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1.
The thyroid hormone 3,5,3'-triiodo-L-thyronine (T3) is a strong direct hepatocyte mitogen in vivo. The effects of T3 resemble those of peroxisome proliferators, which are known to induce hepatocellular tumors in rats. With the aim of studying long-term local effects of thyroid hormones on liver parenchyma, small pieces of thyroid tissue were transplanted via the portal veins into the livers of thyroidectomized male Lewis rats. At 1 week, 3 weeks, 3 months, and 18 months after transplantation, the transplants were found to proliferate, to synthesize thyroglobulin, and to release thyroxine and T3. At 3 and 18 months after transplantation, the hepatocytes of the liver acini downstream of the transplanted follicles showed an increase in cytoplasmic basophilia, a loss of glycogen, an enlargement and hyperchromasia of their nuclei, and a strong increase in cell turnover compared with unaltered liver acini. The altered hepatocytes exhibited an increase in the activities of glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, malic enzyme, mitochondrial glycerol-3-phosphate dehydrogenase, cytochrome-c-oxidase, and acid phosphatase; the activities of glycogen synthase and glycogen phosphorylase were strongly decreased. The hepatocytic alterations downstream of the transplanted follicles could be explained by effects of T3. On the other hand, they resembled alterations characteristic of amphophilic preneoplastic liver foci observed in different models of hepatocarcinogenesis.  相似文献   

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Subcutaneous autografts of ovarian tissue were made in unilaterally ovariectomized adult rats and were examined by light microscopy at various times after implantation. The implants were surrounded by a dense connective tissue capsule. They were well vascularized and contained follicles in varying stages of development as well as in different stages of atresia. Oocytes and fresh corpora lutea indicated that grafts ovulated in the presence of the in situ ovary but that the number of ovulations and their frequency were reduced when compared to normal ovaries or ovaries grafted in bilaterally castrated animals. Ovulation results in the formation of a cyst that contains follicular fluid, the oocyte, and cumulus in the ovarian stroma. Macrophages are associated with the oocyte-cumulus complex but are not prominent in association with the fluid in the cyst. It is suggested that follicular fluid is retained owing to inefficient resorption mechanisms and that this coupled with occasional ovulations results in the formation and maintenance of the large cysts.  相似文献   

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目的 评估成年大鼠冻存卵巢组织自体异位移植后的长期生殖、内分泌功能. 方法 78只Wistar成年大鼠,随机分为假手术组(1组,15只)、新鲜组织移植组(2组,24只)、冻存组织移植组(3组,24只)、去势组(4组,15只).将去势后成年大鼠的新鲜卵巢组织及冻存卵巢组织自体异位移植于肾被膜下,分别于移植后5、8、10个月处死各处理组1/3数量动物,取卵巢及子宫组织作组织学检查.通过阴道脱落细胞学检查、动情期雌、孕激素水平监测评估移植后卵巢组织的生殖内分泌功能. 结果 所有动物模型中,新鲜及冻存卵巢组织移植后都可观察到存活组织块.2、3组动情期雌、孕激素水平与假手术组无显著性差异(P>0.05),且均明显高于去势组(P<0.01).冷冻复苏后组织与新鲜组织各级卵泡构成比无显著性差异(P>0.05),各组不同时间取得的卵巢组织各级卵泡构成比相比较均无显著性差异(P>0.05).移植后5个月,2、3组原始卵泡明显减少,分别为假手术组的59.1%和54.5%. 结论 小块卵巢组织可耐受冻融过程;冻存卵巢组织自体肾被膜下移植后,卵巢组织形态无明显改变,原始卵泡总数虽然明显减少,但有成熟卵泡发育并排卵,并能长期维持生殖内分泌功能.  相似文献   

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The purpose of this study was to determine the effect of ethanol consumption on compensatory ovarian hypertrophy (COH) which occurs following unilateral ovariectomy. Holtzman rats, 40 days old, were either unilaterally ovariectomized or sham-ovariectomized. The rats were then placed into subgroups which would receive either an ad libitum chow and water diet, a liquid diet, or a liquid diet containing 5% ethanol. The animals were maintained on their respective diets for 11 days. The rats were killed at 51 days of age, and the ovaries and uteri were removed, weighed, and prepared for histological investigation. The results showed that uteri from ethanol-fed animals failed to develop epithelial glands and exhibited a condensed stroma in comparison to uteri from animals fed ad libitum or pair-fed to ethanol-fed rats. Also, rats that were fed ad libitum had a COH of 82 +/- 16% and rats that were pair-fed a liquid diet had 114 +/- 28% COH; rats that were fed the liquid diet containing ethanol did not experience compensatory ovarian hypertrophy (-3 +/- 10%). Histologically, the ovaries of rats fed ad libitum showed large numbers of corpora lutea and only a few mature ova. The histology of ovaries from pair-fed animals was similar to those from animals fed ad libitum. In contrast, the ovaries from the animals fed the ethanol diet had nearly twice as many mature ova but only one-fourth as many corpora lutea as the number seen in ovaries from the other groups. The data show that ethanol consumption inhibits COH by suppressing ovulation and the subsequent luteal formation.  相似文献   

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Pieces of marmoset ovary were frozen by slow cooling in 1.5M dimethylsulphoxide. The follicles in fresh and frozen tissuewere counted and examined for morphological appearance in stainedserial sections. The proportion of normal follicles was similarin fresh tissue and frozen tissue examined immediately afterthawing. Follicles at all stages of folliculogenesis up to thesmall antral stage survived freezing and thawing. Fresh andfrozen tissue was transplanted underneath the kidney capsulesof ovariectomized immunodeficient mice. The establishment ofgrafts was similar, and oestrogenic activity (cornificationof the vaginal epithelium) was observed in the recipients 20and 16 days after transplantation of fresh and frozen graftsrespectively. The total number of follicles and the proportionof normal follicles were similar in fresh and frozen grafts.Grafts of frozen tissue recovered between 7 and 15 days aftertransfer contained follicles up to the small antral stage ofdevelopment. Grafts recovered between 21 and 32 days containedfollicles at all stages of folliculogenesis, including largeantral follicles (1–2 mm diameter). Our results suggestthat freezing and thawing do not substantially damage marmosetovarian tissue, and the cryopreserved tissue retains its abilityto support the development of large antral follicles.  相似文献   

9.
B S Mitchell  S Peel 《Immunology》1986,58(2):297-301
The effects of withdrawal of ovarian hormones and absence of paternal antigens on numbers and distribution of cells expressing Ia, Thy 1.1 or leucocyte-common (LC) antigens in the rat metrial gland have been assessed. The distribution of these markers in non-pregnant uterus at various stages of the oestrous cycle has also been investigated. In primigravid rats at Day 15 of gestation, following ovariectomy on Day 12, marker distribution was not different from that in uninterrupted pregnancy. However, there was a significant increase in the percentage of cells expressing LC antigen, which was not accompanied by an increase in the percentage of the glycoprotein-containing, LC antigen-positive granulated metrial gland (GMG) cells. It was suggested that the accumulation of LC antigen-positive, non-GMG cells might represent the precursors of GMG cells. In deciduomata-bearing rats, there was a significantly lower percentage of LC antigen-bearing cells at Day 13 of pseudopregnancy than in pregnant rats at Day 13, but no difference in the percentages of GMG cells was noted. Cells expressing Ia, LC or Thy 1.1 antigens were detected in the endometrial stroma, surrounding endometrial glands and the luminal epithelium of the non-pregnant uterus.  相似文献   

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Nowadays, high-dose chemotherapy and radiotherapy treatments for cancer are more effective but can severely affect the ovarian follicular store, compromising the fertility of surviving young patients. A promising alternative to prevent fertility loss in these patients is the cryopreservation and transplantation of ovarian tissue. Slices of animal and human ovarian tissue have been shown to survive the cryopreservation process. After transplantation, follicular development and restoration of hormone secretion have been observed in animal and human studies. This review addresses recent developments on ovarian tissue transplantation in animals and humans. We also illustrate the indications and technical difficulties of the procedure and the ethical issues that should be considered.  相似文献   

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Several studies have demonstrated alterations in the dopamine (DA) system after traumatic brain injury (TBI). The present study investigated the temporal changes in DA tissue levels and metabolism at 1-h or 1, 7, 14, and 28 days after cortical impact or sham injury in rats. DA and DOPAC levels were measured by HPLC in the frontal cortex (FC) and striatum. DA levels were significantly increased at 1h in the contralateral FC and at 1 day in the ipsilateral FC versus respective sham groups. DA and DOPAC levels were significantly increased bilaterally at 1h in the striatum versus sham. These data indicate that TBI induces an early increase in DA and DOPAC, which returns to sham levels over time.  相似文献   

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目的 观察去势大鼠卵巢移植后海马神经元形态、尼氏体数量和雌激素膜受体GPR30表达的变化,评价卵巢移植对海马神经元功能的保护作用.方法 成年雌性SD大鼠分为对照组、去势组和卵巢移植组.对照组行假手术,去势组行双侧卵巢切除,卵巢移植组在切除双侧卵巢7d后,肾被膜下移植出生3d内乳鼠的卵巢.于移植后的7、14、21和28 d,尼氏染色观察海马神经元形态、尼氏体数量;免疫组织化学法和Western blot检测GPR30蛋白的表达.结果 去势组随去势时间延长,海马神经元排列散乱,胞体皱缩,核固缩深染,神经元尼氏体数量减少(P<0.05),GPR30表达减少(P<0.05).卵巢移植组随移植时间的延长,细胞形态逐渐好转并与正常形态接近,海马神经元内尼氏体数量和GPR30蛋白表达逐步恢复,并接近对照组.结论 卵巢移植可以逆转去势所致神经元形态改变,并提高GPR30蛋白的表达,促进海马神经元蛋白合成功能的恢复.  相似文献   

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背景:卵巢组织玻璃化冷冻技术作为一种快速、简便、经济的冷冻方式被逐渐应用于卵巢组织的保存。 目的:综述国内外关于卵巢组织玻璃化冷冻保存及移植的研究进展。 方法:由第一作者检索1995/2011 PubMed数据库及清华同方数据库有关卵巢组织玻璃化冷冻保存以及卵巢组织移植技术等方面的文献。 结果与结论:玻璃化冷冻是一个超高速的冷冻过程,形成高黏度的“玻璃样凝固状态”,可以避免由于冰晶形成所造成的细胞损伤。但至今玻璃化冷冻仍缺乏统一的标准化程序。影响卵巢组织玻璃化冷冻保存效果的主要因素有卵巢组织块的大小、冷冻保护剂的种类、渗透平衡的时间和温度、冷冻载体等。随着低温生物学的发展和卵巢组织冷冻保存效果的提高,卵巢组织的移植已经具备了一定的临床应用可行性。到目前为止,全世界已有一系列关于冻存卵巢组织移植后成功妊娠及分娩的报道,移植成功的关键在于减少缺血再灌注损伤和促进新生血管的形成。关键词:卵巢组织;玻璃化冷冻;移植;保存;综述 缩略语注释:SSV:solid-surface vitrification,固体表面;NIV:needle immersed vitrification,针浸润玻璃化冷冻法;DCV:direct cover vitrification,直接覆盖玻璃化方法 doi:10.3969/j.issn.1673-8225.2012.18.039  相似文献   

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Transplantation of fetal tissue in clinical practice in Russia has a solid experimental basis. “Tissue-tissue” relationships that are phylo- and ontogenetically fixed as characteristic of all systems of organs have been described in studies of Zavarzinet al. The method of tissue culture in the organism that was developed by Lazarenko in 1934 makes it possible to study the patterns of growth and transformation of tissues and organs in the living organism. This method has been used in studies of epithelial tissues of ecto-, endo-, and mesodermal origin. Five stages of the transplantation process have been identified: tissue depression, activation, tissue growth and differentiation, the period of functional activity, and atrophy. All tissues, except for endocrine tissue, which can live for a long time without atrophy, go through these stages, but in each tissue this process is genetically determined. This paper is focused on the close “tissue-tissue” relationships and presents characteristics of all epithelial tissues. Special attention is paid to the anterior portion of the gastrointestinal system and to the endocrine glands originating from it: adenohypophysis, thyroid gland, and thymus. The contribution of a normally functioning endocrine system to the successful transplantation of ovarian and mammary tissue is also discussed. After transplantation, epithelial tissues are transformed and assimilated in the recipient's organism. This may provide a basis for a novel approach to the problem of the immunological responsiveness of the organism. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 4, pp. 341–349, April, 1994  相似文献   

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The effects of oestrogen and progesterone, alone or in combination, on regional adipose tissue metabolism and oestrogen binding were examined in rats which were not only ovariectomized but also adrenalectomized to allow a study under conditions such that no endogenous sex steroid production occurred. Under these conditions no effects on food intake of the sex steroid hormones were found. 17-beta-oestradiol plus progesterone tended to increase lipoprotein lipase in the parametrial but not retroperitoneal fat depot, but no effects were found of oestrogen or progesterone alone. Oestradiol alone or in combination with progesterone clearly increased basal and norepinephrine-stimulated lipolysis, most pronounced in the retroperitoneal depot. Progesterone alone had no effect. Cytoplasmic 17-beta-oestradiol binding was highest in the parametrial fat depot in non-substituted rats and decreased dramatically after oestrogen administration. It was concluded that in ovariectomized-adrenalectomized rats, oestrogen alone or in the presence of progesterone facilitates lipolysis, a clear effect which is thus possible to elicit without adrenal hormones. Both sex steroid hormones alone or in combination, have no or weak effects on food intake and lipoprotein lipase activity, respectively. These metabolic events as well as cytoplasmic oestrogen binding show regional variations.  相似文献   

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背景:组织工程化心肌组织在组成结构上类似于心脏组织的三维电偶联网络和肌肉横纹,而且具有心肌组织样收缩功能,为病损心肌提供了修复的可能性。 目的:观察心肌细胞/胶原复合体移植后心肌梗死大鼠心室肌的心功能及电生理变化。 方法:将成年SD大鼠分为假手术组、模型组、移植组,后2组制作心肌梗死动物模型,假手术组仅开胸,不结扎冠状动脉。移植组移植心肌细胞与胶原材料复合组织,其他2组不进行移植。 结果与结论:①左室心功能:与假手术组相比,模型组左室舒张末期内径、左室收缩末期内径均显著增大(P < 0.01),左室射血分数和左室短轴缩短率显著降低(P < 0.01);移植组左室舒张末期内径、左室收缩末期内径、左室射血分数和左室短轴缩短率均未见明显增大或降低(P > 0.01)。②左室有效不应期变化:与假手术组相比,模型组梗死周边区有效不应期显著缩短(P < 0.01);移植组梗死周边区有效不应期较模型组延长,差异有显著性意义(P < 0.01)。③Cx43免疫荧光结果:假手术组、模型组和移植组大鼠缝隙连接蛋白43阳性表达依次呈现阳性,弱阳性,弱阳性。但移植组缝隙连接蛋白43阳性表达高于模型组。结果可见移植的心肌细胞/胶原复合体在组织和结构上形成电偶联网络和收缩偶联,能改善心肌梗死大鼠心室肌的收缩功能及电生理特性。  相似文献   

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8-Isoanalogs of estrone were studied for their ability to influence estradiol binding in the cytosolic fraction of uterine tissue from ovariectomized rats and for their uterotropic activity 24 h after injection into such rats. Two groups of estrone 8-isoanalogs with opposite biological effects were identified: those increasing estradiol binding in the cytosolic fraction of uterine tissue and those decreasing this binding. Uterogenic activity was exhibited by all of the compounds tested, with the exception of compound I. No correlation was found between the uterogenic activity of the isoanalogs and hormone-receptor interactions. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N o 2, pp. 165–167, February, 1995  相似文献   

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Ovariectomy reduces blood levels of sex hormones and considerably increases blood viscosity due to an increase in hematocrit and plasma fibrinogen content, disorders in viscoelastic characteristics of erythrocytes, and increase of their aggregation activity. Changes in the macrorheology are mainly responsible for the development of the hyperviscosity syndrome. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 7, pp. 101–104, July, 2008  相似文献   

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In the present study rats were unilaterally ovariectomized (ULO) and the surgically removed ovary was frozen for 13 days. After allowing the remaining ovary to compensate with respect to number of ova shed, the frozen graft was thawed and transplanted subcutaneously to determine the effect on ovulation number, cycle length, uterine weight, ovarian weight and plasma levels of estradiol-17 β (E2) and progesterone. Rats ULO at 45 days of age, which received an autograft 13 days later, had a decrease in the number of eggs shed as compared to control ULO rats (6.4 ± 0.8 vs. 11.1 ± 0.9 eggs, respectively) and a decrease in plasma E2 (14.5 ± 1.7 vs. 21.0 ± 1.5 pg/ml, respectively). No differences were observed in progesterone concentration, uterine weight, ovarian weight or cycle length. In contrast, rats ULO at 31 days of age, which received an autograft 13 days later, showed no differences in comparison to control ULO rats. Castrates which received ovarian autografts developed cycling vaginal smears and had increased E2 (31.9 ± 4.3 pg/ml) and decreased progesterone (18.3 ± 1.9 ng/ml) levels. Since ULO animals with autografts shed fewer ova, the present study demonstrates that the amount of ovarian tissue influences ovulation number either by utilization of gonadotropins or by an, as yet, undefined mechanism.  相似文献   

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