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1.
为探讨催乳素在大鼠不同时期乳腺及血液中的变化规律,选择雌性SD大鼠42只,分别为处女鼠、妊娠鼠(6 d、12 d、18 d)、泌乳鼠(6 d、12 d、18 d),每个时期6只.在指定的时间点处死大鼠取乳腺组织及血清.用放免法对催乳素表达的变化进行定量研究,用统计学方法进行处理,观察催乳素的变化规律.结果显示,血清PRL水平以处女期最高,妊娠开始急剧下降,随着妊娠进行又逐渐增加,分娩后随着泌乳进行期渐渐下降.处女期与其余各期差异显著(P<0.05),整个妊娠期间以妊娠18 d为最高,且妊娠期间差异不显著(P>0.05),泌乳6 d明显高于泌乳12 d、18 d(P<0.05),泌乳12 d、18 d明显低于妊娠各期水平(P<0.05).乳腺PRL变化模式与血清的变化不一致,处女期最高,随妊娠下降,泌乳期相对稳定,变化不大.处女期与其余各期差异显著(P<0.05),妊娠6 d水平仅明显低于处女期(P<0.05),而显著高于其余各期(P<0.05).表明催乳素不仅参与了乳腺细胞的发育,而且在维持和启动泌乳方面也起到重要的作用.  相似文献   

2.
为探讨大鼠血液中雌激素、孕激素的变化规律,试验选择雌性SD大鼠42只,分别为处女鼠(0~90 d,第90 d开始交配)、妊娠鼠(96 d、102 d、108 d)、泌乳鼠(114 d、120 d、126d),每个时期6只.在指定时间点处死大鼠取血液,用放射免疫法(RIA)对雌激素、孕激素进行定量研究,观察雌激素、孕激素...  相似文献   

3.
通过研究天然植物提取物芦丁对大鼠泌乳性能、内分泌激素、脏器指数的影响,考察芦丁调节大鼠泌乳的效果.试验选择18只Wistar受孕母鼠,随机分为3组,每组6只,分别为对照组、芦丁组(每日灌服芦丁60 mg/kg BW)、雌二醇组(每周肌肉注射雌二醇60 μg/kg BW),从哺乳第4天开始连续给药2周,基础饲粮相同.测定指标包括:大鼠泌乳量,仔鼠平均体增重,乳腺器官指数,胸腺指数,脾脏指数,血浆与乳腺组织中雌激素(E2)、孕激素(P)、催乳素(PRL)、生长激素(GH)的含量.试验结果显示:芦丁组大鼠泌乳量显著高于对照组(P<0.05),与雌二醇组差异不显著(P>0.05);仔鼠体增重芦丁组与雌二醇组差异不显著(P>0.05),但显著大于对照组(P<0.05);大鼠血浆与乳腺组织中E2、PRL、GH的水平,芦丁组显著高于对照组(P<0.05),低于雌二醇组(P<0.05),P水平各组间差异不显著(P>0.05);大鼠乳腺、胸腺、脾脏器官指数雌二醇组显著高于芦丁组和对照组(P<0.05).由此得出,芦丁能够显著提高大鼠泌乳量,促进大鼠胸腺、脾脏等器官的发育.  相似文献   

4.
本试验旨在研究饲粮添加精氨酸(Arg)对娩后Wistar大鼠乳腺组织发育及其酪蛋白合成的影响。采用同窝对照的方法,选择同窝12只已受孕的Wistar大鼠,随机平均分为2组。Arg组在基础饲粮中添加与其等量的Arg(饲粮Arg含量1.280%),对照组饲粮用谷氨酸替代Arg组中的Arg以平衡饲粮氮水平。预试期4 d(分娩前4天)和正试期17 d(分娩后17天),结束后采集泌乳大鼠的乳腺组织,制作组织切片并测定其酪蛋白含量。结果表明:Arg能促进乳腺组织的发育,且乳腺腺泡切面面积的极显著增大(P0.01)。另外,Arg对乳腺β-酪蛋白的含量有显著的提高作用(P0.05),同时娩后大鼠体重也有增加的趋势(P0.05)。结果提示,饲粮添加Arg对Wistar大鼠乳腺组织发育及β-酪蛋白的合成有显著的促进作用。  相似文献   

5.
此试验旨在研究褪黑素膜受体(Melatonin membrane receptors, MT)在奶山羊乳腺中的分布和表达及褪黑素对奶山羊乳腺β-酪蛋白(β-casein)表达的调节作用。以泌乳期奶山羊为研究对象,采用Real-time PCR和免疫组织化学染色方法检测MT1和MT2在泌乳期不同阶段奶山羊乳腺中的表达和分布;褪黑素处理体外培养的泌乳期乳腺组织,Real-time PCR方法检测其β-酪蛋白mRNA的表达情况。结果发现:(1)MT1和MT2 mRNA在泌乳期奶山羊乳腺都有表达,并具有相同的表达趋势,泌乳高峰期(泌乳期60 d)显著高于泌乳上升期(泌乳期30 d)和泌乳下降期(泌乳期120 d)(P0.05);(2)MT1和MT2主要定位于乳腺上皮细胞,泌乳高峰期为强阳性,泌乳上升期和下降期阳性反应较弱;(3)褪黑素处理能显著下调乳腺组织β-酪蛋白mRNA的表达(P0.05)。结果表明,褪黑素能直接作用于乳腺,调节泌乳期奶山羊泌乳活动。  相似文献   

6.
利用外源激素短处理技术,对青年期转基因山羊(10~12月龄)进行人工诱导泌乳,并分析外源激素的处理对转基因山羊乳房发育、泌乳规律、乳汁成分、身体健康的影响,评估此技术对青年转基因山羊进行人工诱导泌乳的可行性.试验组A:8只转基因母羊联合注射雌激素和孕酮(E2∶P4按1∶8)配以利血平进行人工诱导泌乳;试验组B:另7只转基因母羊采用E2∶P4按1∶3进行人工诱导泌乳;并且选择同龄的10只普通母山羊作为对照组C,人工诱导泌乳方案同试验组A;选择同龄的10只普通母山羊作为对照组D,人工诱导泌乳方案同试验组B.结果表明:①转基因山羊经高比例的雌激素水平(E2∶P4=1∶3)的诱导作用,乳腺发育充分,乳房饱满且内部充盈乳汁,乳房容积率是低雌激素水平组羊(E2∶P4=1∶8)的2倍;②最初1周,经高比例的雌激素水平诱导的转基因山羊产奶量是低比例的雌激素水平组的2倍,差异极显著(182 mL/d±25 mL/d vs 93 mL/d±12 mL/d,P<0.01);③转基因山羊经激素诱导泌乳,在最初1周内乳汁分泌量呈先下降后逐步上升的变化规律;④通过人工激素诱导转基因山羊产生的乳汁,乳糖含量为4.35%~4.66 %,乳脂含量3.71%~4.16%,蛋白质含量4.06%~4.11%,均与对照组乳汁无显著差异;⑤诱导泌乳,对山羊自身的健康无显著影响,试验后,能够恢复情期并产羔.可见外源激素人工诱导泌乳短处理技术在青年转基因山羊上应用是可行的.  相似文献   

7.
为了观察补气活血中药(川芎、黄芪)对大肠杆菌内毒素(1.0 g/kg)致妊娠高血压综合征大鼠血压、尿蛋白及胎盘、胎仔发育情况的影响,试验分别取不同受试组进行对比,即将雌雄鼠合笼,次日早晨找到阴道脱落栓即被认定为怀孕0 d(E0 d),按顺序依次分入各受试组,即正常妊娠组(A组)、妊娠高血压综合征模型对照组(B组)、硫酸镁阳性对照组(C组)、川芎、黄芪组(D组)。大鼠单笼饲养,4组大鼠从妊娠第10天起每隔2 d测血压及24 h尿蛋白,于妊娠第20天乙醚麻醉后处死动物,并取胎盘组织及观察胎仔情况。结果表明:与A组相比,B组尿蛋白、血压水平显著升高(P0.05),说明造模成功。与D组相比,B组尿蛋白、血压均显著降低(P0.05)。与C组相比,B组血压显著升高(P0.05),使尿蛋白略有下降。D组死胎率与B组相比明显降低,畸胎率亦显著降低(P0.05)。川芎、黄芪能够有效降低妊娠高血压综合征大鼠血压、尿蛋白,促进妊娠高血压综合征大鼠胎盘供血和胚胎发育。  相似文献   

8.
为了揭示建昌黑山羊主要生殖激素在繁殖期不同阶段的分泌规律,试验选择12头建昌黑山羊健康母羊,分别于妊娠早期(妊娠1~90 d)、妊娠晚期(妊娠91~150 d)、泌乳期和空怀期采集血样,分离血清后采用酶联免疫法(ELISA)进行检测,根据标准回归方程得到繁殖期内各阶段雌二醇(E2)、孕酮(P4)、促卵泡激素(FSH)、促黄体素(LH)浓度。结果表明:雌二醇浓度在妊娠期达到峰值,分娩后急剧下降,空怀期比妊娠晚期下降了50.6%,差异显著(P0.05);孕酮浓度呈递减趋势,妊娠早期与空怀期相比差异显著(P0.05),妊娠早期与泌乳期相比差异显著(P0.05),空怀期和泌乳期比妊娠早期分别下降了44.9%和40.7%;促卵泡激素和促黄体素各时期相比均差异不显著(P0.05),两者变化规律一致。说明在建昌黑山羊繁殖周期中,雌二醇、孕酮、促卵泡激素、促黄体素对母羊妊娠、泌乳及间情等繁殖行为具有十分重要的作用。  相似文献   

9.
为探索番鸭等级前卵泡发育过程中主要生殖激素及卵泡发育的变化规律,试验以同批孵化、饲养条件相同、体况相近的产蛋期番鸭为对象,分别采集小白卵泡(SWF)、大白卵泡(LWF)、小黄卵泡(SYF)、大黄卵泡(LYF)。通过组织形态学方法观测卵泡的发育情况,酶联免疫吸附试验(ELISA)测定激素水平。结果表明:在等级前卵泡发育过程中,促卵泡素(FSH)和促黄体素(LH)呈现上升的趋势,且LYF时期浓度最高,差异不显著(P0.05);而孕酮(P4)和雌二醇(E2)均呈现下降趋势,从SWF至SYF时期极显著下降(P0.01),SYF至LYF时期,下降不显著(P0.05)。伴随卵泡的发育,颗粒细胞层和卵泡膜层不断增厚,且卵泡膜厚度在LWF至LYF时期增长极显著(P0.01)。由此可见,FSH、LH、P4、E2在番鸭等级前卵泡发育中起重要作用,且SYF阶段是番鸭等级前卵泡发育的关键阶段。  相似文献   

10.
目的:研究荷斯坦奶牛乳腺发育中乳糖的变化规律.方法:高效液相色谱法测定荷斯坦奶牛乳腺发育中乳糖的含量.结果:围产期,乳腺中才出现可检测到的乳糖;泌乳期乳糖含量增高,泌乳140d达到峰值;退化期乳腺乳糖含量迅速降低,退化30d含量很少.结论:不同生理时期,荷斯坦奶牛乳腺中的乳糖含量不同.  相似文献   

11.
A mastitis model in rats, induced by Escherichia coli infection, was established and the protective effect of Cytosine-phosphate-Guanosine (CpG)-DNA was determined. An E. coli suspension containing either 2 x 10(3) colony forming units (CFU)mL(-1)(EL group), 2 x 10(5)CFU mL(-1) (EH group), or (as controls) 100 microL phosphate buffer saline (CON group), was inoculated into the mammary glands 72 h after parturition. The rats were euthanased 24 h post-infection. The histopathological changes in mammary tissue in the EL group were mild, whereas the structural changes in the EH group were severe and polymorphonuclear leukocytes (PMNs) had accumulated in the mammary alveoli. Interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha and N-acetyl-beta-d-glucosaminidase (NAGase) were significantly increased in the mammary tissue from the EH group but not significantly changed in the EL group. On the basis of these findings, the potential protective effect of CpG-DNA on mammary glands was tested using a 2 x 10(5)CFU mL(-1) suspension. An intramuscular injection of either CpG-DNA (200 microg) or PBS (100 microL) was given immediately after parturition. At 72 h post-partum, 2 x 10(5)CFU mL(-1)E. coli (100 microL) were inoculated into the mammary glands of all rats. At pre-infection (0 h), and 8, 16, 24, 48 and 72 h after inoculation six rats were euthanased. CpG-DNA induced more rapid migration of PMNs from the blood to mammary tissue at the initial stage of infection, stimulated the secretion of IL-6 and TNF-alpha at different time points, reduced viable E. coli in mammary tissues and decreased the activity of NAGase. CpG-DNA also promoted the expression of its specific receptor TLR-9 mRNA in mammary tissue. The study showed that CpG-DNA protected against E. coli mastitis in this rat model.  相似文献   

12.
13.
Mammary epithelial cell (MEC) growth is reduced in continuously milked (CM) mammary glands, and administration of a mammogenic compound such as prostaglandin E(2) (PGE(2)) at parturition might improve MEC growth in CM tissue. The objectives were to 1) compare MEC turnover, ultrastructure, and gene expression in CM and involuting mammary tissue, and 2) evaluate the effects of CM and intramammary infusion of PGE(2) on early lactation MEC turnover, ultrastructure, mammary gene expression, milk yield, and composition. First- and second-lactation cows (n = 8) were used in a half-udder model, in which one-half was dry for 60 d (CTL) and the other was CM. Udder halves (n = 16) were assigned to a postpartum (PP) treatment of PGE(2) (+PGE(2); 875 mug/10 mL of medium-chain triglyceride oil) or no PGE(2) (-PGE(2)) treatment at parturition and at 72 h PP. Biopsies of CM and CTL quarters were obtained during milk stasis (MS) of the CTL half at 3 and 7 d after dry-off of the CTL half (3d-MS; 7d-MS) and postpartum (PP) at 2 and 4 d (2d-PP; 4d-PP). Milk yield was reduced (P < 0.01) in CM udder halves compared with CTL halves (13.2 vs. 22.1 kg/d), but reductions were less in second-lactation cows. The apoptotic index was greater (P < 0.05) in CTL glands than in CM glands (3d-MS, 0.52 vs. 0.11% and 7d-MS, 0.24 vs. 0.12, respectively). Proliferation of MEC was unchanged at 3d-MS, but was increased (P = 0.01) in CTL halves at 7d-MS compared with CM halves (3.10 vs. 0.93%). At 2d-PP, MEC proliferation was increased (P = 0.05) in CM halves compared with CTL halves (1.3 vs. 0.6%), but was unaffected by PGE(2) (P > 0.2). Apoptosis was elevated in early lactation regardless of treatment. Ultrastructure was unchanged by dry period length or PGE(2). In prepartum tissue, involution in CTL halves increased (P < 0.05) the expression of the proapoptotic genes Bcl-2-associated x protein (bax) and IGFBP5 and decreased (P < 0.05) alpha-lactalbumin expression compared with CM tissue. In PP mammary tissue, CTL halves expressed greater (P < 0.05) levels of ATP-binding cassette 1 (ABC1) and IGFBP5. Treatment with PGE(2) did not alter (P > 0.1) gene expression. The results confirm that CM reduced milk yield of cows with a mammary growth requirement. Reduced MEC turnover and milk yield were not alleviated by IMI of PGE(2), which indicates that peripartum PGE(2) concentrations in CM glands are not limiting mammary growth or milk synthesis.  相似文献   

14.
Let-7b, one of the let-7 family members, was studied for its regulative role in endometrial cells during early pregnancy in mice. According to real-time RT-PCR analysis, the expression of let-7b in epithelial cells increased gradually from day 1 to day 4 of preimplantation stages and reached the highest level on day 4. On the other hand, the highest level of let-7b in stromal cells was observed on day 1, although the expression was decreased on day 2 and increased significantly on day 4. By in situ hybridization, let-7b was also found to express in uteri during days 6-8 of pregnancy. Endometrial cells isolated from prepubertal mice were treated with steroid hormones, progesterone (P4), estradiol (E2) and P4 plus E2. After 96 h of culture in the presence of steroid hormones, the expression levels of let-7b were increased in the endometrial cells, although significant differences were only observed after P4 treatment in stromal cells and after individual E2 and P4 treatments in the epithelial cells. In association with the increased let-7b expression, the cell proliferation slope, measured by a MTT assay, significantly decreased in the presence of P4 and P4 plus E2 compared with the nonhormone and E2 treatment groups during 72-108 h of culture. Furthermore, results from transfection of let-7b into stromal cells isolated from day 4 pregnant mice or prepubertal mice demonstrated that let-7b attenuated the proliferation during the periods of time examined. After transfection of let-7b into mouse stromal cells isolated from day 7 of pregnancy, the expression of Basigin (Bsg), a matrix metalloproteinase (MMP) inducer, was suppressed, as well as that of MMP-9. In conclusion, this study clarifies the expression pattern of let-7b in uterine epithelial and stromal cells during preimplantation stages in mice, as well as the inhibitory effect of let-7b associated with steroid hormones on stromal cell proliferation and on the expression of MMP-9.  相似文献   

15.
Hormonal dependency of canine mammary tumours (CMT) has been studied over the last few decades. However, studies assessing the prognostic and predictive potential of serum and/or tissue steroid hormone levels are still scarce in CMT. To the best of our knowledge, this is the first report relating serum and tissue levels of steroid hormones and prognosis in dogs. Serum and tumour tissue from 45 female dogs with spontaneous CMT were included in the study. Moreover, serum and normal mammary tissue from 13 healthy female dogs were also included as controls. Steroid hormones were determined by competitive enzyme immunoassay. Overall, levels of steroid hormones in serum and tissue homogenates were significantly different between malignant and benign mammary tumours (p < 0.01), except for progesterone (P4) serum levels that revealed no statistical differences between groups. In malignant tumours, oestrone sulphate (SO4E1), dehydroepiandrosterone (DHEA), androstenedione (A4), testosterone (T) and P4 elevated tissue concentrations were significantly associated with tumour relapse and/or distant metastasis during follow‐up. A significant association was found between elevated tissue SO4E1 (p = 0.003), 17β‐oestradiol (E2) (p = 0.036), DHEA (p = 0.022), A4 (p = 0.001) and P4 (p = 0.013) concentrations and shorter disease‐free survival and overall survival in female dogs with malignant mammary tumours. The high levels of tissue steroids found in cases of poor prognosis open the possibility of additional new therapeutic approaches. Future clinical trials will be needed to clarify the usefulness of targeting steroid hormones in the treatment of this neoplastic disease.  相似文献   

16.
将40只雌性ICR小鼠,受孕后随机分为试验组和对照组。雌鼠产后10-11d,试验组经第4对乳头灌注LPS,对照组灌注生理盐水,分别于灌注后不同时间采集样本,组织学分析乳腺病理变化;分析对各组乳腺组织中TLR4和TNF-α mRNA表达变化。组织学结果显示,灌注1.5h后乳腺组织中炎性细胞增多,6、12h乳腺腺泡内有大量的炎性细胞浸润,腺泡结构崩解;6h TLR4 mRNA表达极显著高于对照组(P〈0.01);4个试验组中TNF-αmRNA表达极显著高于对照组(P〈0.01)。试验结果表明LPS能够增强TLR4和TNF-α mRNA表达。  相似文献   

17.
The forkhead box a (Foxa) protein family has been found to play important roles in mammals. Recently, the expression of Foxa2 was reported in the mouse uterus, and it was reported to be involved in regulation of implantation. However, the regulation of Foxa2 expression in the uterus is still poorly understood. Therefore, the present study was conducted to investigate the expressional profiles of Foxa2 in the rat uterus during the estrus cycle and pregnancy. Furthermore, the effect of steroid hormones and Hedgehog protein on the expression of Foxa2 was analyzed in vivo and in vitro. In this study, the level of expression of Foxa2 was low in the rat uterus during the different stages of the estrus cycle. However, the expression increased transiently during early pregnancy at 3.5 days post coitus (dpc) and decreased at 5.5 dpc. In ovariectomized rats, P4 treatment had no effect on the expression of Foxa2 compared with the expression in control animals. Moreover, the expression of Foxa2 in cultured epithelial cells was not increased by P4 treatment in vitro. However, Foxa2 expression was significantly decreased in the rat uterus after 24 h of E2 treatment. Treatment of cells with a recombinant Hedgehog protein significantly increased the expression of Foxa2. These results suggest that the expression of Foxa2 may transiently increase just before the implantation and it may be regulated by E2 and Hedgehog protein.  相似文献   

18.
The aim of this study was to investigate the (1) expression of progesterone membrane component 1 (PGRMC1), serpine mRNA binding protein 1 (SERBP1) and progesterone receptor (PR) mRNA and (2) protein expression levels of PGRMC1, SERBP1 and PR isoforms A and B in the bovine myometrium during the estrous cycle and early pregnancy. Uteri from cows on days 1-5, 6-10, 11-16 and 17-21 of the estrous cycle and weeks 3-5, 6-8 and 9-12 of pregnancy were used (n=5-6 per period). There were no changes (P>0.05) in PGRMC1 mRNA expression during the estrous cycle, while expression of SERBP1 and PR mRNA was the lowest (P<0.05) on days 11-16 relative to other days of the cycle. The highest mRNA expression of PGRMC1, SERBP1 and PR was found during pregnancy. There were no changes (P>0.05) in SERBP1 protein expression in cycling and pregnant cows, while the highest (P<0.05) PGRMC1 protein expression was found during weeks 3-5 of pregnancy. Similar protein expression profiles for PRA and PRB were found, and protein levels were highest on days 1-5 of the estrous cycle. From day 6 of the cycle, PRA and PRB protein expression decreased and were maintained at this lower level during pregnancy. In conclusion, our study assessed mRNA and protein expression levels of PGRMC1, SERBP1 and PR in the bovine myometrium during the estrous cycle and the first trimester of pregnancy. It is possible that progesterone (P4) affects myometrial function in a genomic and nongenomic manner.  相似文献   

19.
Insulin receptor (INSR) or insulin-like growth factor (IGF) signalling is speculated to be involved in mammary tumour development. Expression levels of members of the insulin receptor family (INSR, IGF1R, IGF2R, GHR) and their ligands IGF1and IGF2 were quantified in macro- and microdissected tissue samples of normal canine mammary gland, adenomas, carcinomas and their lymph node metastases to evaluate their potential impact on the carcinogenesis of canine mammary tumours. Normal mammary gland and adenomas had strong INSR expression, while carcinomas and metastases had significantly decreased expression. No differences were observed for IGF1R expression. IGF1, IGF2 and GHR mRNA expressions were strongly decreased in adenomas, carcinomas and metastases. INSR and IGF1R are therefore expressed in normal gland and adenomas and an increased stimulus by their ligands may be a proliferative stimulus in those tissues. However, decreased INSR expression carcinomas and their metastases render questionable its impact at late stages of carcinogenesis.  相似文献   

20.
In this study, solitary and combined effects of vitamin E and the calcium-channel blocker diltiazem were investigated in streptozotocin (STZ)-induced diabetic rats. Thirty male Wistar albino rats, weighing approximately 200 g were used. Diabetes mellitus was induced by a single intravenous injection of STZ at a dose of 65 mg/kg body weight. Five experimental groups were established as STZ-diabetic, STZ-diabetic + vitamin E, STZ-diabetic + diltiazem and STZ-diabetic + vitamin E + diltiazem. Vitamin E was injected intraperitoneally three times a week at a dose of 500 mg/kg body weight. Diltiazem was given orally every day at a dose of 25 mg/kg body weight. At the end of the study (10 weeks) blood glucose levels of diabetic rats, which had received vitamin E and diltiazem, had significantly decreased when compared with untreated diabetic rats (P < 0.02). Similarly, HbA1c levels had significantly decreased in diabetic rats which had received vitamin E (P < 0.05), diltiazem (P < 0.01) and vitamin E + diltiazem (P < 0.02) when compared with untreated diabetic rats. Liver glutathione levels of diabetic rats, which had received vitamin E (P < 0.01) and vitamin E + diltiazem (P < 0.05) had significantly increased when compared with untreated diabetic rats. Liver lipid peroxide levels had significantly decreased in diabetic rats, which had received vitamin E (P < 0.001) and diltiazem (P < 0.01). With respect to their metabolic and antioxidant effects, vitamin E proved superior to diltiazem.  相似文献   

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