甲状旁腺素和二膦酸盐对骨密度和骨生物力学的影响

目的:研究应用甲状旁腺素和阿仑膦酸钠对激素性骨质疏松兔骨密度和生物力学的影响。方法:采用成年新西兰大白兔,随机分为对照组、激素模型组、甲状旁腺素和阿仑膦酸钠治疗组,9周后取股骨和腰椎行超声骨密度测量,再行股骨扭转、三点弯曲和腰椎压缩试验。结果:激素模型组的宽频超声衰减(BUA)、超声传导速度(SOS)值和骨生物力学参数较对照组有非常明显减少,甲状旁腺素和阿仑膦酸钠治疗组的BUA、SOS值和骨生物力学参数较激素模型组明显增加。结论:序贯应用甲状旁腺素和阿仑膦酸钠可以减少激素性兔骨量的丢失,预防骨质疏松的发生。     

伊班膦酸钠间断静脉输注治疗北京绝经后骨质疏松症的疗效

 目的 评价新一代双膦酸盐类药物伊班膦酸钠间断静脉输注对北京绝经后骨质疏松症的疗效及安全性。方法 研究纳入绝经后骨质疏松女性60例,年龄48~74岁,绝经年限3~32年,随机分为2组,治疗组每3个月静脉输注伊班膦酸钠2mg,对照组每周口服阿仑膦酸钠70mg,疗程12个月。疗效指标为腰椎及髋部骨密度（采用双能X线骨密度仪测量）、骨吸收指标血I型胶原羧基末端肽（酶联免疫吸附法测量）及骨形成指标碱性磷酸酶（自动分析仪酶法检测）。安全性指标包括血尿生化指标、心电图及不良反应。结果 59例患者完成研究。治疗12个月后,伊班膦酸钠组腰椎2-4、股骨颈及大转子骨密度增幅达6.3%,2.5%和0.1% (腰椎P <0.001,股骨颈P <0.01)。阿仑膦酸钠组腰椎、股骨颈及大转子骨密度改变率为 3.7%,4.9和-0.5% (腰椎和股骨颈P <0.001)。两组间治疗前后骨密度均无明显差别。伊班膦酸钠和阿仑膦酸钠治疗后ALP及CTX浓度均快速、显著下降,ALP降低15.8%和17.2%,CTX降低78.1%及43.2%（均P <0.001）。两组血钙磷水平、肝肾功能在正常范围内,伊班膦酸钠组常见的不良反应是首次输液后肌肉疼痛和低热,占26.7%,反酸、上腹不适是阿仑膦酸钠组主要的不良反应,占13.3%,患者可以耐受这些轻度的不良反应。结论 新一代双膦酸类药物伊班膦酸钠对于治疗绝经后骨质疏松症是安全而有效的。     

成骨生长肽羧基端片段及其衍生物对去卵巢大鼠骨生物力学性能的影响

目的探讨成骨生长肽羧基端片段(OGP10-14)及其衍生物G38I和G38K对去卵巢(OVX)骨质疏松大鼠股骨和腰椎生物力学性能的影响。方法56只3月龄SD雌性大鼠分为7组,1～6组行OVX手术,术后1～3组分别给予观察药物OGP(10-14)、G38I和G38K,4、5组分别给予利塞磷酸钠及阿伦磷酸钠作为治疗对照,6组术后给予安慰剂,7组为假手术组。术后第60天处死,分离股骨行三点弯曲实验,腰椎行压缩实验,检测并分析各组生物力学有关指标。结果OVX术后大鼠腰椎强度极限及最大应变分别下降为假手术组的80%和65%,变化较股骨明显,说明骨质疏松症早期,以松质骨为主的部位受累更加显著。OGP(10-14)及其衍生物治疗后,G38I,G38K组股骨弹性弯曲应力较OVX组显著升高,最大弯曲应力、弹性模量也有升高趋势,但差异无显著性。腰椎强度极限OGP(10-14)组升高达OVX组的1.28倍(P<0.01),与二磷酸盐治疗组近似,弹性模量OGP(10-14)组为OVX组的1.35倍。结论OGP(10-14)及其衍生物治疗后,在一定程度上提高了骨质疏松大鼠骨组织抗冲击、抗压缩的能力,改善了骨生物力学性能。     

阿仑膦酸钠可抑制骨质疏松性骨折的愈合

背景：阿仑膦酸钠作为治疗骨质疏松症的首选药物已被临床广泛应用。 目的：观察阿仑膦酸钠对骨质疏松性骨折大鼠股骨干骨折愈合的影响。 方法：将SD大鼠随机分成3组：假手术组,模型组和阿仑膦酸钠组。模型组及阿仑膦酸钠组于卵巢切除后4周进行右股骨干中段横行骨折,克氏针固定。阿仑膦酸钠组建模后皮下注射阿仑膦酸钠。 结果与结论：骨折造模后3及6周,阿仑膦酸钠组右股骨整体骨密度和远段骨密度高于模型组(P < 0.01),与模型组相比,阿仑膦酸钠组骨折端骨痂体积大、骨痂数量多,软骨性骨痂向骨性骨痂转换过程延迟,骨折愈合过程减慢,破骨细胞数量显著降低(P < 0.05)。结果证实,阿仑膦酸钠对大鼠骨质疏松性骨折愈合过程有抑制作用,其机制可能与阿仑膦酸钠抑制破骨细胞活性使骨痂钙化过程减慢有关。     

阿仑膦酸钠改善去卵巢大鼠的骨基质结构

背景：双膦酸盐可以提高骨密度、抑制骨吸收的作用已被临床所证实,但其对于骨骼基质结构的影响研究较少。 目的：实验通过观察双膦酸盐类药物——阿仑膦酸钠对骨结构及骨基质代谢的影响,探讨阿仑膦酸钠改善骨质量、提高骨强度的骨基质调控机制。 方法：实验建立去卵巢大鼠模型,用阿仑膦酸钠进行干预,同时设置模型组和假手术组进行对照。运用骨骼影像学、骨组织病理学和骨生物力学检测技术与酶联免疫吸附法观察阿仑膦酸钠对骨丢失大鼠骨密度、骨代谢、骨生物力学性能和骨结构的影响。 结果与结论：药物干预后4,8,12周,阿仑膦酸钠组骨密度均高于模型组(P < 0.05);药物干预8周后,与模型组相比,阿仑膦酸钠组骨代谢指标尿脱氧吡啶诺啉,血清Ⅰ型胶原羧基端前肽水平均降低(P < 0.05),腰椎和股骨的最大载荷、最大压强、模量以及Ⅰ型胶原不同交联形式的尿吡啶啉/脱氧吡啶啉值均增高(P < 0.05)。结果证实,阿仑膦酸钠能够对抗因雌激素缺乏导致大鼠骨量的丢失,提高生物力学性能,改善骨基质结构,同时恢复因去卵巢所导致的Ⅰ型胶原交联组分的改变。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

阿仑膦酸钠预防卵巢切除大鼠腰椎间盘退变

目的: 探讨阿仑膦酸钠对卵巢切除大鼠腰椎间盘退变预防作用及其作用机制.方法: SD大鼠随机均分为Sham组,双侧卵巢切除+盐水组(OVX+V组),双侧卵巢切除+阿仑膦酸钠(OVX+ALN组).处死前10d和4d分别给予四环素和钙黄绿素双荧光标记.取腰2椎体进行骨形态计量学分析,腰4～5腰椎及椎间盘进行VG特殊染色,免疫组织化学检测椎间盘基质金属蛋白酶-13(MMP-13)的表达,观察椎间盘的病理学改变并根据组织学评分系统对腰椎间盘的退变程度(LVD)进行评分.结果: 腰椎骨量OVX+V组低于Sham组及OVX+ALN组;腰椎间盘评分OVX+V组高于Sham组及OVX+ALN组; OVX+V组大鼠椎间盘中MMP-13表达高于OVX+ALN组、Sham组.结论:阿仑膦酸钠可预防卵巢切除大鼠腰椎间盘的退变,其作用可能与维持椎体骨量及微观结构,降低椎间盘中MMP13的表达,抑制基质的降解有关.     

脉冲电磁场治疗绝经后骨质疏松症的疗效观察

探讨脉冲电磁场(PEMFs)治疗绝经后骨质疏松症(PMO)的疗效及最佳治疗频次。比较PMO患者每周一次服用阿仑膦酸钠(共72周,阿仑膦酸钠组)和接受一个疗程PEMFs治疗(共5周,PEMFs组)在不同随访时间骨密度(BMD)、疼痛及平衡功能的改善情况。两组腰椎及全髋骨密度疗效统计量在分组后24周内无统计学差异(P≥0.05),在48周、72周PEMFs组低于阿仑膦酸钠组,差异有统计学意义(P0.05)。两组视觉模拟评分、时间限制的站起和行走测验以及Berg平衡量表评分的疗效统计量无统计学差异(P0.05)。与持续服用阿仑膦酸钠相比,一个疗程PEMFs的疗效至少能在24周内维持与阿仑膦酸钠相近,故PEMFs治疗PMO的适宜频次可能为半年一个疗程。     

阿仑膦酸钠治疗骨质疏松模型大鼠机制的串联质量标签蛋白质组学分析

背景：目前关于阿仑膦酸钠治疗骨质疏松症的作用机制及作用靶点，仍需深入研究。目的：探究阿仑膦酸钠调节骨质疏松模型大鼠骨代谢的作用机制，并进行差异表达蛋白生物信息学分析。方法：雌性SD大鼠随机分为模型组、阿仑膦酸钠组、假手术组，每组12只，前两组均采用去卵巢法建立骨质疏松症模型，造模4周后阿仑膦酸钠组大鼠予阿仑膦酸钠灌胃；另外两组予等体积生理盐水。连续灌胃12周后测定胫骨骨密度，采用串联质量标签联合液相色谱-串联质谱法联用技术对大鼠腰椎进行蛋白质组学分析，筛选出差异表达蛋白，并进行基因本体、京都基因和基因组百科全书通路及蛋白相互作用网络分析。结果与结论：(1)筛选出阿仑膦酸钠组与模型组组间上调/下调差异表达蛋白分别为32个/51个；(2)基因本体富集分析结果显示，差异表达蛋白主要参与结合、催化活性等分子功能以及细胞过程、代谢过程等生物过程；(3)京都基因和基因组百科全书富集分析结果显示，阿仑膦酸钠组/模型组组间差异表达蛋白功能主要参与泛酸和辅酶A的生物合成过程；(4)蛋白相互作用分析结果表明，阿仑膦酸钠组/模型组组间共同差异表达蛋白中Hspa1l、Enpp3、Unc45a、Myh9、Can...     

阿仑膦酸钠与雷洛昔芬对牙槽骨吸收的影响

背景：研究证明阿仑膦酸钠与雷洛昔芬对骨质疏松有抑制作用。 目的：建立实验性大鼠骨质疏松及牙槽骨吸收模型,评价阿仑膦酸钠与雷洛昔芬对骨吸收的防治作用。 方法：56只雌性SD大鼠建立骨质疏松及牙槽骨吸收的动物模型,实验动物分组：①去势+结扎组和单纯结扎组又分别分为3个亚组：阿仑膦酸钠组、雷洛昔芬组和非用药组。②单纯去势非用药组。③假手术组做空白对照。建模手术后第5日开始灌胃给药,1次/d,治疗3个月。用血生化指标、骨密度测量及组织形态学方法进行药效评价。 结果与结论：阿仑膦酸钠治疗组较雷洛昔芬组有更强的降低去势组碱性磷酸酶和血钙的作用;提高去势组骨密度。结果证实阿仑膦酸钠与雷洛昔芬均能减少骨质丢失,从而可以防止骨质疏松及病理性牙槽骨骨吸收,且阿仑膦酸钠作用较好。     

叶酸联合阿仑膦酸钠对绝经后骨质疏松患者骨密度、骨代谢指标和纤维细胞生长因子水平的影响

目的:探讨绝经后骨质疏松患者采用叶酸与阿仑膦酸钠联合治疗对其纤维细胞生长因子、骨代谢及骨密度指标的影响.方法:采用抽签法将 2020 年4 月至 2022 年6 月我科收治的绝经后骨质疏松患者 106 例随机分为两组(n=53),对照组口服阿仑膦酸钠 10 mg、硫辛酸 0.6 g,1 次·d-1,观察组口服阿仑膦酸钠 10 mg、叶酸 2 片,1次·d-1,治疗6 m后采用骨密度测定器测定股骨大转子、股骨颈、股骨干及第二腰椎-第四腰椎(L2-L4)骨密度,采用酶联免疫吸附法测定保护素(Osteoprotegerin,OPG)、核因子 кB受体激活因子配体(Receptor activator of NF-KB ligand,RANKL)、I型胶原交联C-末端肽(type Ⅰ C-tenninal cross linked peptide,CTX-1)和纤维细胞生长因子(Fibroblast growth facto,FGF)水平,采用电化学发光免疫分析法检测骨钙素(Bone glaprotein,BGP)水平,采用随访法观察各患者不良反应.结果:与治疗前相比,各治疗组的股骨大转子、股骨颈、股骨干及L2-L4 骨密度、OPG及BGP明显升高(P<0.05),其中观察组升高更显著(P<0.05);与治疗前比,各治疗组RANKL、CTX-1、FGF-23和FGF-21 明显降低(P<0.05),其中观察组降低更明显(P<0.05),两组各不良反应无统计学差异(P>0.05).结论:绝经后骨质疏松患者口服阿仑膦酸钠联合叶酸治疗,可有效调节其FGF水平,改善其骨代谢和骨密度情况,不良反应较少.     

Femur bone repair in ovariectomized rats under the local action of alendronate, hydroxyapatite and the association of alendronate and hydroxyapatite

An evaluation was made of the local action of alendronate sodium (A), hydroxyapatite (HA) and the association of both substances (A + HA), in different molar concentrations, on the femur bone repair of ovariectomized rats. Ninety-eight animals were divided into seven groups: control (C), starch (S), alendronate 1 mol (A1), alendronate 2 mols (A2), hydroxyapatite 1 mol (HA1), hydroxyapatite 2 mols (HA2) and the association of alendronate + hydroxyapatite (A + HA). Rats weighing about 250 g were ovariectomized and 2.5-mm diameter bone defects were made on the left femur 30 days later. Each experimental group had defects filled with appropriate material, except for group C (control). The animals were killed 7 and 21 days after surgery. Histological, histomorphometric and statistical analyses of bone neoformation in the bone defect site were performed. From the histological standpoint, the major differences occurred after 21 days. All specimens in groups C, S, HA1 and HA2 presented linear closure of the bone defect, and most animals in groups A1, A2 and A + HA showed no bone neoformation in the central area of the defect. No statistically significant difference was found among the experimental groups after 7 days; after 21 days, group HA2 presented the highest amount of neoformed bone. There was no significant difference among groups A1, A2 and A + HA in the two study periods. It was concluded that alendronate, either isolated or in association with hydroxyapatite, had an adverse effect on bone repair in this experimental model. Moreover, the hydroxyapatite used here proved to be biocompatible and osteoconductive, with group HA2 showing the best results.     

Sintered dicalcium pyrophosphate increases bone mass in ovariectomized rats.

Bisphosphonates are synthetic pyrophosphate analogs that can be used for the treatment of osteoporosis. Sintered dicalcium pyrophosphate, as a pyrophosphate analog, may be useful in the clinical setting for osteoporosis. In this study, an ovariectomized rat model is used to evaluate the effects of orally administered sintered dicalcium pyrophosphate on bone mass. Thirty-six female rats were used in this study. They randomly were divided into six groups: a negative normal control group, a positive osteoporosis control group, and ovariectomized groups treated either with alendronate sodium (one group) or sintered dicalcium pyrophosphate (three groups, each at a different level). The animals were sacrificed at 4 weeks after treatment. For all the rats, whole blood samples were obtained for the biochemical study. Bone ashes of long bones were measured and studied and histologic studies of cancellous bone were carried out. The ingestion of either alendronate or sintered dicalcium pyrophosphate did not have any deleterious effect on the major visceral organs. Ingestion of alendronate or sintered pyrophosphate decreased the bony porosity and increased bone mineral contents in the long bones of ovariectomized rats. Thus sintered dicalcium pyrophosphate can increase bone mass in the ovariectomized rat.     

Possible antiosteoporotic mechanism of Cicer arietinum extract in ovariectomized rats

Objective: The present study aimed to throw the light on the anti-osteoprotic mechanism of Cicer arietinum extract (CAE) seeds against ovariectomized (OVX) rats. Methods: Seventy female rats were divided into two groups. The first group (14 rats/group) represented normal rats (Sham operated) while the second group (56 rats/group) underwent bilateral ovariectomy (OVX). After one week of recovery from ovariectomy surgery, the second group was randomly subdivided into 4 subgroups (14 rats/ each subgroup). The rats administered orally; distilled water (vehicle) (1^st subgroup), Cicer arietinum extract (CAE) (500 or 1000 mg/kg body weight/day) (2^nd and 3^rd subgroups), alendronate (6.5 mg/kg mg/kg body weight) as a positive control one time/week (4^rh subgroup), daily for 10 weeks. Results: The present study demonstrated that ovariectomy caused significant decrease in bone mineral; density (BMD) and content (BMC), Bone-specific alkaline phosphatase (BALP), calcium (Ca), phosphorus (P), parathyroid hormone (PTH) and calcitonin levels. Furthermore, ovariectomy induced significant elevation of tartrate-resistant acid phosphatase 5b (TRAP 5b) and receptor activator of nuclear factor (NF-kappa β) ligand (RANKL) concentration. Conversely, osteoprotegerin (OPG) and OPG/RANKL ratio were decreased following ovariectomy. The present work suggests that CAE has antiosteoporotic action against ovariectomy effects and its activity may results from its phytochemical and/or phytoestrogen contents. Conclusion: The ongoing study speculates that the CAE exerts its action through regulation of RANK/RANKL/OPG system. As, CAE not only promotes osteoblast differentiation, but also up-regulates OPG and downregulates RANKL secretion in osteoblasts, subsequently prevents bone loss and osteoporosis.     

Osteogenic differentiation of bone marrow mesenchymal stem cells of ovariectomized and non-ovariectomized female rats with thyroid dysfunction

The objective of this study was to verify the osteogenic potential of the bone marrow mesenchymal stem cells (MSCs) of ovariectomized and non-ovariectomized female rats with hypo- and hyperthyroidism. Sixty two-month-old female rats were assigned to the following groups: (1) control (sham-operated), (2) ovariectomized (OVX’d), (3) hypothyroid sham-operated (Hypo-), (4) hypothyroid OVX’d, (5) hyperthyroid sham-operated (Hyper-) and (6) hyperthyroid OVX’d. After 135 days of treatment, the female rats were euthanized. We collected plasma to measure the levels of free T4, and the femur for extraction of MSCs. At 7 and 21 days of osteogenic differentiation of MSCs, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) conversion, alkaline phosphatase activity, mineralized nodule number and gene expression for collagen I, osteocalcin, bone sialoprotein and osteopontin were analyzed. The hypothyroid group presented a significant reduction in the osteogenic differentiation of MSCs. The hyperthyroid group did not present changes in the synthesis of mineralized nodules for MSCs at day 21 of differentiation. However, in ovariectomized rats, hyperthyroidism increased the osteogenic differentiation of MSCs characterized by the increase of the alkaline phosphatase activity, the number of mineralized nodules and the expression of osteocalcin, sialoprotein and osteopontin. Our results demonstrated that the hypothyroidism reduces the osteogenic differentiation of MSCs only in non-ovariectomized rats and that the hyperthyroidism increases the osteogenic differentiation of MSCs only in ovariectomized rats.     

Complete blood count and acetylcholinesterase activity of lymphocytes of demyelinated and ovariectomized rats treated with resveratrol

Resveratrol is a phytoestrogen that has many beneficial actions. This study aimed to evaluate the effect of resveratrol on the complete blood count (CBC) and the acetylcholinesterase (AChE) activity of lymphocytes of ovariectomized rats experimentally demyelinated by ethidium bromide (EB). Forty adult female Wistar rats (60 days, 200–220 g) were divided randomly into five groups (n = 4) to evaluate the demyelination phase and five groups (n = 4) to evaluate the remyelination phase. In each phase, the groups consisted of sham rats–G1; ovariectomized rats, not demyelinated, treated only with vehicle (ethanol 25%)–G2; demyelinated ovariectomized rats treated only with vehicle–G3; ovariectomized rats, not demyelinated, treated with resveratrol–G4; and demyelinated ovariectomized rats treated with resveratrol–G5. Only during the remyelination phase, CBC showed a significant difference (p < 0.05) in the number of monocytes between G2 and G5 groups. In the demyelination phase, there was a significant decrease (p < 0.05) in the AChE activity in the G4 group, while the G5 group was statistically similar to the G1, G2 and G4 groups. In the remyelination phase, there were no significant differences in the AChE activity among the groups. The treatment for 7 days with resveratrol with or without the experimental demyelization with EB appears to influence the AChE activity of lymphocytes, without changing the number of these cells in the circulation. However, in the remyelination phase, there seems to be stabilization in its effect on the lymphocyte AChE activity.     

洛伐他汀联合胰岛素干预双侧卵巢切除2型糖尿病SD模型大鼠骨折的愈合

文题释义： 糖基化终末产物(Advanced glycation end  products,AGEs)：是机体内蛋白质、脂肪酸或核酸的游离氨基与还原糖的醛基之间,通过非酶促糖基化反应产生的一组稳定的终末产物。它有多重存在形式：戊糖素、羧甲基赖氨酸、羧乙基赖氨酸、吡咯素、交联素等。 胰岛素抵抗：是机体对内源性或外源性胰岛素反应的敏感性下降,致使其不能促进血中葡萄糖进入细胞,而使得血糖异常增高的非生理状态,此时机体会代偿性分泌过多的胰岛素。 背景：2型糖尿病骨质疏松女性骨折患者,往往伴随血脂异常,在给予胰岛素控制血糖的同时,还常需应用他汀类药物联合治疗,但是这2种药物联合应用对于此类患者骨折愈合有何影响还未见报道。 目的：探讨洛伐他汀联合胰岛素对于去卵巢2型糖尿病大鼠骨折愈合过程的影响。 方法：实验方案经华北理工大学实验伦理委员会批准。雌性SD大鼠32只随机分为正常对照组、2型糖尿病并发骨质疏松骨折组、胰岛素治疗组和胰岛素联合洛伐他汀组。除正常组外,所有大鼠建立2型糖尿病并骨质疏松骨折大鼠模型,胰岛素治疗组和胰岛素联合洛伐他汀组大鼠在注射链脲佐菌素7 d建立2型糖尿病模型成功后,行皮下注射胰岛素直至实验结束,胰岛素剂量为早2-4 U、晚4-6 U;其余2组不做处理;胰岛素联合洛伐他汀组大鼠每日给予20 mg/kg洛伐他汀灌胃。在骨折后第3周时麻醉后处死大鼠,通过对各组骨痂进行影像学、临床检测及组织形态学分析,并检测其内骨形态发生蛋白2、血管内皮生长因子和Ⅱ型胶原蛋白的表达,来分析各组大鼠骨折愈合情况。 结果与结论：①2型糖尿病并发骨质疏松骨折组大鼠骨折愈合X射线评分、Micro-CT各项指标、组织形态学评分及血管内皮生长因子、Ⅱ型胶原蛋白的表达均较正常骨折对照组出现显著受损(P < 0.05);②经胰岛素治疗后,胰岛素治疗组以上指标均较2型糖尿病并发骨质疏松骨折组显著改善(P < 0.05),促进了模型大鼠骨折愈合;③但在胰岛素治疗基础上联合洛伐他汀治疗后,虽然进一步促进骨痂内血管内皮生长因子和骨形态发生蛋白2的表达(P < 0.05),但是对于骨折的影像学表现和骨痂组织的微结构并无显著改善。ORCID: 0000-0002-3455-8593(曹国龙) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

17-β雌二醇对卵巢去势大鼠延髓神经元超微结构的影响

目的观察雌激素对卵巢去势大鼠延髓神经元超微结构的影响。方法30只雌性成年SD大鼠随机分为去卵巢组(A组)、雌二醇组(B组)和假手术对照组(C组),A组和B组动物卵巢切除后10天超分别皮下注射生理盐水0.1 m l/d、17-β雌二醇20μg/kg/d。C组动物,只切开腹膜,不切除卵巢,手术后10天起分别皮下注射生理盐水0.1 m l/d。各组动物连续用药6周后,观察结果。结果血清雌二醇的浓度A组明显低于C组(P<0.01),B组明显高于A组(P<0.01),而B组和C组之间比较无差异。A组动物延髓孤束核神经元和神经胶质细胞超微结构有明显的损伤表现,细胞核形状不规则,核周间隙局部明显增宽,胞浆内有空泡,线粒体肿胀,嵴断裂;神经纤维有脱髓鞘,髓鞘板层分离,有空泡,线粒体肿胀。B组动物,在应用雌激素替代治疗后,延髓神经元的损伤表现明显减轻。C组神经元形态结构正常。结论雌激素对去势大鼠延髓神经元有明显地保护作用。