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1.
The effects of oestrogen administration on 1 h post‐exercise cardiac muscle myeloperoxidase (MPO) and calpain activities were determined in female rats. Rats were ovariectomized and implanted for 2 weeks with either oestrogen (25 mg 17‐oestradiol) or placebo pellets or left with ovaries intact. Rats were then run for 1 h at 21 m min–1, 12% grade, killed 1 h post‐exercise and cardiac muscle and blood samples were removed. Control animals from each group were killed without prior exercise. Serum oestrogen levels in the order of the highest to lowest were; ovariectomized oestrogen replaced rats > intact ovaries rats > ovariectomized placebo rats. Oestrogen induced significant (P < 0.05) elevations in cardiac MPO activity at rest and at 1 h post‐exercise in ovariectomized rats. No significant elevations in cardiac MPO activity were evident in placebo ovariectomized or normal ovary rats at rest or post‐exercise. Cardiac calpain activities were similar in all unexercised groups. Ovariectomized placebo and intact ovary rats had significantly (P < 0.05) elevated cardiac calpain activities 1 h post‐exercise while calpain activity was not significantly elevated in hearts from ovariectomized oestrogen rats. These results demonstrate that oestrogen supplementation in ovariectomized rats induces elevations in cardiac muscle MPO activities at rest and at 1 h post‐exercise. This is opposite to the effect of oestrogen in post‐exercise skeletal muscle and implies a greater neutrophil infiltration into cardiac muscle caused by oestrogen. This effect cannot be explained by changes in 1 h post‐exercise cardiac muscle calpain activity, the elevation of which was suppressed by oestrogen administration. Oestrogen influences cardiac calpain activity similarly to its effect in skeletal muscle. Thus, oestrogen administration to ovariectomized rats induces elevations in cardiac MPO activity while suppressing cardiac calpain activity.  相似文献   
2.
目的 :观察雌性大鼠行去势后以及雌激素替代治疗海马结构蛋白激酶C ( proteinkinaseC ,PKC)阳性细胞的变化 ,通过该模型研究绝经期后女性情绪烦躁、记忆下降等神经精神症状的分子机制。方法 :将大鼠分为对照组、去势 3个月组和去势后雌激素替代治疗 3个月组 ,用免疫组织化学方法检测海马结构PKC阳性细胞的变化。结果 :PKC阳性细胞主要分布于下托和齿状回的颗粒层 ,其中齿状回内的阳性细胞较下托的多。去势 3个月组与对照组相比 ,齿状回内的PKC阳性细胞没有显著性减少 (P >0 .0 5 ) ,下托PKC阳性细胞显著减少 (P <0 .0 5 ) ;雌激素治疗组与对照组相比 ,下托细胞数量有所减少 ,但无显著性差异 (P >0 .0 5 )。结论 :海马结构下托PKC阳性细胞的减少可能在绝经后女性情绪烦躁、记忆下降等症状中起重要的作用。  相似文献   
3.
目的研究海藻酸钙(ALG-Ca)/枸杞多糖(LBPs)凝胶微球对小鼠骨质疏松的作用。方法采用静电液滴法制备ALG-Ca凝胶微球、ALG-Ca/LBPs凝胶微球,用扫描电镜观察微球结构。建立去卵巢小鼠骨质疏松模型,随机分为假手术组、模型组、单纯ALG-Ca微球组、单纯LBPs组、ALG-Ca/LBPs凝胶微球组,每组8只,每日灌胃1次,干预时间为12周,对各组小鼠股骨行HE染色观察骨组织形态变化,Micro-CT检测并经三维重建获得骨组织微观结构,对小鼠血清骨钙素(BGP)、血清碱性磷酸酶(BALP)、1型胶原羧基末端肽(CTX-1)进行检测。结果扫描电镜观察示凝胶微球呈均匀一致的微球形结构;OVX+LBPs、OVX+ALG-Ca/LBPs组的BGP、BALP、CTX-1均低于OVX+PBS组(P<0.05);OVX+LBPs、OVX+ALG-Ca/LBPs组骨体积分数(BV/TV)、骨小梁数目(Tb.N)及骨小梁厚度(Tb.Th)均高于OVX+PBS组(P<0.05),骨小梁间隙(Tb.Sp)小于OVX+PBS组(P<0.05),以OVX+ALG-Ca/LBPs组为最佳(P<0.01)。结论ALG-Ca凝胶微球是LBPs治疗骨质疏松的良好药物缓释载体;LBPs为天然植物成分,通过LBPs/ALG-Ca凝胶微球可以改善骨质疏松小鼠的骨代谢及骨微结构。  相似文献   
4.
补肾中药佳蓉片对去势小鼠骨丢失的预防作用   总被引:8,自引:3,他引:5  
目的 研究补肾中药佳蓉片 (JRP)对模型小鼠骨质疏松的影响 .方法 雌性昆明小鼠 6 0只随机分为 6组 ,行去卵巢术或假手术 .处理后分组为 :去卵巢组 (OVX) ,假手术组(Sham) ,去卵巢分为佳蓉片低剂量组 (JRP- L,10 0 mg·d- 1 ) ,佳蓉片中剂量组 (JRP- M,2 0 0 mg· d- 1 ) ,佳蓉片高剂量组 (JRP- H,40 0 mg· d- 1 )和 17β雌二醇组 (E2 ,10 μg·d- 1 ) .手术后灌胃上述药物 2 8d,测定股骨密度、骨生物力学性能、血清碱性磷酸酶 (AL P)、骨钙素 (BGP) .结果 各中药组的股骨骨密度均高于去卵巢对照组 (P<0 .0 5 ) ,与假手术组无差异 ;灌胃中药后骨结构力学参数显著性改善 (P<0 .0 5 ) ,同时 AL P,BGP显著性降低 (P<0 .0 5 ) .结论 补肾中药方剂可预防去卵巢引起的骨丢失 ,改善骨的生物力学性能  相似文献   
5.
目的:探讨补肾活血方治疗原发性骨质疏松症的疗效。方法:10月龄SD雌性鼠去卵巢建立绝经后骨质疏松模型。予以补肾活血方、尼尔雌醇水溶液灌胃治疗8周,观察有关指标的改变。结果:大鼠去卵巢后,含密度明显下降,模型复制成功。补肾活血方明显改善去卵巢大鼠的一般形态,显著提高去卵巢大鼠腰椎含密度,抑制卵巢大鼠尿羟脯氨酸/肌酐、尿钙/肌酐、血清骨钙素水平,而对血清尼尔雌醇水平未见明显影响。结论:补肾活血方可延缓实验性骨质疏松大鼠的含量丢失,改善其含代谢;此作用不是通过升高雌激素水平实现的。  相似文献   
6.
目的 观察炔诺酮和炔雌醇联合应用对去卵巢大鼠骨质疏松的预防作用。方法  4个半月龄大鼠双侧卵巢去除术后预防用药 90d。用骨组织形态计量学方法 ,测定大鼠胫骨近端松质骨静态参数和动态参数 ,观察骨和尿中有机质和无机质的含量 ,血清生化指标和器官指数。结果 炔诺酮6 0 μg·kg-1·d-1和炔雌醇 3 5 μg·kg-1·d-1联合应用可抑制去卵巢大鼠的破骨细胞活性 ,完全对抗其骨转化率增高和骨量丢失的骨质疏松症状 ,同时可使去卵巢大鼠的骨有机质含量增加和尿羟脯氨酸排出量减少。结论 炔诺酮和炔雌醇联合应用可预防去卵巢大鼠骨质疏松  相似文献   
7.
目的 研究染料木黄酮对去势大鼠骨密度、生物力学和形态学参数的影响。方法 将 4 7只雌性Wistar大鼠随机分为假手术组、去势对照组、去势 +雌激素组 (己烯雌酚每天 2 0 μg kgBW)、去势 +染料木黄酮组 (剂量分别为每天 2 5、5 0、1 0 0mg kgBW )。饲养 3个月后处死 ,测定骨密度、生物力学参数和形态学参数。结果 去势后大鼠骨小梁体积减少 ,平均骨小梁板密度降低 ,平均骨小梁板间隙增加 ,股骨骨密度降低 ,与假手术组相比均有显著性差异 (P <0 0 5 ) ,但最大应力只有降低的趋势。补充染料木黄酮后 ,骨小梁体积增加 ,平均骨小梁板厚度和密度增大 ;股骨骨密度和最大应力有改善的趋势。结论 染料木黄酮可以减少去势大鼠骨量的丢失 ,预防骨质疏松的发生  相似文献   
8.
背景:丹皮酚可抑制炎症,减轻慢性骨关节炎临床症状,作为一种不良反应小、更为安全的天然药物成分,探讨其对骨质疏松症的治疗作用具有重要的临床意义。目的:探究丹皮酚对去卵巢骨质疏松大鼠叉头框蛋白O3a(forkhead box O3a,FoxO3a)/Wnt信号通路及椎骨密度的影响。方法:雌性SD大鼠随机分为6组,每组10只。假手术组仅切除卵巢旁部分脂肪组织;其余50只大鼠均采用双侧卵巢摘除法制备去卵巢骨质疏松大鼠模型,模型制备成功后分为模型组、雌激素组[炔雌醇10μg/(kg·d)]、丹皮酚低、中、高剂量组[丹皮酚125,250,500 mg/(kg·d)],每组10只,灌胃给药;假手术组、模型组灌胃等量生理盐水,持续干预12周。ELISA法测定血清雌激素、骨保护素、骨钙素水平;采用双能X射线动物骨密度测定仪检测大鼠股骨及椎骨骨密度;采用骨科生物力学测试仪检测大鼠股骨及椎骨生物力学指标:弹性模量、最大载荷、屈服载荷;实时荧光定量PCR检测椎骨组织FoxO3a、Wnt2 mRNA表达水平;免疫印迹法检测椎骨组织FoxO3a、Wnt2及核内β-catenin蛋白表达。结果与结论:①治疗后,与假手术组比较,模型组L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平均显著降低(P<0.05),骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平显著增加(P<0.05);②与模型组比较,丹皮酚低、中、高剂量组大鼠L4,5骨密度、弹性模量、最大载荷、屈服载荷、血清雌二醇、骨保护素水平、椎骨组织Wnt2 mRNA及蛋白水平、核内β-catenin蛋白水平依次增加(P<0.05),血清骨钙素水平、椎骨组织FoxO3a mRNA及蛋白水平依次降低(P<0.05),且丹皮酚高剂量组均优于雌激素组(P<0.05);③提示丹皮酚可增加去卵巢骨质疏松大鼠椎骨骨密度,改善其骨生物力学状况,减轻骨质疏松,该作用可能与抑制FoxO3a、促进Wnt2/β-catenin通路激活有关。  相似文献   
9.
Perimenopausal syndrome occurs during the transition to menopause. Complementary and alternative medicine, especially Chinese medicinal plants, has manifested significant effects in alleviating perimenopausal symptoms. However, little research has been focused on the effects of Chinese medicinal plant on the immune function of the perimenopausal women. The present study aimed to explore the effects of Radix Astragali (RA) on the sex hormone levels and the interleukins of the ovariectomized female rats. 24 female Sprague-Dawley (SD) rats were randomly divided into model control group (MOD group), sham-operation group (SHAM group), RA group and estrogen group (EST group). After all the treatment ended, the serum levels of estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), interleukin-2 (IL-2), and interleukin-8 (IL-8) were measured using enzyme-linked immune-sorbent assay (ELISA) and the uterus was removed and weighed after blood exsanguinations immediately. In the MOD group, the serum levels of E2 were significantly lower, and the serum levels of FSH and LH were markedly higher than those of the RA group, EST group and SHAM group (P<0.05). In the RA group, the serum levels of E2 were significantly lower, and the serum levels of FSH were markedly higher than those of the SHAM group and EST group, respectively. In the MOD group, the serum levels of IL-2 and IL-8 were significantly lower than those of the RA group, EST group and SHAM group (P<0.05), and no marked differences existed among RA group, EST group and SHAM group in the serum levels of IL-2 and IL-8 (P>0.05). The uterine weight of the rats in the RA group, EST group and SHAM group were significantly higher than those of the rats in MOD group (P<0.05). There were no marked differences among the rats from RA group, EST group and SHAM group on the uterine weight (P>0.05). It is concluded that RA can significantly improve the immune functions of the ovariectomized female rats, although it cannot change the sex hormones levels as significantly as estrogen.  相似文献   
10.
Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed sham-operated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17β-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rats.  相似文献   
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