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1.
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The prophylactic and therapeutic effects of gold sodium thiomalate, cyclosporin A, cyclophosphamide, and placebo on collagen-induced arthritis (CIA) were evaluated in DA rats. Prophylactic treatment with cyclosporin A and cyclophosphamide suppressed the arthritis incidence, clinical inflammation, destructive bone changes, and development of anti-collagen antibody in DA rats subsequently injected with porcine type-II collagen. Therapeutic treatment with cyclosporin A and cyclophosphamide had a definite suppression on established CIA when started 21 days after the initial collagen injection, but the suppression was less marked than that of prophylactic treatment. Gold had no impact on CIA in DA rats when administered either prophylactically or therapeutically.  相似文献   

3.
The long term effects of indomethacin, cyclosporin, cyclophosphamide, and placebo on collagen-induced arthritis in mice were tested under two different treatment protocols. A prophylactic experiment examined the effects of the daily drug administration for 180 days beginning one day before the first collagen injection. Under this dosage schedule, cyclophosphamide and cyclosporin decreased the severity of arthritis, while indomethacin did not. A therapeutic protocol examined the effects of these same drugs when daily administration was delayed until the animals had active disease at 78 days after the first collagen injection. Under this protocol, all three drugs reduced the progression of disease. In both protocols, the most significant suppression of arthritis was seen in animals receiving cyclophosphamide which was associated with a decrease in anti-collagen antibody levels. Collagen-induced arthritis in mice should be further investigated as a model to study the long term effects of slow-acting anti-rheumatic drugs.Supported in part by a grant from Pennwalt Pharmaceutical Company, Rochester, NY, the Veterans Administration Medical Research program, Nora Eccles Treadwell Foundation, and grants from the National Institutes of Health AR-02255 and AM30763.  相似文献   

4.
The effect of N-methyl-N-nitrosourea (MNU), sodium saccharin, sodium cyclamate and cyclophosphamide on rat bladder explants in vitro was studied. MNU administered as a single dose or in multiple treatments induced concentration-dependent changes in urothelial ultrastructure and cell surface topography. In a single treatment protocol, extensive cytotoxicity was observed in both the urothelium and stroma at concentrations of 500 to 1000 micrograms/ml, establishing a toxic threshold within this range. In a multiple treatment protocol, repeated doses of low concentrations of carcinogen (7 or 8 x 50 micrograms/ml, 6 x 100 micrograms/ml) induced hyperplastic and dysplastic changes in the urothelium with no cytotoxicity, but cytotoxic effects were observed following treatments of 4 x 200 micrograms/ml or 2 x 400 micrograms/ml. Sodium saccharin, sodium cyclamate, and cyclophosphamide induced changes in urothelial cell surface topography consistent with hyperplasia and preneoplasia. Prolonged exposure to saccharin or cyclamate followed by a single dose of MNU elicited more extensive abnormalities in the urothelium than either saccharin or cyclamate alone, suggesting that these artificial sweeteners have initiating activity in a multistage process. The ultrastructural changes induced by in vitro treatment showed a good correlation with the pathological changes observed in vivo in rats treated with MNU or fed either with saccharin or cyclamate.  相似文献   

5.
Prenatal exposure to alcohol feminizes saccharin consumption patterns in adult male rats. To study the involvement of testosterone in this effect, testosterone propionate (TP) was administered to pregnant dams in an attempt to reverse that feminized saccharin consumption pattern in the male offspring. Female offspring were also studied to determine the effect of TP on saccharin preference in normal males and females. During the last week of gestation, dams were administered a liquid diet containing 35% ethanol derived calories, an isocaloric liquid diet containing no ethanol, or Purina Lab Chow. Half of the dams in each group received twice daily injections of TP, the other half were injected with the oil vehicle. Saccharin consumption of adult fetal alcohol exposed (FAE) males from dams administered oil or TP was significantly greater than controls, indicating that the feminized pattern of saccharin consumption of FAE males cannot be overcome with TP administration during the prenatal period. In controls, prenatal TP exposure alone was found to increase adult saccharin consumption in both sexes. Prenatal administration of TP was also found to markedly depress body weight of offspring of dams receiving the liquid diets compared to offspring from dams receiving the same diets plus oil injections. Body weights of offspring from TP or oil injected dams receiving the chow fed diets during pregnancy did not differ.  相似文献   

6.
目的:探讨口服Ⅱ型胶原蛋白(cⅡ)对派[伊尔]氏集结(PP结)的形态学、细胞因子表达水平和血清特异性IgG、IgA、IgM含量的影响.方法:连续10 d给小鼠口服不同剂量的CⅡ,第11天和第21天用佐剂或CⅡ进行免疫,分别于第11天、第21天和第31天采集血液和PP结.PP结经HE染色后,镜下观察其增生的情况.用荧光实时定量RT-PCR法,检测PP结中IL-17、TNF-α、IFN-γ和TGF-β1 mRNA 的水平.采用ELISA法检测血清抗CⅡIgG、IgA、IgM的水平.结果:口服CⅡ10 d后,PP结增生活跃,高剂量组可见清晰的帽状结构;血清中出现IgA,未见IgG和IgM水平增加;IL-17、TNF-α、IFN-γ mRNA的表达受到抑制.以CⅡ初次免疫后,实验组IgA、IgM、IL-17的水平均低于对照组(P<0.05或P<0.01),TGF-β1的水平显著增加(P<0.05).以C Ⅱ加强免疫后,高剂量组IgA的水平显著增加(P<0.05),实验组IgM的水平仍受到抑制(P<0.05或P<0.01),TGF-β1的水平高于对照组(P<0.05).以佐剂免疫时PP结中细胞因子的表达与CⅡ免疫时相似,未见血清抗CⅡ IgG、IgA、IgM 水平的变化.结论:口服CⅡ能使血清中产生特异性IgA,抑制PP结IL-17、TNF-α、IFN-γ的基因表达,对CⅡ免疫后IgA、IgM的产生和IL-17 mRNA的表达具有一定的抑制作用.以上结果表明,血清特异性抗体的水平和细胞因子表达的变化在口服CⅡ诱导免疫耐受对类风湿性关节炎的治疗作用方面发挥着重要的作用.  相似文献   

7.
Following intranasal infection with murine cytomegalovirus (MCMV), the levels of viral replication in the lungs of susceptible BALB/c mice were enhanced by treatment with cyclophosphamide (CY), or to a greater extent cyclosporin A (CsA) or the Nu/Nu genotype. Focal inflammation was seen 2-4 days after infection in all groups. This was followed by diffuse interstitial pneumonitis which cleared 12-20 days later in the absence of immunosuppression. Although the initial foci of inflammation were less prominent in infected mice treated with CY or CsA, the most severe interstitial pneumonitis was seen 7 days p.i. in mice given CY, whilst CsA-treatment produced focal and disseminated pneumonitis 7-14 days p.i. and Nu/Nu mice exhibited only the focal response. MCMV-infected mice maintained from weaning on a low protein (4% casein) diet also retained higher titres of virus in their lungs than did normally-fed controls, and displayed more prominent focal pneumonitis.  相似文献   

8.
Properties of macrophages isolated from Peyer's patches were compared with properties of peritoneal macrophages. We found a very low expression of all types of Fc receptors as well as a low expression of Ia antigens on Peyer's patch macrophages. No substantial changes in the levels of FcR and Ia antigen expression were found during the process of ageing. The investigation of phagocytic activity showed the activated state of Peyer's patch macrophages. Comparing the surface markers of lymphocytes obtained from Peyer's patches of mice of different ages, we found no differences in the numbers of sIg+, Thy-+ or L3T4+ lymphocytes. The numbers of FcR+ and Lyt 2.2+ lymphocytes decreased markedly with age.  相似文献   

9.
Prenatal stress alters the endocrine as well as the behavioral responses of rodents. Because of the reductions in both estradiol-induced and ether-induced prolactin (Prl) release reported in prenatally-stressed (P-S) rats, we were interested in whether prenatal stress might also modify the prolactin response of male and female rats to a moderate stressor in adulthood, viz., restraint stress. Timed-mated Sprague-Dawley females were exposed to a daily regimen of heat and restraint stress from days 15-22 of gestation. Control animals remained undisturbed throughout pregnancy. In adulthood, half of the male and female P-S and Control offspring were stressed by placing them in a Plexiglas restraint tube for 60 min (restraint stressed; S; referred to as P-SS and CS, respectively). The remaining half of the P-S and Control animals were left undisturbed (these were nonrestrained; NR; referred to as P-SNR and CNR, respectively). Blood samples (decapitation) were then collected from all animals and plasma was assayed for Prl content. P-SNR and CNR males did not differ in baseline Prl levels, nor did P-SNR and CNR females. Following the restraint stress in adulthood, P-SS males as well as PSS females exhibited significantly less of an increase in Prl relative to CS males and CS females, respectively. In addition, baseline Prl levels differed between the sexes, with females--regardless of prenatal condition--having higher plasma Prl levels than males. These sex differences were no longer evident following restraint stress. These data, in combination with other work in P-S animals in the areas of Prl release and stress responses, demonstrate that prenatal stress renders the rat less hormonally (Prl) responsive to stress, with the effect being more pronounced in the female.  相似文献   

10.
The circulatory patterns in three lymphoid tissues were compared macro- and microscopically. Indian ink or a viscous silicone rubber compound were used as contrast materials and serial 75 micronm sections examined. The findings were checked with the benzidine stain for red blood corpuscles in uninjected tissues. Thymic lobules showed a "through circulation"--capillaries penetrating the cortex from within outwards and draining into surface veins, comparable with the circulation in liver lobules. By contrast, lymph nodes and Peyer's patches showed a looped capillary distribution. The outer thymic cortex and primary follicles in lymph nodes contained the maximum capillary density, correlating with the highest mitotic index of thymocytes and lymphocytes in the respective tissues. The lowest vascular density in the thymus was in the medulla, particularly in Hassall's corpuscles, in secondary follicles of lympho nodes and Peyer's patches, which correlates with the storage capacity of antigens and antibodies at those sites. Postcapillary venules in lymph nodes and Peyer's patches showed a characteristic pattern with Indian ink. These venules were absent from the thymus.  相似文献   

11.
Depression and pathological anxiety disorders are among the most prevalent neurological diseases in the world and can be precipitated and exacerbated by stress. Prenatal stress alters both behavioral and endocrine responses to stressful stimuli in later life. We have previously observed increased basal acoustic startle response (ASR) in Wistar rats exposed to stress or dexamethasone (DEX) in utero when tested during the light phase of the circadian rhythm, and decreased prepulse inhibition (PPI) in similar animals tested during the dark phase of the cycle. We speculated that this observation of increased basal startle might be influenced by diurnal phase. In the present study, adult female Sprague Dawley rats, stressed prenatally with DEX (200 μg/kg, gestational days 14-21) and postnatally by blood sampling under restraint, were tested for the ASR during both circadian phases (light and dark). Basal startle was increased in animals tested both during the light and the dark phases of the cycle. We hereby replicated our earlier findings in a new strain and laboratory, thus strengthening the validity of our model regarding prenatal stress effects on ASR in female offspring. Our results indicate that observation of increased basal ASR is not solely dependent on diurnal phase. We found no difference in hippocampal glucocorticoid and mineralcorticoid receptor expression between groups.  相似文献   

12.
A method is described for the in vivo surgical removal of all Peyer's patches from the small intestine and caecum of the rat. Over two postoperative months, this procedure had no apparent morphological effects on the small intestine or intraepithelial lymphocyte numbers, nor were the numbers of IgA producing cells in the small intestine or serum immunoglobulin levels permanently influenced. However, circulating specific antibody to human serum albumin was significantly elevated in animals without Peyer's patches 3 weeks after surgery, in comparison with a sham operated group of animals. Subsequent intestinal immunization in animals without Peyer's patches with a lipid-conjugated human serum albumin resulted in a diminished primary but a comparatively normal secondary systemic antibody response to this antigen.  相似文献   

13.
The effects of Peyer's patch (PP) inactivation on local and systemic immune response in rats was investigated. A cauterization method has been developed to inactivate PP. Animals were primed intraperitoneally or intragastrically with trinitrophenyl-keyhole limpet haemocyanin (TNP-KLH) one day before cauterization, and were challenged intraintestinally two weeks later. The secondary immune response in the spleen, mesenteric lymph node (MLN) and intestinal villi was studied by immunohistochemistry. Histological observations on PP after inactivation showed that most T cells in the interfollicular area had disappeared, as had B cells in the follicle. T cells repopulated PP much slower than B cells. Complete recovery of PP occurred no earlier than 2 weeks after inactivation. The immunization experiments revealed higher numbers of anti-TNP antibody-forming cells (anti-TNP AFC) of IgM, IgG and IgA isotypes in the spleen of the PP-inactivated animals than in the controls. Very few anti-TNP AFC were found locally in the lamina propria of the intestinal villi or in the MLN in both groups. It is suggested that PP play a role in the regulation of systemic immune responses against intestinally-administered thymus-dependent antigen. Moreover, inactivation of PP could alter the antigen uptake by gut epithelium and the local antigen processing. As a result, an increased amount of antigen could reach the spleen eliciting a higher immune response.  相似文献   

14.
The aim of this immunohistologic study was to determine how lymphocytes and accessory cells associated with antigen processing are distributed in the domes of Peyer's patches. Monoclonal antibodies against mouse B cells (anti-B220), T cells (anti-Thy-1.2), T helper cells (anti-L3T4), T cytotoxic/suppressor cells (anti-Lyt-2), macrophages (anti-Mac-1), and Ia+ cells (anti-I-Ad) were applied to cryostat sections of mouse Peyer's patches and visualized with peroxidase-conjugated avidin-biotin complexes (ABC). The subepithelial dome, the dome epithelium, and the follicle crypt epithelium were ech surveyed for cells labeled with these antibodies. Each region had a characteristic and nonrandom distribution of labeled cells. In the subepithelial dome, B cells, T helper cells, macrophages, and Ia+ accessory cells formed a cellular meshwork between follicle and the dome epithelium. T cytotoxic/suppressor cells were sparse beneath the epithelium. In the dome epithelium, solitary and paired lymphocytes occurred both above and below the level of epithelial cell nuclei. B cells predominated, and both T helper cells and T cytotoxic/suppressor cells were present. B cells sometimes aggregated in small clusters. Macrophages were rarely observed in the epithelium. The distribution of cells in the dome epithelium was distinctly different from non-Peyer's patch intestine where T cytotoxic/suppressor cells predominated and B cells were few in number. Although lymphocytes were usually absent in crypts outside Peyer's patches, in follicle crypts B cells and T cells were seen but not Ia+ accessory cells or macrophages. Most of the T cells in the crypt epithelium were T cytotoxic/suppressor cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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16.
The effect of antigen on the development of Peyer's patches in sheep   总被引:2,自引:0,他引:2  
The proposition that the development of Peyer's patches (PP) is influenced by antigenic stimulation has been examined in sheep. Terminal lengths of ileum containing about half of the ileocecal PP were isolated from the intestinal tracts of fetal lambs during the last month before birth. Antigen was injected into some of these segments and the subsequent development of the PP studied before and after birth. The injection of either killed B. abortus, ferritin or maternal colostrum into the lumens of the isolated ileal segments did not cause premature growth of the PP follicles, nor did it effect the content of lymphoblasts in them. In contrast, the injection of these antigens into the isolated segments caused the development of germinal centers and plasma cells in the regional mesenteric lymph nodes. Plasma cells also appeared in the lamina propria along the intestinal tract in response to these antigens. These results provided experimental evidence that lymphopoiesis in the follicles of the PP of fetal lambs is not dependent on antigen. The PP in ileal segments that were not injected with antigen and had no contact with antigen subsequently grew at the normal rate before and for the first 2 weeks after birth; after this the growth of the follicles became significantly slower than normal. The follicles in these isolated ileal segments had almost completely disappeared by 3-4 months of age, whereas the follicles in the normal functional ileum did not undergo involution until around 15 months of age. The premature involution in the PP in the isolated segments was prevented by reconnecting the segment to the functional intestinal tract before 3 months of age.  相似文献   

17.
目的:探索乳杆菌免疫作用机制.方法:BALB/c小鼠灌胃乳杆菌,从小鼠空肠派伊尔结提取RNA,基因芯片分析基因表达情况,基于已知的基因网络数据库利用Onto-Tools分析乳杆菌刺激引起的特异性基因网络.结果:Onto-Tools分析得到的通路中,涉及到免疫的通路有T细胞受体信号通路、B细胞受体信号通路、细胞因子和细胞因子受体通路、抗原加工和呈递等;涉及到粘膜屏障的有粘着斑、粘着连接、紧密连接和细胞粘附分子;还有涉及到细胞周期和凋亡的通路;其中通路中影响因子最高的为MAPK信号通路和粘着斑.结论:乳杆菌刺激引起大量蛋白表达,激活粘膜屏障,引起T细胞受体信号通路、B细胞受体信号通路、细胞因子和细胞因子受体通路等通路,从而造成免疫应答.  相似文献   

18.
Compromised fetal growth impairs vascular function; however, it is unclear whether chronic hypoxia in utero affects adult endothelial function. We hypothesized that maternal hypoxia (H, 12% O2, n = 9) or nutrient restriction (NR, 40% of control, n = 7) imposed from day 15–21 pregnancy in rats would impair endothelial function in adult male offspring (relative to control, C, n = 10). Using a wire myograph, endothelium-dependent relaxation in response to methacholine was assessed in small mesenteric arteries from 4- and 7-month-old (mo) male offspring. Nitric oxide (NO) mediation of endothelium-dependent relaxation was evaluated using N ω-nitro- l -arginine methyl ester ( l -NAME; NO synthase inhibitor). Observed differences in the NO pathway at 7 months were investigated using exogenous superoxide dismutase (SOD) to reduce NO scavenging, and sodium nitroprusside (SNP; NO donor) to assess smooth muscle sensitivity to NO. Sensitivity to methacholine-induced endothelium-dependent relaxation was reduced in H offspring at 4 months ( P < 0.05), but was not different among groups at 7 months. l -NAME reduced methacholine sensitivity in C ( P < 0.01), H ( P < 0.01) and NR ( P < 0.05) offspring at 4 months, but at 7 months l -NAME reduced sensitivity in C ( P < 0.05), tended to in NR ( P = 0.055) but had no effect in H offspring. SOD did not alter sensitivity to methacholine in C, but increased sensitivity in H offspring ( P < 0.01). SNP responses did not differ among groups. In summary, prenatal hypoxia, but not nutrient restriction impaired endothelium-dependent relaxation at 4 months, and reduced NO mediation of endothelial function at 7 months, in part through reduced NO bio-availability. Distinct effects following reduced maternal oxygen versus nutrition suggest that decreased oxygen supply during fetal life may specifically impact adult vascular function.  相似文献   

19.
Neonatal inhibition of the renin-angiotensin system [angiotensin-converting enzyme (ACE) inhibition] in the rat results in long-term abnormal renal morphology and function, including interstitial inflammation and fibrosis. Hyaluronan (hyaluronic acid, HA) has pathological implications in inflammatory diseases and renal ischaemia-reperfusion injury. The present study aimed at determining if renal cortical HA in the adult rat is correlated to the abnormal morphology and function in rats treated neonatally with the ACE inhibitor enalapril. In adult control rats (23 weeks old), the cortical HA content was very low [about 5 microg g(-1) dry weight (d.w.)] and about 1% of the papillary HA content. In rats treated neonatally with enalapril (days 3-13), the cortical HA level was 15 times that in control rats already at 21 days after birth, and it persisted at this level during adulthood (at 23 weeks). At 13 weeks the enalapril-treated animals showed markedly reduced ability (-53%) to concentrate urine during 24-h thirst provocation. At 21 days as well as at 23 weeks the enalapril-treated kidneys displayed morphological changes, such as papillary atrophy, dilation of the tubules and cellular infiltration of the cortical tissue. Histochemical staining confirmed the HA quantification assay and revealed a patchy staining for HA located in the same regions as the infiltrating cells. In conclusion, neonatal treatment with the ACE inhibitor enalapril results in renal morphological and functional abnormalities during adulthood. Cortical HA levels are already seriously elevated at day 21 and coexist with infiltrating cells. Besides the known effects of angiotensin II in development, the accumulation of HA in these kidneys may be involved in the genesis of at least the cortical abnormalities in enalapril-treated animals because of the proinflammatory effects and water-binding properties of HA.  相似文献   

20.
The Peyer's patches (PP) of sheep have a number of important anatomical features and functional characteristics which are similar to tissues that have been classified as primary lymphoid organs. The prenatal maturation of PP occurs in the absence of any antigenic stimulus as immunogenic molecules are not normally encountered by the sheep fetus. Primordial PP were first detected in the small intestine of fetal sheep at about 60-days gestation; lymphoid follicles were present by 75-days gestation and vigorous lymphopoiesis was occurring in these follicles by 100 days. From 120-days gestation until birth, at about 150 days, the PP follicles were histologically mature and they had the greatest density of proliferating lymphoid cells found anywhere in the body. The total number of PP and their constituent follicles had developed before birth when there were 25-40 discrete PP in the jejunum and proximal ileum and one single continuous PP in the terminal ileum. There was no evidence of any change in the rate of growth of the PP follicles at birth which could be related to the advent of the first antigens in the gut. The total weight of PP tissue was greater than any other single lymphoid tissue by about 6 weeks after birth weighing around 120 g or about 1.2% of the body weight; about 50-60 g of the PP tissue was calculated to be lymphoid tissue. At this time the ileocecal PP (IPP) extended 2.5 m along the terminal ileum and accounted for about 90% of the total mass of PP. From about 12 weeks after birth the IPP began to involute and only a few PP follicles remained in this region of the intestine by 18 months of age. Follicles in PP in other parts of the small intestine remained and continued to produce lymphocytes throughout the life of the animal. PP contain a number of anatomically and functionally distinct lymphoid compartments that could play different roles in the body's immune defense. Explicit in most theories on the function of PP is the notion that antigenic stimulation is the cause of the lymphopoiesis in the follicles; our results do not support this view. Instead they suggest that the follicles in the PP of sheep may play a role similar to that played by the bursa of Fabricius in birds.  相似文献   

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