• 치과방사선
• /
• 제26권2호
• /
• pp.75-90
• /
• 1996

The purpose of this study was to observe microscopic change of salivary gland tissue, which is a cause of xerostomia in diabetic condition; for this target, the author injected streptozotocin 0.1ml/100 gm b.w. on the rat, Sprague Dawley, to induce diabetes, and then observed microscopic changes in parotid gland tissue using light microscopy and electron microscopy. The results were as follows : 1. Parotid gland tissue of the diabetic rat was atrophied or degenerated in lapse of experimental time, but began to repair from 14 days after diabetic induction. 2. In the basal lamina of the vessel of parotid gland tissue in the diabetic rat, lamina lucida was discontinued and lamina densa was increased in thickness, but the number of capillary was gradually increased and dilated. 3. In acinic and intercalated ductal cells of parotid gland in the diabetic rat, changes of mitochondria, RER, secretory granule, free ribosome were prominent. In conclusion, the present study demonstrated that degenerative changes of the parotid gland tissue were due to not completely thickening of the basal lamina of vessels, but many other causal factors, because thickness of the basal lamina of vessels was not related with degenerative changes.

• 한국항공운항학회지
• /
• 제20권3호
• /
• pp.63-67
• /
• 2012

Spaceflight induces a number of cardiovascular physiological alterations. To study adaptations to microgravity on Earth, the tail-suspended, hindlimb-unloaded rat model has been used to simulate the effects of microgravity. Despite the extensive use of this model to infer physiological adaptations of many organs to microgravity, little information has been obtained on the effect of tail suspension(TS) on cardiac adaptations in the rat. This study was aimed to investigate the effects of simulated microgravity on the rat myocardium using the TS model. Twenty-four male Sprague-Dawley rats were randomly assigned to 3 experimental groups(1, 7 and 14 days of TS) and a control group. A microscopic examination was performed to assess histopathological changes in the myocardial morphology. The hearts from the control group, the 1 day-TS rats and the 7 day-TS rats revealed no evident abnormalities in cardiomyocyte size and morphology. At day 14 of TS, in contrast, the ventricular cardiomyocytes appeared more separated from each other and were slightly smaller in size compared with those of the control group. Also seen were scattered areas exhibiting focal disorganization of muscle fibers and some degenerating cardiomyocytes, of which the nuclei had become pyknotic or disappeared. In this study, we demonstrated that the ventricular cardiomyocytes underwent degeneration and atrophy at the microscopic level during exposure to simulated microgravity in TS rats.

• Journal of Acupuncture Research
• /
• 제39권4호
• /
• pp.239-248
• /
• 2022

To determine the effect of Korean medicine treatment of avascular necrosis of the femoral head (ANFH) this study reviewed both single ingredients and bioactive compounds in the treatment of ANFH in a rat model. Literature was retrieved from PubMed and Google Scholar using the keywords "femur head necrosis," "natural extract," and "rat." The data from studies analyzed included: rats' characteristics, development methods of ANFH, natural extracts administration, observation methods, and outcome indicators. Two independent researchers screened all articles retrieved and 26 studies were chosen. The most used rat species was the Sprague Dawley rat (76.9%). To induce ANFH, steroid injections (46.2%), and oral gavage (53.8%) were typically used. Studies focused mainly on factors affecting bone formation (65.3%), and apoptosis (53.8%). Research on ANFH focused on using traditional natural substances mentioned in classical literature to confirm its effectiveness against anti-inflammation, osteogenesis, and cell death. ANFH has a diverse etiology, therefore research models such as genetic analysis of human-derived samples from ANFH patients may shed more light on the condition. Moreover, research into herbal medicines and pharmacoacupuncture treatment of ANFH should precede.

• Journal of Periodontal and Implant Science
• /
• 제30권4호
• /
• pp.835-852
• /
• 2000

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue and repair of function. For more than a decade there have been many efforts to develop materials and methods of treatment to promote periodontal wound healing. Recently many efforts are concentrated on the regeneration potential of material used in oriental medicine. In some in vitro and in vivo experiments, there have been many evidences that these materials have an effect on bone regeneration. The purpose of this study was to evaluate histologically and radiologically in Sprague-Dawley rats the effects of safflower seed extracts on the regeneration of the calvarial defects surgically produced. So in this study, the critical size defects were surgically produced in the calvarial bone of 30 Sprague-Dawley rats using the 8mm trephine bur. The safflower seed extract was applied into the defect of each rat in experimental group, whereas nothing was applied into the defect of each rat in control group. Rats were sacrificed at 2, 4, 8 weeks following operation and histomorphometric and radiodensitometric analysis were performed. 1. The newly formed bone length was $102.91{\pm}22.05$, $178.29{\pm}24.40$ at 2 week in the each control, experimental group, $130.95{\pm}39.24$, $242.62{\pm}50.33$ at 4 week and $181.53{\pm}76.35$, $240.36{\pm}22.00$ at 8 week($unit,{\mu}m$). In the 2, 4 week, there were statistically significant difference between control and experimental group(P<0.05). 2. The newly formed bone area was $2962.06{\pm}1284.48$, $10648.35{\pm}1284.48$ at 2 week, $5103.25{\pm}1375.88$, $9706.78{\pm}1481.81$ at 4 week, $8046.02{\pm}818.99$, $12057.06{\pm}740.47$ at 8 week($unit,{\mu}m^2$). In every week, there were statistically significant difference between control and experimental group(P<0.05). 3. The radiopacity was $14.26{\pm}.33$, $25.47{\pm}4.33$ at 2 week, $20.06{\pm}9.07$, $26.61{\pm}2.78$ at 4 week, $22.99{\pm}3.76$, $27.29{\pm}1.54$ at 8 week(unit, %). In the 2 week, there was statistically significant difference between control and experimental group(P<0.05). In conclusion, the results of the present study suggest that safflower seed extract initially has an effect on the newly formed bone area, length and radiopacity when it is applied to the calvarial defect of Sprague - Dawley rat. Then. the material has an effect on newly formed bone area and length.

• Journal of Periodontal and Implant Science
• /
• 제26권3호
• /
• pp.771-778
• /
• 1996

The assessment of alveolar bone changes on dental radiographs to indicate progression of periodontal diseases or healing response to therapy is routine procedure. However, the diagnostic accuracy in detecting small alveolar bone changes is very limited. Recently, guided bone regeneration therapy is popular, but the quantification of new bone is somewhat difficult with conventional evaluation method. To quantificate the amount of new bone, various evaluating methods have been introduced including histomorphometry, radiomorphometry, biochemical analysis, X-ray probe microanalysis, scanning electron microscope backscatter method. In this study, guided bone regeneration using resorbable membrane with & without PDGF-BB is quatificated through histomorphmetry to evaluate the efficacy of histomorphometric analysis. 4 beagle dogs and 8 Sprague-Dawley rats were selected as experimental animals. In beagle dog experiment, $4{\times}4mm$ Class II defects were created in maxillary both second premolars, and biodegradable membrane containing PDGF-BB(experimental group) were covered over one defect, and same membrane without PDGF-BB(control group) were covered over the other defect. At 2 weeks, 5 weeks after surgery, each beagle dogs were sacrificed, and the tissues were treated by undecalcified fixation. In Sprague-Dawley rat experiment, 5mm round defect were created in temporal bone, the same membranes were covered on the defects. At 1 week, 2 weeks after surgery, each rats were sacrificed, and undecalcified fixation were taken. After grinding tissue specimen, we analyse them histomorphometrically using image analysis system. In beagle dog 2 weeks specimens, new bone formation area were $0.03123mm^2$ in experimental group,and $0.03012mm^2$ in control group. At 5 weeks specimens, $0.15324mm^2$ in experimental group, and $0.09123mm^2$ in control group. In Sprague-Dawley rat specimens, new bone fomation area were $0.20448mm^2$ in 1 week experimental group, $0.03604mm^2$ in 1 week control group. At 2 weeks specimens, $0.46349mm^2$ in experimental group, $0.17741mm^2$ in control group. The results indicated that histomorphometric analysis of new bone formation using image analysis system is very effective quantification method to evaluate the efficacy of treatment modalities.

• 대한수의학회지
• /
• 제43권4호
• /
• pp.541-549
• /
• 2003

The present study investigated the effects of aging on Leydig cells of Sprague Dawley rats. Rats of 3, 6, 12 and 18 months of age were used. Testes of rat were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in epon-araldite. Using $1{\mu}m$ sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Testis incubations were used to determine luteinizing hormone (LH; 100 ng/ml) stimulated testosterone secretory capacity per testis in vitro. Testosterone levels in the incubation medium, and testosterone and luteinizing hormone levels in serum of these four groups of rats were determined by radioimmunoassay. Morphological studies revealed that Leydig cells were more abundant in the testis interstitium at 6, 12 and 18 months when compared with 3 months. The volumes of Leydig cells per testis was significantly higher, at 6, 12 and 18 months of age than those at 3 months. The number of Leydig cells per testis was doubled at 6, 12 and 18 months of age compared with 3 months. The average volume of a Leydig cell was not significantly different between 3 and 6 months of age, however, at 12 and 18 months a significantly lower value was observed. LH-stimulated testosterone production per testis in vitro was reduced by 45% at 6 months of age compared with 3 months; a further significant reduction was observed at 12 and 18 months. Serum testosterone and LH levels were not significantly different between 3 and 6 months of age but at 12 and 18 months a significantly lower value was observed in both groups for these hormones. These results showed that signs of aging are apparent in Leydig cells of Sprague Dawley rats at 12 months of age.

• 한국식품영양과학회지
• /
• 제37권9호
• /
• pp.1120-1125
• /
• 2008

괴각 추출물을 농축하여 동결 건조해서 실험동물인 Sprague-dawley rats의 해당 식이에 0.5% 수준으로 첨가하여 4주간 사육하면서 체중은 3일 간격으로 섭취는 2일 간격으로 일정한 시각(오전 9시)에 측정하였으며, 활성산소 및 항산화 활성 측정은 2주 간격으로 측정하였다. 또한 실험이 종료된 후 실험동물을 단두 도살하여 혈청 중 total cholesterol, HDL-cholesterol, triglyceride, glucose, phospholipid를 측정하여 지질함량에 미치는 영향을 측정한 결과 아래와 같은 결론을 얻었다. 괴각 추출물을 Sprague dawley rats에 급여 후 식이섭취량, 식이효율 및 체중증가량을 측정한 결과 각 군 간에 차이를 보이지 않았으며 2주 간격으로 항산화 활성 및 활성산소를 측정한 결과 2주째부터 항산화에서 차이를 보였으며 활성산소 생성량은 대조군과 비교했을 때 큰 차이가 없었다. 4주 후 괴각 추출물 급여군의 항산화 값은 대조군에 비해 17.04%로 높게 나타났다. 실험식이 종료 후 실험동물에서 적출한 장기의 무게를 측정한 결과 심장, 신장, 장, 간 모두 커다란 차이를 보이지 않았다. 또한, 혈청중의 total cholesterol 함량 측정 결과 괴각 추출물 급여군이 대조군에 비해 낮은 함량을 나타내었고, HDL-cholesterol 함량에서는 대조군에 비해 높은 함량을 보였다. Triglyceride 함량은 거의 차이가 없었으며 glucose 함량은 대조군에 비해 낮았고, phospholipid 함량은 높았으나 차이가 없었다. 이상에서와 같이 괴각 추출물을 이용한 동물실험에서 항산화 활성 및 혈청의 지질대사에 개선 효과가 있음을 확인하였다. 향후 이들 추출물을 항산화활성 및 지질대사 개선에 기능성을 갖는 식품소재로의 이용 가능성이 기대되며 향후에 추출물 투여농도의 증가나 투여기간의 연장에 따른 추가적인 연구가 필요하다고 사료된다.

• Toxicological Research
• /
• 제13권1_2호
• /
• pp.131-138
• /
• 1997

Group of 40 male and 40 female Sprague-Dawley rats were given daily intravenous injections of different dosage of Erythropoietin (EPO), 80 IU/ kg/day (low dosage group), 400 IU/ kg/day (middle dosage group), or 2000 IU /kg/day (high dosage group)for 4 weeks by tail vein according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Appearance, behavior, mortality, and food consumption of rats of treated groups were not affected during the experimental periods. No significant EPO (erythropoietin)-related changes were found in urinalysts, eye examination, hematology, serum chemistry, and organ weight. No histopathological lesions were observed in both control and treatment groups. Our results strongly suggest that no toxic changes were found in rat treated intravenously with EPO (erythropoietin)for 4 weeks.

• 약학회지
• /
• 제58권4호
• /
• pp.223-228
• /
• 2014

The present study was undertaken to investigate the influence of sulforaphane on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that sulforaphane, the primary ingredient of broccoli of cruciferous vegetables, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Intact of denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, sulforaphane significantly inhibited fluoride, phorbol ester or thromboxane $A_2$ mimetic-induced contraction in denuded muscles suggesting that additional pathways different from endothelial nitric oxide synthesis such as inhibition of Rho-kinase or MEK might be involved in the vasorelaxation. Furthermore, sulforaphane inhibited thromboxane $A_2$-induced increases in pERK1/2 levels suggesting the mechanism including inhibition of thromboxane $A_2$-induced increases in ERK1/2 phosphorylation. This study provides evidence that sulforaphane induces vascular relaxation through inhibition of Rho-kinase or MEK in rat aortae.

• 약학회지
• /
• 제57권5호
• /
• pp.376-381
• /
• 2013

The present study was undertaken to investigate the influence of curcumin on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that curcumin, the primary ingredient of Curcuma longa, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, curcumin inhibited fluoride-induced contraction but didn't inhibit phorbol ester-induced contraction suggesting that additional pathways different from endothelial nitric oxide synthesis might be involved in the vasorelaxation. Furthermore, curcumin significantly inhibited fluoride-induced increases in pMYPT1 levels. On the other hand, it didn't significantly inhibit phorbol ester-induced increases in pERK1/2 levels suggesting the mechanism involving inhibition of fluoride-induced MYPT1 phosphorylation. This study provides evidence that curcumin induces vascular relaxation through inhibition of Rho-kinase in rat aortae.