补阳还五汤对大鼠脊髓损伤后红核脊髓束再生及功能修复的影响

为探讨补阳还五汤对脊髓损伤后轴突再生及功能修复的影响,将SD大鼠C3-C4右侧红核脊髓束(RST)横断后,分别以补阳还五汤和蒸馏水连续灌胃8周,用BDA顺行束路示踪方法检测轴突再生情况,采用自发性直立探究行为学测试方法评判前肢运动功能的恢复。结果显示:灌服补阳还五汤组的大鼠在损伤RST的尾侧可见少量的BDA标记纤维,伤侧前肢使用率明显高于蒸馏水组(P<0.01)。上述结果提示,补阳还五汤能促进大鼠横断的红核脊髓束轴突再生及部分功能修复。     

补阳还五汤对红核脊髓束横断后神经元的保护作用

目的:探讨补阳还五汤(BYHWD)对红核脊髓束横断后神经元保护作用的影响。方法:雌性SD大鼠随机分为3组:1.正常组;2.实验组:C3-4右侧红核脊髓束横断后灌服补阳还五汤;3.对照组:C3-4右侧红核脊髓束横断后灌服蒸馏水;用FG逆行示踪定位红核脊髓束神经元在红核的分布。动物存活8周后,Nissl染色计数红核脊髓束神经元并计算其平均截面积。结果:红核神经元的数目和平均截面积实验组分别减少了22%和35%,对照组分别减少了42%和64%。结论:BYHWT不仅提高了轴突横断后红核神经元的存活率,还对其萎缩有抑制作用。     

甲强龙、电针联合羊膜上皮细胞移植对脊髓损伤大鼠神经传导通路的影响

目的:探讨甲强龙、电针与羊膜上皮细胞(AECs)联合治疗对脊髓损伤(SCI)大鼠神经传导通路的影响。方法:成年雌性Wistar大鼠随机分成5组:SCI损伤对照组、甲强龙(MP)治疗组、MP+电针治疗组、MP+电针+AECs移植治疗组和假手术组。各组术后30 d行荧光红(FR)逆行示踪和神经电生理检测。结果:荧光红逆行示踪显示MP+电针+AECs移植治疗组脊髓损伤处可见大量有序的FR阳性神经纤维,在对应大脑皮质运动区和脊髓灰质后角追踪到数量较多的FR阳性神经元胞体,结构清晰。神经电生理检测显示该组感觉诱发电位与运动诱发电位的峰-峰值都有明显增加,潜伏期均明显缩短,与其他组比较,差异有统计学意义。结论:甲强龙、电针与AECs联合治疗大鼠脊髓损伤能够有效恢复神经传导通路,促进神经纤维再生。     

移植胚鼠神经干细胞对大鼠脊髓损伤后红核神经元损伤的影响

目的研究神经干细胞(NSCs)移植对大鼠脊髓损伤(SCI)后红核神经元的作用。方法5-溴脱氧尿嘧啶核苷(BrdU)法标记处于对数生长期的NSCs,采用电控脊髓损伤打击装置制作大鼠脊髓损伤模型。实验分为3组:NSCs组、SCI组和假手术组(Sham组)。SCI后3 d进行NSCs移植,用免疫组化法观察移植细胞的存活及迁移情况,用辣根过氧化物酶(HRP)逆行示踪技术标记红核神经元,并用四甲基联苯胺(TMB)呈色反应显示红核脊髓束神经元的存活情况,用行为学(BBB)评分法观察大鼠瘫痪肢体的恢复情况。结果在损伤脊髓区域可检测到BrdU标记的阳性NSCs,中脑HRP标记红核神经元数目明显多于SCI组(P<0.01),BBB评分亦明显高于SCI组(P<0.01)。结论体外培养的胚胎大鼠NSCs在移植到脊髓损伤区域后可存活和迁移,对SCI后中脑红核神经元具有保护作用,从而促进了大鼠肢体功能的恢复。     

三七总皂甙对大鼠脊髓损伤后背核和红核神经元存活的影响

目的探讨三七总皂甙对脊髓半横断后受损伤背核和红核神经元存活以及背核神经元表达一氧化氮合酶(NOS)的影响。方法25只成年雌性大鼠在施行脊髓半横断术后,被分为对照组、三七总皂甙低剂量组、三七总皂甙中剂量组、三七总皂甙高剂量组和L-NNA组。三七总皂甙组每天胃饲一定剂量的三七总皂甙,L-NNA组每d腹腔内注射L-NNA。术后30d取出脊髓和大脑行冷冻切片,做NADPH酶组化染色和中性红染色。结果脊髓半横断后,对照组损伤侧背核神经元和红核神经元数目明显降低,背核面积减少,背核NOS阳性神经元增多;应用三七总皂甙和L-NNA后,损伤侧背核神经元数目和背核面积有恢复性增加,尤其是高剂量三七总皂甙的效果更明显。三七总皂甙和L-NNA均可抑制受损伤的背核神经元表达NOS,三七总皂甙还可提高损伤侧红核神经元的存活率。结论三七总皂甙能够促进受损伤的背核神经元和红核神经元的存活,同时能够抑制受损伤的背核神经元表达NOS。     

嗅鞘细胞移植和左旋硝基精氨酸对大鼠脊髓损伤后背核神经元存活及其轴突再生的影响

目的 探讨嗅鞘细胞(OECs)移植和一氧化氮合酶(NOS)抑制剂左旋硝基精氨酸(LNNA)对大鼠脊髓损伤后,背核神经元存活及其轴突再生的影响.方法 将20只大鼠行脊髓半横断术后分为对照组、OECs组、L-NNA组和OECs L-NNA组.OECs L-NNA组在脊髓损伤处移植嗅鞘细胞,并注射L-NNA.术后30d时,应用NADPH酶组织化学、免疫组织化学、中性红染色、HE染色和荧光金逆行标记等方法,观察4组大鼠L1背核神经元存活及其轴突再生情况.结果 1.0ECs组、L-NNA组L1背核神经元存活数量均高于对照组,且分类计数显示,这两组对脊髓背核大、中、小神经元的存活均有促进作用,而OECs L-NNA组的促存活作用最显著.2.0ECs组和OECs L-NNA组脊髓损伤处可见再生的轴突,且L1背核可观察到被荧光金逆行标记的神经元胞体.3.与对照组比较,OECs组L1背核NOS阳性神经元增加,L-NNA组NOS阳性神经元减少,OECs L-NNA组NOS阳性神经元数量差异不明显.结论 嗅鞘细胞移植和L-NNA均可促进脊髓受损伤背核神经元的存活,两者联合应用可更好地促进受损伤的背核神经元存活及其轴突再生.     

雄性大鼠去势后下丘脑NOS神经元的分布

目的：探讨雄性大鼠去势术后下丘脑内一氧化氮合酶（NOS）阳性神经元的改变。方法：发育期雄性SD大鼠,分三组：假手术组,去势组和去势＋睾酮替代治疗组,利用黄递酶组织化学染色方法观察与比较各组大鼠与生殖相关各下丘脑核团内NOS神经元数目与密度,结果：在下丘脑的视前内侧核,视前室周核,正中隆起,弓状核均可见到NOS阳性标记细胞。去势术后视前内侧核内NOS神经元数目及密度降低,睾酮替代治疗可逆转,结论：一氧化氮在雄激素对下丘脑的反馈调节中起重要的介导作用。     

去卵巢后大鼠基底前脑NOS阳性神经元的变化及雌激素的作用

目的　研究基底前脑NOS阳性神经元在大鼠去卵巢之后的时程变化 ,为雌激素类药物替代防治绝经后老年性痴呆提供理论依据。方法　将 6 9只 3月龄雌性大鼠随机分为假手术组、去卵巢对照组及雌激素替代治疗组 ,各 2 3只 ,分别在术后 3d、1周、2周、4周、8周处死 ,脑切片用NADPH d组化方法染色 ,观察并和计数基底前脑各区NOS阳性神经元 ,并进行统计分析。结果　各组大鼠基底前脑各区NOS阳性神经元数目在去卵巢后先上升 ,2周时达到高峰 ,以后假手术组及雌激素替代组NOS阳性神经元数目逐渐下降 ,8周时达正常水平。去卵巢对照组斜角带核水平支及垂直支NOS阳性神经元数目却保持较高水平 ,在 8周时与假手术组及雌激素替代治疗组之间差异有显著性 (P <0 0 1)。结论　去卵巢后基底前脑NOS阳性神经元表达增加 ,而雌激素替代治疗对其有保护作用。     

灵芝孢子和一氧化氮合酶抑制剂对大鼠脊髓损伤后背核、红核神经元存活及轴突再生的影响

目的探讨灵芝孢子和一氧化氮合酶（NOS）抑制剂（L-NNA）联合应用能否促进脊髓半横断后受损伤的背核和红核神经元存活及其轴突再生。方法30只成年雌性大鼠被分为对照组、L-NNA组、灵芝孢子低剂量组、灵芝孢子低剂量＋L-NNA组、灵芝孢子高剂量组和灵芝孢子高剂量＋L-NNA组。灵芝孢子高剂量＋L-NNA组动物在T11脊髓段半横断后注射L-NNA和胃饲高剂量灵芝孢子。结果脊髓半横断后30d,对照组L1脊髓损伤侧背核神经元数量减少,NOS表达阳性。L-NNA组和灵芝孢子低剂量组损伤侧背核神经元增加,但NOS表达降低。灵芝孢子低剂量＋L-NNA组和灵芝孢子高剂量组损伤侧背核神经元明显增加,NOS表达显著降低。灵芝孢子高剂量＋L-NNA组损伤侧背核神经元最多,NOS表达最低,而且有些神经元胞体被荧光金标记。对照组和L-NNA组损伤侧红核神经元密度降低。灵芝孢子低剂量组和灵芝孢子低剂量＋L-NNA组损伤侧红核神经元密度提高。灵芝孢子高剂量组和灵芝孢子高剂量＋L-NNA组损伤侧红核神经元密度明显提高。结论灵芝孢子和L-NNA都能促进脊髓半横断后受损伤背核神经元的存活,两者联合应用能更好地促进受损伤的背核神经元存活及其轴突再生。灵芝孢子也能促进受损伤的红核神经元存活。     

GDNF及HSV—GDNF对坐骨神经损伤大鼠脊髓运动神经元Bcl—2表达的影响

目的：观察胶质细胞源性神经营养因子（GDNF）及单纯疱疹病毒（HSV）载体介导的GDNF（HSV－GDNF）对坐骨神经损伤大鼠脊髓运动神经元了Bcl-2表达的影响。方法：分别取坐骨神经损伤后4d、7d和14d大鼠（）分成对照组、GDNF组和HSV－GDNF组）的腰段脊髓）L4－6）,行石蜡包埋,切片、;用抗Bcl-2抗血清进行免疫组织化学染色,观察Bcl-2免疫反应（Bcl-2－IR）神经元数目,并在图像分析仪Bcl-2－IR阳性神经元作光密度的色谱分析。结果：1．坐骨神经损伤后4d、7d,GDNF组和HSV－GDNF组损伤侧脊髓运动神经Bcl-2－IR阳性神经元的数量和平均光密度均明显高于对照组损伤测,2．坐骨神经损伤后14d时,对照组、GDNF组和HSV－GDNF组损伤侧脊髓运动神经元对Bcl-2的表达已无明显差别。结论GDNF与HSV－GDNF能够增强坐骨神经扣内务 大鼠脊髓运动神经元Bcl-2的表达,减少神经元的退化死亡。     

雌二醇通过ERα抑制miR-16表达并促进蜕膜间充质干细胞生长

目的:研究雌二醇(E2)通过调控微小RNA-16(miR-16)的表达对胎盘蜕膜来源间充质干细胞(MSCs)活力的影响。方法:分别检测E2在正常孕妇及重度子痫前期(PE)患者外周血中的浓度。CCK-8法分析不同浓度E2对MSCs活力的影响。Real-time PCR分析不同浓度E2处理MSCs对miR-16表达的影响。探索E2通过何种受体调控miR-16表达。结果:与正常孕妇相比,重度PE患者外周血中E2浓度显著降低(P0.01)。5、10和100 nmol/L E2分别处理MSCs 48 h后,MSCs活力显著增加(P0.05)。5、10和100 nmol/L E2分别处理MSCs12 h后,miR-16的表达水平下调(P0.05),而用10 nmol/L E2处理MSCs不同时间(0 h、3 h、6 h、12 h和24 h)后,miR-16表达水平随着时间呈现明显下调趋势。在E2处理之前预先转染miR-16,细胞活力被显著逆转。E2处理MSCs之前6 h,用雌激素受体拮抗剂ICI 182780和他莫昔芬预预处理,E2对miR-16失去抑制作用。雌激素受体α(ERα)激动剂丙基吡唑三醇(PPT)及ERβ受体激动剂二芳基丙腈DPN分别处理MSCs后,仅PPT可明显抑制miR-16表达。结论:雌二醇可能通过ERα抑制miR-16表达,从而促进蜕膜MSCs的生长。     

Parvalbumin-containing neurons mediate the feedforward inhibition of rat rubrospinal neurons

The calcium-binding protein, parvalbumin and glutamic acid decarboxylase immunohistochemistry were used to locate candidate neurons mediating the inhibition of rat rubral neurons. A group of cells with small to medium-sized cell bodies that reacted positively to both were found in the red nucleus and its immediate vicinity. At the caudal nuclear level, these neurons gathered in the reticular formation, the pararubral area dorsolateral to the nucleus. As the nucleus expanded in size rostrally these neurons started to incorporate into the nucleus at about the anterior half of the middle nucleus and were all located within the rostral nucleus. Since these neurons were spatially segregated from the caudal nucleus we tested their connection by applying anterograde tracer to the pararubral area at the caudal red nuclear level. Labeled fibers with bouton-like swellings were found to enter the caudal nucleus and closely apposed rubrospinal neuronal cell bodies. These findings are consistent with our earlier observation that stimulating the pararubral area elicited a monosynaptic gamma-aminobutyric-acid(A) receptor-mediated inhibition on rubrospinal neurons in brainstem slices. In addition, the present study also shows that these inhibitory neurons remained unaltered in rats subjected to unilateral upper cervical rubrospinal tractotomy, suggesting that the reduction of pararubral stimulus-induced inhibition on rubrospinal neurons following spinal axonal injury resulted from causes other than the loss of these inhibitory neurons. In the rats, sensorimotor cortical fibers are known to reach the rostral red nucleus and the pararubral area but not the caudal nucleus. This prompted us to propose that neocortical inputs inhibit rubrospinal neurons through the activation of these PV-containing neurons. The proposed feedforward inhibitory circuit enables the cerebral cortex to disynaptically modulate the rubrospinal control over flexor motor execution.     

Comparison of the long-term effects of oral estriol with the effects of conjugated estrogen on serum lipid profile in early menopausal women

Objective: We investigated the long-term effects of oral estriol (E₃) on serum levels of total cholesterol (t-Cho), high-density lipoprotein cholesterol (HDL-Cho), low-density lipoprotein cholesterol (LDL-Cho), and triglycerides in early menopausal women. Methods: We studied 67 healthy early menopausal women who were treated for 48 months with 2.0 mg of E₃ plus 2.5 mg of medroxyprogesterone acetate daily (E₃ group, n=21), 0.625 mg of conjugated estrogen plus 2.5 mg of medroxyprogesterone acetate daily (CE group, n=19), or 1.0 μg of 1-hydroxyvitamin D₃ daily or 1.8 g of calcium lactate containing 250 mg of elemental calcium daily (control group, n=27). The serum levels of t-Cho, HDL-Cho, LDL-Cho, and triglycerides were evaluated at baseline and every 6 months. Results: After 48 months of treatment, the t-Cho decreased significantly by 4.3±2.1% (mean±SE) from baseline in the E₃ group, did not change in the CE group (−1.9±2.1%), and significantly increased (5.4±3.4%) in the control group. The HDL-Cho significantly increased in the CE group (10.7±2.4%), but not in the E₃ group (3.8±3.3%) or in the control group (−3.6±3.0%). The LDL-Cho significantly decreased in the CE group (−11.4±4.0%), did not change in the E₃ group (−5.2±3.6%), and significantly increased in the control group (11.8±6.3%). The triglyceride level decreased significantly in the E₃ group (−6.7±4.9%), whereas it significantly increased in the CE group (17.6±11.4%), and did not change in the control group (6.1±6.4%). Conclusions: Oral E₃ prevented a postmenopausal rise in the t-Cho. Oral estriol did not induce the hypertriglyceridemia that was seen after treatment with conjugated estrogen. Oral E₃ may be a useful alternative therapy in women with hypertriglyceridemia and in women who are reluctant to continue conventional hormone replacement therapy because of uterine bleeding.     

Profiles of plasma estrogens, progesterone and their metabolites after oral or vaginal administration of estradiol or progesterone

Doses of 100 mg of micronized progesterone (P) and of 0.5 mg of micronized estradiol (E₂) were administered vaginally and orally, respectively, in the early follicular phase of the menstrual cycle in six premenopausal women. In the second cycle, the same doses were administered in the same subjects, orally for P and vaginally for E₂. Serial blood samples were collected and the following steroids were assayed by highly reliable techniques: P, E₂, estrone (E₁), deoxycorticosterone (DOC), 5- and 5β-pregnanolone and the sulfates of E_l, E₂, and DOC. Circulating P and E₂ levels were higher after vaginal than after oral administration, while those of E₁ were similar after either route. Metabolites of P (DOC, DOCS and pregnanolone) were higher after oral administration. Concerning estrogen sulfates, E₁S concentrations were similar whichever the route, while those of E₂S were lower after oral than after vaginal administration. This study has confirmed that metabolism of ingested P and E₂ occurs mainly in the intestine. Moreover, P was predominantly metabolized to 5-reduced derivatives, whatever the route of administration. In view of the metabolic pathways which are operative and of the peripheral plasma levels which were found, the vaginal route appears to be more adequate than the oral one for hormone replacement therapy.     

Effective bleeding control and symptom relief by lower dose regimens of continuous combined hormone replacement therapy: A randomized comparative dose-ranging study

Objectives: We compared two different continuous combined hormone replacement therapy (HRT) regimens of estradiol valerate (E₂V) and medroxyprogesterone acetate (MPA) with a combination of micronized estradiol (E₂) and norethisterone acetate (NETA) to determine bleeding pattern, control of climacteric symptoms, lipid profile, endometrial and general safety in a 1-year multicenter study. Methods: 440 postmenopausal women were randomized to three treatment groups to receive: 1 mg E₂V+2.5 mg MPA; 1 mg E₂V+5 mg MPA; or 2 mg of E₂+1 mg NETA. After the first 6 months, the E₂V dose was increased to 2 mg in both E₂V/MPA groups. Information on bleeding was recorded on diaries by the women and intensity of climacteric symptoms was assessed using VAS scales. Physical and laboratory examinations, endometrial biopsy and vaginal ultrasonography were performed at baseline and follow-up visits. Results: Significantly fewer bleeding days were experienced in the first 3 months by women taking E₂V/MPA compared with women taking E₂/NETA. When the dose of E₂V was increased in the E₂V/MPA groups, an increase in maximum bleeding intensity was observed in the group receiving 2.5 mg of MPA, but not in the group taking 5 mg of MPA. All dose combinations effectively relieved climacteric symptoms and beneficial effects on the lipid profile were seen after 6 months in all groups. Tolerability and endometrial safety were good and no cases of hyperplasia were observed. More women discontinued treatment prematurely in the E₂/NETA group compared with either of the E₂V/MPA groups. The overall continuation rates ranged from 70 to 86%. Conclusions: These results confirm that lower dose combinations of continuous combined HRT are usually sufficient to control symptoms or avoid breakthrough bleeding. However, if higher E₂V dose is needed for symptom control, it should be combined with the higher dose of progestin (5 mg) to avoid bleeding disturbances. Flexible treatment regimens should be available for individualized HRT.     

Prostaglandin E(2) enhances axonal transport and neuritogenesis in cultured mouse dorsal root ganglion neurons

The effects of prostaglandin E₂ on axonal transport in cultured mouse dorsal root ganglion neurons were investigated by analysing the number of axonally transported particles under video-enhanced microscopy. Application of prostaglandin E₂ increased the number of particles transported in anterograde and retrograde directions. The EP₂ prostaglandin receptor agonist butaprost mimicked the effect of prostaglandin E₂, but the EP₁/EP₃ prostaglandin receptor agonist 17-phenyl trinor prostaglandin E₂ and the EP₃ prostaglandin receptor agonist M&B 28767 had no effect. The membrane-permeable cyclic AMP analogue dibutyryl cyclic AMP and the adenylate cyclase activator forskolin mimicked the effect of prostaglandin E₂. The protein kinase A inhibitor H-89 reversibly reduced the number of particles in both anterograde and retrograde directions. The effects of prostaglandin E₂ and dibutyryl cyclic AMP were blocked by H-89. Taken together with previous biochemical studies showing that prostaglandin E₂ increases cyclic AMP levels, the present results suggest that prostaglandin E₂ enhances axonal transport via the EP₂ receptor and cyclic AMP-dependent protein kinase A pathway. We further investigated the role of prostaglandin E₂ in neurite growth. Prostaglandin E₂ increased both the number of cells exhibiting neurites and the neurite growth rate, operating by a similar mechanism to stimulation of axonal transport.

Prostaglandin E₂ may modulate axonal transport to supply materials for morphogenesis as well as other functions in sensory neurons.     

Comparative endocrinological and clinical effects of percutaneous estradiol and oral conjugated estrogens as replacement therapy in menopausal women

Sixty-three healthy post-menopausal women participated in the study aimed at determining the efficiency of percutaneous administration of estradiol (E₂) giving physiological plasma levels of the estrogen to provide an efficient relief of climacteric and urogenital symptoms. Among these women, 31 had previous hysterectomy and were randomly allocated to one of the two estrogen replacement therapies while, similarly, the 32 women having an uterus were randomly divided between two groups who received in addition to estrogens, micronized oral progesterone. As estrogen, women received either E₂ by percutaneous administration (Oestrogel) or oral conjugated estrogens (Premarin). With Oestrogel, serum E₂ and estrone levels were within those seen during premenopause and showed a ratio close to 1.0. Climacteric symptoms were reduced or eliminated similarly in all groups. No change was noticed on the concentration of serum angiotensinogen with Oestrogel therapy while a 2.5-fold increase was found in women receiving Premarin. As indicated by the 24-week endometrial biopsy, the progestational response induced by oral progesterone at the dose used was sufficient in twenty out of thirty-two women to cause endometrial atrophy, thus suggesting the need for higher amounts of micronized progesterone in a proportion of women. The present data also indicate that Oestrogel provides efficient relief of climacteric and urogenital symptoms without exerting any detectable effect on hepatic function while maintaining the ratio of serum E₂/E₁ at the physiological value of 1.0.