非选择性内皮素受体拮抗剂波生坦对糖尿病大鼠内皮素系统的作用研究

目的：观察非选择性内皮素受体拮抗剂波生坦(Bosentan)对糖尿病大鼠内皮素系统的作用。方法：SD大鼠经链脲佐菌素诱导建立糖尿病大鼠模型，设非治疗组、Bosentan治疗组及正常对照组。4周后比较各组大鼠血浆及肾脏内皮素含量，并用RT—PCR及免疫组化法检测大鼠肾脏内皮素-1(ET-1)和内皮素A、B两种受体基因与蛋白的表达。结果：糖尿病大鼠的ET—1表达明显增加。非治疗组大鼠肾脏ET—A受体的表达显增多。而Bosentan治疗使其表达明显下降。三组大鼠肾组织ET—B受体的表达并无明显区别。结论：糖尿病大鼠肾组织中有内皮素系统的高度活跃。Bosentan不仅通过与ET-1竞争内皮素受体，而且能够下调肾组织中表达增多的ET—A受体，从而显干扰了ET-1的致病作用。     

内皮素受体拮抗剂对损伤脊髓早期保护作用

目的评价非选择性内皮素(ET)受体拮抗剂PD145065对损伤脊髓的保护作用,证实ET参与脊髓损伤(SCI)后继发损伤的假设并探讨其作用机制。方法压迫法致伤大鼠脊髓(50g,1min)。损伤前10min鞘内注射PD145065或生理盐水,观察脊髓血流(SCBF)、丙二醛(MDA)、细胞内钙(［Ca2+］i)、伊文思兰(EB)及水含量变化。结果伤区SCBF在伤后5min即有明显下降,为基线的(75.23±9.21)%,2h降为(57.06±7.35)%;伤区邻近血流下降较慢,伤后30min降为(79.82±7.98)%。伤区及邻近区伤后4h?SCBF都未恢复。伤段脊髓组织中MDA、［Ca2+］i、EB和水含量均高于假手术组(P＜0.05)。PD145065明显改善了伤区SCBF,消除了伤区邻近段SCBF的下降。PD145065预处理组脊髓中MDA、［Ca2+］i、EB和水含量均低于生理盐水组(P＜0.05)。结论PD145065对损伤脊髓早期有明显保护作用,ET及其受体可能通过多种途径参与SCI后的继发损伤。临床应用ET受体拮抗剂对SCI可能有治疗作用。     

Influence of Dialysis Membranes on Interleukin-1β and Interleukin-1 Receptor Antagonist Production by Peripheral Blood Mononuclear Cells

Abstract: We investigated the production of interleukin (1L)-1β and IL-1 receptor antagonist (Ra) by peripheral blood mononuclear cell (PBMC) in vitro during hemodialysis of 7 dialysis patients using 4 differential dialysis membranes (regenerated cellulose [RC], polyamide [PA], polysulfone [PSI and AN-69). Blood sampling was performed before dialysis (0 min), 15 min after starting dialysis, and after dialysis (240 min) during the last session of each treatment. The cellular content of fresh cells and the production of IL-1β and IL-1Ra with and without lipopolysaccharide (LPS) stimulation of the cells were evaluated and measured by enzyme-linked immunosorbent assay (ELISA). The level of IL-1β with LPS stimulation using RC, PA, and PS membranes was significantly reduced at 15 min and was not changed at 240 min as compared with the level at 0 min. On the other hand, the level of IL-1β with LPS stimulation using an AN-69 membrane at 15 and 240 min was not significantly different from that at 0 min. Neither initial cellular content nor spontaneous production of IL-1β were detected at 0, 15, or 240 min in any of the membranes. The spontaneous production of IL-1Ra at 15 and 240 min was not significantly different from that at 0 min in any of the membranes. The cellular content of IL-1Ra using the RC membrane was significantly lower at 15 min and did not differ at 240 min from the level at 0 min. The cellular content of IL-1Ra using PA, PS, and AN-69 membranes was not significantly different at 15 and 240 min from that at 0 min. However, the IL-1Ra level with LPS stimulation using RC and PA membranes was significantly reduced from that at 0 min, but the level using PS and AN-69 membranes was not different from that at 0 min. Because IL-1β and IL-1Ra levels 15 min after starting dialysis using bioincompatible dialysis membranes were reduced from the levels at 0 min, the findings suggest that measurement of cytokines during dialysis treatment at an early stage is a useful marker for evaluating the biocompatibility of a dialysis membrane.     

Genetic Determinants of Circulating Interleukin-1 Receptor Antagonist Levels and Their Association With Glycemic Traits

The proinflammatory cytokine interleukin (IL)-1β is implicated in the development of insulin resistance and β-cell dysfunction, whereas higher circulating levels of IL-1 receptor antagonist (IL-1RA), an endogenous inhibitor of IL-1β, has been suggested to improve glycemia and β-cell function in patients with type 2 diabetes. To elucidate the protective role of IL-1RA, this study aimed to identify genetic determinants of circulating IL-1RA concentration and to investigate their associations with immunological and metabolic variables related to cardiometabolic risk. In the analysis of seven discovery and four replication cohort studies, two single nucleotide polymorphisms (SNPs) were independently associated with circulating IL-1RA concentration (rs4251961 at the IL1RN locus [n = 13,955, P = 2.76 × 10⁻²¹] and rs6759676, closest gene locus IL1F10 [n = 13,994, P = 1.73 × 10⁻¹⁷]). The proportion of the variance in IL-1RA explained by both SNPs combined was 2.0%. IL-1RA–raising alleles of both SNPs were associated with lower circulating C-reactive protein concentration. The IL-1RA–raising allele of rs6759676 was also associated with lower fasting insulin levels and lower HOMA insulin resistance. In conclusion, we show that circulating IL-1RA levels are predicted by two independent SNPs at the IL1RN and IL1F10 loci and that genetically raised IL-1RA may be protective against the development of insulin resistance.     

Interleukin-1 Receptor Antagonist Enhances Islet Engraftment Without Impacting Serum Levels of Nitrite or Osteopontin

Interleukin-1β (IL-1β)-mediated early islet graft dysfunction and loss of islet mass can occur in different phylogenic types of islet transplantation. Large quantities of interleukin-1 receptor antagonist (IL-1RA) have been demonstrated to impede IL-1β-mediated adverse effects on islet grafts in allo- and xenotransplantation. To clarify the influence of IL-1RA on early function and mass change, as well as long-term hypoglycemic effects of islet isografts, we studied streptozotocin-induced diabetic C57BL/6 mice infected with replication-defective adenovirus carrying the mouse IL-1RA cDNA gene. This vector increased the mean serum level of IL-1RA to 8 ng/mL, approximately three times greater than for mice receiving adenovirus carrying the beta-galactosidase (β-Gal) gene. The blood glucose levels declined faster and the insulin content of the graft was significantly higher on day 10 following transplantation among mice receiving mIL-1RA gene than the controls. Nevertheless, the insulin content of the pancreatic remnant did not differ among mice in the IL-1RA, β-Gal, and vehicle control groups. Serum levels of nitrite and osteopontin before and 3 days after islet transplantation did not differ considerably among the IL-1RA, β-Gal, and vehicle groups. Compared with the β-Gal group, temporary posttransplantation hyperglycemia was significantly shortened in the IL-1RA group mice. Removal of graft-bearing kidneys at 13 weeks following transplantation caused recurrence of hyperglycemia in all treated diabetic mice. The insulin content of pancreatic remnants removed at 15 weeks following transplantation was similar in the IL-1RA and β-Gal groups. In conclusion, a mildly elevated serum concentration of IL-1RA protected and enhanced engraftment of islet isografts immediately after transplantation.     

缬沙坦对糖尿病大鼠肾皮质TGF-β1表达的影响

目的:探讨血管紧张素Ⅱ受体拮抗剂缬沙坦(Valsartan)对实验性糖尿病大鼠肾皮质TGF-β1表达的影响,为糖尿病肾病的防治提供实验性理论基础.方法:选择健康雄性SD大鼠24只,任取其中16只腹腔注射链脲佐菌素制成糖尿病大鼠模型.将糖尿病大鼠随机分为糖尿病缬沙坦治疗组(A组,8只,缬沙坦10 mg*kg-1*d-1灌胃);糖尿病对照组(B组,8只);其余8只为正常对照组(C组).分别于实验第6周末测定各组大鼠血糖、血肌酐、尿白蛋白排泄率,对肾脏标本进行光镜观察,用图像分析仪测量各组大鼠平均肾小球面积、平均肾小球体积.并取各组大鼠肾皮质提取RNA,用逆转录-PCR(RT-PCR)方法对肾皮质TGF-β1 mRNA表达进行半定量分析.结果:在糖尿病第6周末,B组上述指标较C组均有不同程度的升高(P＜0.01),而A组则显著低于同时期的B组.其中,A组、C组尿白蛋白排泄率始终无统计学差异,肾小球平均面积、平均体积A组显著低于B组(P＜0.01).RT-PCR半定量结果分析显示,B组TGF-β1 mRNA表达较A组、C组显著增高(P＜0.01),A组TGF-β1 mRNA表达较C组为高(P＜0.01),但仍较B组为低(P＜0.05).结论:缬沙坦能够抑制肾组织TGF-β1 mRNA的表达,减少糖尿病大鼠的尿白蛋白,减轻及延缓肾小球硬化,发挥保护肾脏的作用.     

Biomechanical Evaluation of Acellular Collagen Matrix Augmented Achilles Tendon Repair in Sheep

The rate of rerupture of repaired Achilles tendon in young and athletic populations remains high despite improvement in surgical techniques, suture design, and postsurgical management. Acellular biological matrices can be used to enhance the immediate strength of repaired tendons and to serve as scaffolds for cell in-growth and constructive tissue remodeling. A number of commercially available matrices have been used clinically, albeit with varying degrees of success and failure. The disparity is likely attributable to the different physical and biochemical properties of individual matrices. In this study, we investigated the biomechanical characteristics of 2 different acellular collagen matrices, namely TissueMend^® and GraftJacket^®, using a sheep Achilles tendon repair model. Static and cyclic creep, cyclic and linear construct stiffness, maximum load to failure, and displacement at maximum load were determined at time zero. We found that the maximum load to failure, displacement, and ultimate failure mode were similar between tendons augmented with either acellular collagen matrix; however, TissueMend augmentation yielded lower creep and smaller construct elongation than did GraftJacket. The results indicated that the strength of TissueMend-augmented tendons and GraftJacket-augmented tendons was not statistically significantly different, although tendons augmented with TissueMend displayed greater stiffness, which may be clinically advantageous in the restoration of ruptured tendons.     

Estimation of Total Collagen and Types I and III Collagen in Canine Rotator Cuff Tendons

The collagen composition of the supraspinatus, infraspinatus, and subscapularis tendons, which form part of the rotator cuff of the shoulder, was determined. Tendons were obtained from adult, male beagle dogs and total collagen was estimated by measurement of hydroxyproline. There was little variation in collagen content among the three major cuff tendons and the quantity approximated that cited in the literature for other tendons. However, the collagen content in the insertion zone of the supraspinatus tendon was significantly higher than in the tendon proper. NaCl fractionation of supraspinatus collagen indicated that type I was the predominant collagen but significant amounts of type III and possibly some type II and type V were also present. Interestingly, there appeared to be more type III collagen in the insertion zone than in the tendon proper, cyanogen bromide digestion and peptide mapping confirmed this finding. The differential collagen composition of the supraspinatus tendon may contribute to the high incidence of tear that is associated with this rotator cuff tendon. Received: 10 May 1996 / Accepted: 23 April 1997     

A Pilot Study: The Therapeutic Effect of Ultrasound following Partial Rupture of Achilles Tendons in Male Rats

The purpose of this pilot study was to determine whether ultrasound administered in clinical dosage has a therapeutic effect on the healing of partially ruptured Achilles tendons. The subjects were 11 young male Marland rats which were divided into two main groups. One group was treated for 2 weeks, the other for 3. Each group consisted of experimental and control animals, the control animals being mock-sonated only. A day after the final treatment the tensile strength of the Achilles tendon of all the rats was assessed. In addition, a light microscope and an electron microscope analysis of Achilles tendon tissue from rats on the 3 week treatment program was done. The statistical analysis of the data indicated a significant difference only between the experimental and control animals in the group sonated for 3 weeks. Electron microscope analysis showed ultrastructural changes in the tissue of the experimental animal consonant with those changes that would be found in a more advanced stage of the healing process.J Orthop Sports Phys Ther 1988;10(2):39-46.     

Effects of Oxytetracycline on Solubility and Synthesis of Collagen in Young Rats

In a recent study we demonstrated that the antibiotic oxytetracycline reduces both growth and mechanical strength of bone and skin in young rats. the present study deals with the effects of 14 days of oxytetracycline medication on salt solubility of collagen (cross-linking) and conversion of ¹⁴C-proline to ¹⁴C-hydroxyproline in collagen (synthesis). At the end of the medication period, significantly higher solubility of collagen was found in the femurs and skin of rats receiving oxytetracycline than in controls. No effect of the antibiotic on the rate of collagen synthesis could be demonstrated. These findings may indicate that oxytetracycline in young rats causes reduced mechanical strength of bone and skin by interfering with the cross-linking of collagen.     

Effects of Oxytetracycline on Solubility and Synthesis of Collagen in Young Rats

In a recent study we demonstrated that the antibiotic oxytetracycline reduces both growth and mechanical strength of bone and skin in young rats. the present study deals with the effects of 14 days of oxytetracycline medication on salt solubility of collagen (cross-linking) and conversion of ¹⁴C-proline to ¹⁴C-hydroxyproline in collagen (synthesis). At the end of the medication period, significantly higher solubility of collagen was found in the femurs and skin of rats receiving oxytetracycline than in controls. No effect of the antibiotic on the rate of collagen synthesis could be demonstrated. These findings may indicate that oxytetracycline in young rats causes reduced mechanical strength of bone and skin by interfering with the cross-linking of collagen.     

Effects of Salmon Calcitonin on Synthesis and Mineralization of Collagen in Rats

The effects of salmon calcitonin (CT) on collagen metabolism and mineral deposition in fractures and intact femora, and on collagen metabolism in healing skin wounds and intact skin have been studied in young male rats. Serum calcium and serum phosphorus were reduced 3 h after the daily subcutaneous CT injection (3 MRC-U/kg body weight), whereas a rebound increase in the serum levels of both minerals was observed at 24 hours after the injection.

CT had an early transient inhibitory influence on the collagen synthesis, and this resulted in a reduced total content of collagen in bones and skin specimens from treated rats compared to controls. the concentration of collagen in bone and skin was, however, increased in treated animals compared to controls after prolonged CT administration.     

肾疏宁对MsPGN大鼠肾小球系膜基质的影响

目的 :观察肾疏宁对MsPGN大鼠肾小球系膜基质中ColⅣ、FN的影响。方法 :综合运用口服牛血清白蛋白 ,尾静脉注射葡萄球菌肠毒素 ,定期注射弗氏佐剂 ,复制了大鼠MsPGN模型 ,利用免疫组化观察肾疏宁对MsPGN大鼠肾小球系膜基质中ColⅣ、FN的影响。结果 :模型组系膜基质中ColⅣ、FN表达明显增多 ,肾疏宁组和肾炎康复片组的表达则明显减少 ,其中肾疏宁组尤为显著。结论 :肾疏宁可能通过减少肾小球系膜区的FN及ColⅣ的表达而达到治疗MsPGN的目的     

The High-Affinity Estrogen Receptor Antagonist ICI 182,780 Has No Effect on Bone Growth in Young Male Rats

Estrogens have profound effects on the processes of bone formation and turnover in females. The physiological role of this class of hormones on bone metabolism in males is less certain. The purpose of this study was to determine the effect of the high affinity estrogen receptor antagonist ICI 182,780 on tibial growth in normal male rats. The effects of ICI 182,780 on growing male rats were compared to orchiectomy, which prevents the synthesis of estrogens as well as androgens. Neither orchiectomy nor ICI 182,780 had an effect on body weight gained. Orchiectomy decreased longitudinal bone growth at the proximal tibial metaphysis and radial bone growth at the tibia-fibula synostosis. In contrast, ICI 182,780 had no effect on either endochondral or intramembranous bone growth. These findings suggest that androgens are more important than estrogens in determining peak bone mass in male rats. Received: 11 May 1999 / Accepted: 11 January 2000     

基质金属蛋白酶及其抑制物与子宫内膜异位症的研究进展

子宫内膜异位症是妇科的常见疾病,其发病机制至今未明。近年来研究发现,基质金属蛋白酶（MMPs）及其抑制物（TIMPs）在该病的发生及发展中起了重要作用,现就MMPs及其抑制物TIMPs在子宫内膜异位症中的研究进展做一综述。