFAP expressions induced by CFA injection. Moreover, intracisternal injection of BoNT-A also attenuated the up-regulated Iba1 and GFAP expressions. These results suggest that the anti-nociceptive action of BoNT-A is mediated by modulation activation of glial cells, including microglia and astrocyte.
Streptozotocin(STZ)으로 유도된 당뇨 흰쥐에게 연교의 에탄올 추출물을 1일 1회 7일간 1,000㎎/㎏.b.w의 용량으로 투여 후 glucose함량과 이에 관여하는 효소(glucokinase(GK), glucose-6-phosphatase(G-6-Pase), glucose-6-phosphate dehydrogenase(G-6-PDH)활성과 glycogen 함량, triglyceride(T.G), total cholesterol등의 지질대사에 관여하는 물질들의 함량을 측정한 결과 연교 에탄올 추출물 투여군이 glucose, T.G, total cholesterol 등의 함량과 G-6-Pase 활성이 유의적인 감소를 나타내었으며 glycogen 함량과 GK의 활성이 유의적인 증가를 나타내었다. 이와 같이 연교 에탄올 추출물을 1,000㎎/㎏.b.w을 당뇨 흰쥐에게 투여한 결과 혈당저하, 지질대사의 개선 효과를 갖는 유효성분을 함유하고 있음을 알 수 있었다.
In the present study, we investigated the effect of staurosporine on the formation of cellular processes in human gingival fibroblasts and rat astrocytes. Staurosporine caused a rapid induction of process formation in human gingival fibroblasts and rat astrocytes in a concentration dependent manner. The process formation of human gingival fibroblasts and rat astrocytes was prevented by the pretreatment with N-acetylcysteine, suggesting that staurosporine-induced ROS production was responsible for the process formation. Colchicine, a microtubule depolymerizing agent, inhibited the staurosporine-induced process formation, whereas cytochalasin D, an actin filament breakdown agent, failed to suppress the formation of cellular processes. This result indicated that polymerization of microtubule, and not actin filament, was responsible for the formation of cellular processes induced by staurosporine. In support of this hypothesis, Western blot analysis was conducted using anti-tubulin antibody, and the results showed that the amount of polymerized microtubule was increased by the treatment with staurosporine while that of depolymerized beta-tubulin in soluble fraction was decreased. These results indicate that staurosporine induces ROSmediated, microtubule-dependent formation of cellular processes in human gingival fibroblasts and rat astrocytes.
Lipoxygenase(LOX) 결여 콩으로 제조한 두부의 급이가 5주간의 고지방-콜레스테롤 식이성 흰쥐에서 간 조직과 분변 지질 함량 및 생체 내 항산화계에 미치는 영향을 평가하였다. 실험군은 정상군, 고지방-콜레스테롤 급이군(HFC), 고지방-콜레스테롤 식이+두부 급이군(태광 두부 급이군, HFC-T1; 개척#1 두부 급이군, HFC-T2; 진양 두부 급이군, HFC-T3)으로 구분하였다. 두부의 콜레스테롤 흡착활성은 개척#1 두부가 타 시료에 비해 유의적으로 높았다. 두부 급이군의 비만지수는 대조군에 비해 통계적인 유의차는 없었으나, 개척#1 두부 급이군(HFC-T2)의 비만지수가 가장 낮았다. 간 조직의 총 지질 함량은 정상군에 비해 대조군이 5.9배 증가되었으며, 개척#1 두부 급이군(HFC-T2)은 대조군에 비해 유의적으로 감소되었다. 대조군에 비해 중성지방 함량은 개척#1, 진양 두부 급이군에서 유의적으로 낮았으며, 총 콜레스테롤 함량은 두부 급이군에서 모두 유의적으로 감소되었다. 두부 급이군의 분변 중 총 지질 함량은 대조군에 비해 유의적으로 증가되었으나, 두부의 종류에 따른 유의차는 없었다. 중성지방 함량은 개척#1 두부 급이군에서 가장 많았고, 총 콜레스테롤의 배출량은 대조군에 비해 두부 급이군에서 다소 증가되었으나, 통계적인 유의차는 없었다. 지질과산화물 함량은 대조군에 비해 HFC-T2 및 HFC-T3군에서 유의적으로 감소되었다. DPPH 라디칼 소거활성은 HFC-T2군에서 정상군과 유사한 수준까지 상승하였다. 간 조직에서 SOD 활성은 대조군에 비해 두부 급이군에서 1.4~2.2배 증가되었으며, HFC-T3군에서 활성이 가장 높았다. Catalase, GSH-Px 및 UDPGT 활성은 개척#1 두부 급이군에서 유의적으로 높았다. LOX 결여 콩으로 제조한 두부의 섭취는 고지방-콜레스테롤 식이에 대해 체내 지질 수준 저하 및 항산화 활성에 긍정적인 효과를 가질 것으로 생각된다.
Reactive oxygen species (ROS) and nitrogen species (RNS) are implicated in cellular signaling processes and as a cause of oxidative stress. Recent studies indicate that ROS and RNS are important signaling molecules involved in nociceptive transmission. Xanthine oxidase (XO) system is a well-known system for superoxide anions (O2˙-) generation, and sodium nitroprusside (SNP) is a representative nitric oxide (NO) donor. Patch clamp recording in spinal slices was used to investigate the role of O2˙- and NO on substantia gelatinosa (SG) neuronal excitability. Application of xanthine and xanthine oxidase (X/XO) compound induced membrane depolarization. Low concentration SNP (10μM) induced depolarization of the membrane, whereas high concentration SNP (1 mM) evoked membrane hyperpolarization. These responses were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger). Addition of thapsigargin to an external calcium free solution for blocking synaptic transmission, led to significantly decreased X/XO-induced responses. Additionally, X/XO and SNP-induced responses were unchanged in the presence of intracellular applied PBN, indicative of the involvement of presynaptic action. Inclusion of GDP-β-S or suramin (G protein inhibitors) in the patch pipette decreased SNP-induced responses, whereas it failed to decrease X/XO-induced responses. Pretreatment with n-ethylmaleimide (NEM; thiol-alkylating agent) decreased the effects of SNP, suggesting that these responses were mediated by direct oxidation of channel protein, whereas X/XO-induced responses were unchanged. These data suggested that ROS and RNS play distinct roles in the regulation of the membrane excitability of SG neurons related to the pain transmission.
Taste is an important sense in survival and growth of animals. The growth and maintenance of taste buds, the receptor organs of taste sense, are under the regulation of various neurotrophic factors. But the distribution aspect of neurotrophic factors and their receptors in distinct taste cell types are not clearly known. The present research was designed to characterize mRNA expression pattern of neurotrophic factors and their receptors in distinct type of taste cells. In male 45-60 day-old Sprague-Dawley rats, epithelial tissues with and without circumvallate and folliate papillaes were dissected and homogenized, and mRNA expressions for neurotrophic factors and their receptors were determined by RT-PCR. The mRNA expressions of brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), receptor tyrosine kinase B (TrkB), exclusion of nerve growth factor (NGF), neurotrophin-4/5 (NT4/5), receptor tyrosine kinase A (TrkA), receptor tyrosine kinase C (TrkC), and p75NGFR were observed in some population of taste cell. In support of this result and to characterize which types of taste cells express NT3, BDNF, or TrkB, we examined mRNA expressions of NT3, BDNF, or TrkB in the PLCβ2 (a marker of Type II cell)- and/or SNAP25 (a marker of Type III cell)-positive taste cells by a single taste cell RT-PCR and found that the ratio of positively stained cell numbers were 17.4, 6.5, 84.1, 70.3, and 1.4 % for PLCβ2, SNAP25, NT3, BDNF, and TrkB, respectively. In addition, all of PLCβ2- and SNAP25-positive taste cells expressed NT3 mRNA, except for one taste bud cell. The ratios of NT3 mRNA expressions were 100% and 91.7% in the SNAP25- and PLCβ2-positive taste cells, respectively. However, two TrkB-positive taste cells co-expressed neither PLCβ2 nor SNAP 25. The results suggest that the most of type II or type III cells express BDNF and NT3 mRNA, but the expression is shown to be less in type I taste cells.
Renal dysplasia is a developmental disorder of the renal parenchyma involving anomalous differentiation. It is characterized by persistent metanephric ducts surrounded by primitive mesenchyme, fetal or immature glomeruli, fetal or immature tubules, interstitial fibrosis, and dysontogenic metaplasia involving tissues such as cartilage. Renal dysplasia has been rarely reported in rats. Here, we observed a small left kidney in a rat used in a short-term repeat toxicity study. The rat showed no clinical signs throughout the study. All parameters, including those reflecting kidney functions, were normal upon hematological examination and urinalysis. Grossly, the kidney was small (5 × 8 mm) and its surface appeared normal. Histological examination revealed that the cortex and medulla were poorly demarcated and contained immature/atrophic glomeruli, immature renal tubules, and mesenchymal cells. The cortex contained immature glomeruli, atrophic glomeruli with cystic dilatation of Bowman’s capsular space, and some atypical tubules. Primitive metanephric tubules in the medulla were larger in diameter than normal collecting ducts, lined by a tall columnar epithelium with pale cytoplasm and basal nucleus, and surrounded by loose mesenchymal cells. Occasional tubules contained pale eosinophilic homogenous material in the lumen. Thus, this was diagnosed as a case of renal dysplasia on the basis of histologic features and is the first reported case of renal dysplasia in Sprague Dawley rats.
The current study was conducted to evaluate the biocompatibility of α-1,3 galactosyltransferase knockout pig bone graft in a rat calvarial defect model. Porcine cancellous bones were harvested from general and alpha-gal KO pigs and washed with 70% ethanol solution and normal saline. Bone pieces of the alpha-gal KO pig underwent a chemical treatment process to delipidize and deproteinize the bone. Bone graft particles were freeze-dried and stored at −70°C until use. Each bone graft was implanted into the rat calvarial defect in a fresh general pig, fresh transgenic pig, and chemical-treated pig bone group. There was no systemic adverse effect on hematology or necropsy findings in all groups at 1 week and 4 weeks. In the microcomputed tomography analysis, bone volume increased significantly in the chemical-treated transgenic pig bone group, whereas bone mineral density decreased significantly in the fresh general pig bone group compared with other groups. Histological evaluation showed cellular infiltration located at the margin of the bone graft particles, especially in the fresh general pig bone group. These results indicate that fresh general pig bone can elicit a greater local inflammatory response than fresh transgenic pig bone. Further, chemical-treated transgenic pig bone graft was less immunogenic than fresh bone graft. In conclusion, transgenic pig bone is a more biocompatible graft material. In addition, chemical treatment can reduce bone graft immunogenicity by delipidizing and deproteinizing bone.
오늘날 현대인들의 식생활방식 중 과다한 열량의 영양소 섭취로 인하여 초래되는 비만의 유발 원인 중의 하나로 알려진 고지혈증(hyperlipidemia)에 대한 예방효과가 있는 것으로 알려진 전통방식으로 제조된 고추장의 생리활성 기능성 효과를 분석하고자 하였다. 이 연구에서는 실험동물로서 Sprague-Dawley(SD)-Rat에 대해서 고추장 추출물의 건강증진 효과에 대해서 실험동물을 사용하여 직접 확인하고 시도하였다. 실험군은 실험동물용 일반사료만을 먹인 음성대조군 그룹(N-group)과 일반사료와 고추장 추출물을 동시에 먹인 시험그룹(K-group) 그리고 양성대조군으로 고콜레스테롤 사료만을 먹인 그룹(H-group)으로 구분하여 5주간 사육하면서 건강증진효과의 발현에 대해서 분석하 였다. 3그룹의 실험동물을 5주간의 사육 후 해부했을 때 H-group의 모든 동물(100%)에서 공통적으로 심한 지방간 (fatty liver) 소견이 관찰되었으나, N-group이나 K-group의 어떠한 동물에서도 지방간 소견은 관찰되지 않았다. 한편, 실험동물의 혈장성분에 대한 혈액생화학적 성적의 비교에서는 고지혈증의 예방에 유익한 성분으로 알려진 HDL의 경우, 고추장 추출물 투여 그룹(25±8.43 ㎎/㎗)은 H-group(22.6±4.16) 보다 다소간 상승된 수치를 보였으나, 특히 고지혈 증을 악화시키는 원인으로 알려진 LDL 경우에는 H-group (55.8± 44.8 ㎎/㎗)이 고추장 추출물 투여 그룹(8.6±1.52 ㎎/㎗)과 음성대조군인 N-group(9.8±2.39)의 성적보다도 유의적으로 높은 수치를 나타냈다. 결과적으로 이 연구에서 SD-Rat에 투여했던 고추장 추출물은 실험동물에서 건강기능 개선효과의 하나인 저지방혈증 효과를 발현한 것으로 사료되었다.
The anti-inflammatory effects of the glycosaminoglycan (GAG) derived from cricket (G. bimaculatus, Gb) were investigated in complete Freund’s adjuvant (CFA) treated chronic arthritis rat model. This GAG produced a meaningful anti-edema effect showing inhibition of C-reactive protein (CRP) and rheumatoid factor. This GAG also inhibited the atherogenesis and pro-inflammatory cytokine levels of VEGF production in HUVEC cells, IL-6, prostaglandin E2 stimulated lipopolysaccharide in LAW 264.7 cells and TNF-α production in normal splenocytes, with dose dependent manner. This GAG was also found to be an inducer of NO production from the HUVEC cells and a stimulator of endothelial nitric oxide synthase. In the histological finding, the LV dorsal root ganglion, linked to the paw treated Gb GAG, was repaired against CFA induced cartilage destruction. The combined Indomethacin (5 mg/kg)-Gb GAG (10 mg/kg) also more effectively inhibited CFA-induced paw edema at 3h, 2nd and 3rd day to levels comparable to anti-inflammatory drug, indomethacin.
Mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) are widespread contaminants of food and feedstuffs. It is very likely, that humans and animals are always exposed to mixtures of mycotoxins rather than to individual compounds. Therefore, risk assessments should consider mixture toxicity data. In the present study the combination of AFB1, OTA and ZEA was tested for genotoxicity in rat bone marrow and blood leukocytes after 15, 30 and 60 days treatment. The level of DNA damage was determined by the comet assay. The tail intensity and Olive tail moment in leukocytes and bone marrow cells were significantly higher than in controls. At the same time, the level of DNA damage in bone marrow cells was higher than in leukocytes. The data suggests that prolonged exposure to mycotoxins combination through food consumption can induce DNA damage contributing to the harmful effects in vivo.
The current study was conducted in order to investigate bone formation using matrigel and angiogenic factors with HA and poly ε-caprolactone (HA/PCL) in a rat calvarial defect model. Calvarial defect formation was surgically created in Sprague Dawley rats (n=36). Rats in the control group (CD group, n=6) did not receive a graft. The HA/ PCL scaffold was grafted with matrigel (M-HA/PCL group, n=6) or without matrigel (HA/PCL group, n=6); and 100 ng of vascular endothelial growth factor with HA/ PCL scaffold containing matrigel (VEGF100 group, n=6), 100 ng (PDGF100 group, n=6) and 300 ng (PDGF300 group, n=6) of PDGF with HA/PCL scaffold containing matrigel were grafted in calvarial defects, respectively. Four weeks after surgery, bone formation was evaluated with micro computed tomography (micro CT) scanning, and histologically. According to the results, bone mineral density was significantly increased in the VEGF100, PDGF100, and PDGF300 groups compared to the HA/PCL group, in which angiogenic factors were not applied. In histological evaluation, more new bone formation around scaffolds was observed in the PDGF100 and the PDGF300 groups, compared with the VEGF100 group. Thus, the results indicate that HA/PCL containing matrigel with VEGF and PDGF is an effective grafting material for enhancement of bone formation in critical-sized bone defects. Especially, due to its price and capacity for bone formation, PDGF may be more effective than VEGF.
Onion (Allium cepa L.) contains high levels of dietary fibers and antioxidants, including vitamin C, D, and folates. Onion is also known as a quercetin-rich vegetable with high flavonoid content. Onion peel contains over 20 times more quercetin than onion flesh. The aim of this study was to examine the question of whether onion peel extract supplementation has an effect on maximal exercise performance in rat. Onion peel extracts were extracted with hot water. Thirty male Sprague Dawley rats were maintained on a pellet diet for one week, and then randomly divided into five groups: Normal control, Positive control (quercetin 20 mg/kg), Onion peel 4 mg/kg, Onion peel 20 mg/kg, and Onion peel 100 mg/kg. Oral administration was performed daily. The experimental period was four weeks. Thereafter, animals were then forced to swim in water and the maximal exercise performance period from the swimming start time to the exhausted time, in which they failed to rise to the surface of the water to breathe within a 7 second period, was measured. After necropsy, weights of gastrocnemius muscles were measured. Lactate dehydrogenase concentration in serum was measured using an enzymatic method, using a commercial kit. The maximal exercise performance period was significantly longer in the onion peel extracts fed groups, compared with the control group. The lactate dehydrogenase concentration of the onion peel extracts fed groups was significantly lower, compared with the control group. Based on these results, we suggest that onion peel water extract supplementation can enhance exercise capacity caused by the mechanism of decreasing lactate dehydrogenase concentration.
본 연구는 Sprague-Dawley 흰쥐 16마리를 이용하여 흰쥐 복강 및 피하지방 감소 후보 항체가 체중, in vivo 타장기 안전성 및 혈액성상 등 영양생리대사에 미치는 영향을 조사하고자 실시하였다. 무처리구(control), 비면역항체 처리구(NAb), 면양을 이용하여 기 개발된 흰쥐 복강(AAb) 및 피하지방 감소 후보항체(SAb)를 복강 주사하였을 때 주사 후 1주차에 SAb 처리구에서 사료 및 물 섭취량의 일시적인 감소가 나타났으나 그 이후에는 정상적으로 회복되는 것으로 보아 항체의 효과보다는 개체 차이에 기인하는 것으로 판단된다. 흰쥐 체중의 경우 항체 주사 처리 전․후 및 실험구 간 통계적인 유의차는 나타나지 않았다(p>0.05). SAb 처리구에서 나타난 주사 처리 후 1-2주 동안 일시적인 체중 감소 현상이 발생했으나, 통계적 유의성은 없었다(p>0.05). 후보 항체 주사 시 흰쥐 AAb 처리구는 control과 비교해서 생체 신장의 무게가 유의적으로 낮은 것으로 나타났다(p<0.05). 하지만, NAb 처리구의 신장 무게 역시 유의적인 감소를 보여(p<0.05) 결국 AAb 처리구의 신장 무게 감소는 주사에 의한 스트레스 또는 개체 간의 변이 때문인 것으로 생각된다. 신장을 제외하고는 후보 항체에 의한 주요 장기들(심장, 간장, 폐 및 비장)의 무게에는 실험구 간 유의적인 차이가 나타나지 않았다(p>0.05). 후보 항체에 의해 혈중 glucose, triglyceride 및 total cholesterol 농도에는 실험구 간 유의적인 변화가 나타나지 않았으며(p>0.05), 각 혈액대사물질의 농도는 일반적인 수준으로 나타났다. 이상의 결과를 볼 때, 본 연구에서 이용된 흰쥐AAb 및 SAb는 in vivo 영양생리대사에 부정적 영향을 미치지 않는 안전한 항체로 판단된다.
This study is intended to examine the tDCS and Morris Water maze training in Alzheimer’s disease(AD) rats on Tau protein expression. Experiment groups were divided into four groups and assigned 16 rats to each group. Group Ⅰ was a control group(AD induced by scopolamine); Group Ⅱ was a experimental control group(AD injured by scopolamine and treatment tacrine); Group Ⅲ was a group of tDCS application after AD injured by scopolamine; Group Ⅳ was a group of morris water maze training after AD injured by scopolamine. In cognition test, the outcome of group Ⅱ was significantly lower than the groups(p<.001). and group Ⅲ, Ⅳ were significantly low result at 14 days(p<.05). In histological finding, the experimental groups were destroy of micro vessels and finding of cell atropy and swelling. Group Ⅲ, Ⅳ were decreased in degeneration of liver and kidney cells. In immuno- histochemistric response of BDNF and tau protein in hippocampus, BDNF expression of Group Ⅱ was more increase than the other groups. and increase of BDNF expression was Ⅲ, Ⅳ were higher than group Ⅰ at 21 days. Tau protein expression of Group Ⅱ was more decrease than the other groups. and decrease of Tau protein expression was Ⅲ, Ⅳ were lower than group Ⅰ at 21 days. These result suggest that improved tDCS and morris water maze training after scopolamine induced is associated with dynamically altered expression of BDNF and Tau protein in hippocampus and that is related with cognitive function.
Recent studies indicate that reactive oxygen species (ROS) can act as modulators of neuronal activity, and are critically involved in persistent pain primarily through spinal mechanisms. In this study, we investigated the effects of NaOCl, a ROS donor, on neuronal excitability and the intracellular calcium concentration ([Ca2+]i) in spinal substantia gelatinosa (SG) neurons. In current clamp conditions, the application of NaOCl caused a membrane depolarization, which was inhibited by pretreatment with phenyl-N-tert-buthylnitrone (PBN), a ROS scavenger. The NaOCl-induced depolarization was not blocked however by pretreatment with dithiothreitol, a sulfhydrylreducing agent. Confocal scanning laser microscopy was used to confirm whether NaOCl increases the intracellular ROS level. ROS-induced fluorescence intensity was found to be increased during perfusion of NaOCl after the loading of 2′,7′-dichlorofluorescin diacetate (H2DCF-DA). NaOCl-induced depolarization was not blocked by pretreatment with external Ca2+ free solution or by the addition of nifedifine. However, when slices were pretreated with the Ca2+ ATPase inhibitor thapsigargin, NaOCl failed to induce membrane depolarization. In a calcium imaging technique using the Ca2+-sensitive fluorescence dye fura-2, the [Ca2+]i was found to be increased by NaOCl. These results indicate that NaOCl activates the excitability of SG neurons via the modulation of the intracellular calcium concentration, and suggest that ROS induces nociception through a central sensitization.
The deleted in colorectal cancer (DCC) protein mediates attractant responses to netrin during axonogenesis. In the rat trigeminal ganglia (TG), axons must extend toward and grow into the trigeminal nerve to innervate target tissues such as dental pulp. Our present study aimed to investigate the exp- ression of DCC in the TG. Four developmental timepoints were assessed in the experiments: postnatal days 0, 7 and 10 and adulthood. RT-PCR and western blotting revealed that the expression of DCC mRNA and protein does not signi- ficantly change throughout development. Immunohistoche- mistry demonstrated that DCC expression in the TG was detectable in the perikarya region of the ganglion cells du- ring development. Nerve injury at 3 and 5 days after the man- dibular nerve had been cut did not induce altered expression of DCC mRNA in the TG. Moreover, DCC-positive cell bodies also showed similar immunoreactive patterns after a nerve cut injury. The results of this study suggest that DCC constituti- vely participates in an axonogenesis attractant in ways other than expression regulation.
The effects of the an immunosuppressive drug cyclos- porine A (CsA), on the salivary gland are largely unknown, even though clinical trials for the stimulation of salivation using CsA have been attempted. Cyclophilin A (CypA) is known to be a binding protein for CsA. CypA has cell proliferation and tissue matrix change activities. In our present study, the presence of CypA in the gland and effects of CsA on CypA expression were investigated by immu- nohistochemistry, immunoblotting and RT-PCR analyses. CypA was immunohistochemically detected in various kinds of ducts in the submandibular glands of Sprague Dawley rats. The CypA mRNA level was highest at postnatal day 1 and gradually decreased in a time-dependent manner up to adulthood. The expression of CypA increased after a 10 day subcutaneous administration of CsA in postnatal day 1 rats. Surgical sections of the chorda-lingual nerve with impaired salivation showed no changes in CypA expression. A cell proliferation assay using PCNA anti-serum showed inc- reased cell division following CsA treatment. These results suggest that CsA and CypA may act on ductal cells to regulate saliva composition rather than salivation levels.