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61.
Folliculo‐stellate (FS) cells are non‐endocrine cells found in the adenohypophysis and are identified in many animals by the S100 protein marker. Although keratin is another FS marker in several animals, there is no information on localization of keratin in the avian adenohypophysis. In this study, localization of cytokeratin in chicken adenohypophyseal cells was investigated immunohistochemically. Basic cytokeratin (bCK)‐positive cells were arranged radially in the cell cords with their cytoplasmic processes reaching the basal lamina. The cell bodies encircled a follicle in the center of the cell cord. Furthermore, the bCK‐positive cells were also S100B‐positive. Growth hormone, prolactin, adrenocorticotrophic hormone, and luteinizing hormone β‐subunit did not co‐localize with the bCK‐positive cells. In addition, the bCK‐positive cells had a laminin‐positive area in their cytoplasm. Transmission electron microscopy observed agranular cells equipped with several microvilli that encircled a follicle. These results indicate that bCK‐positive cells in the chicken adenohypophysis may be a predominant FS cell population and produce laminin. It is suggested that they function as sustentacular cells to sustain the adjacent endocrine cells and the structure of the cell cords in the chicken adenohypophysis.  相似文献   
62.
Hepatic stellate cells (HSCs) are the main collagen‐producing cells in the liver. The HSC area and amount of collagen fibers are different between male and female chickens. This study was performed to confirm the effect of estradiol on collagen synthesis in the growing chicken liver. Blood estradiol levels in chicks were compared at 4 and 8 weeks of age, and the collagen fibril network in liver tissue was observed at 8 weeks by scanning electron microscopy. Intraperitoneal administrations of estradiol and tamoxifen to male and female chicks, respectively, were performed daily from 5 to 8 weeks of age. The areas of HSCs and collagen contents were measured in the liver tissue. The blood estradiol level was higher in females than in males, and the collagen fibril network was denser in males than in females at 8 weeks of age. Estradiol administration in males induced decreases in the HSC area and collagen content of the liver. Conversely, tamoxifen administration in females induced an increase in the HSC area but did not facilitate collagen synthesis. Based on these results, estradiol inhibits the area and collagen synthesis of HSCs in the growing chicken liver under normal physiological conditions.  相似文献   
63.
为探究雌激素是否通过交感神经调节雌性生殖系统的生理状态,试验选取雌山羊肠系膜后神经节,采用免疫组织化学SP法,检测雌激素受体α,β在肠系膜后神经节中的表达及分布。结果显示,雌激素受体α,β阳性产物在雌性山羊肠系膜后神经节广泛存在,强阳性产物存在于神经元胞膜和核中,阳性产物存在于整个神经元胞体以及核仁中。在神经节其他组成结构中也出现了阳性产物。表明在雌山羊肠系膜后神经元中存在雌激素受体,说明神经元对雌激素具有反应性;在神经节其他组成结构中出现阳性产物,说明雌激素可以经交感神经通路影响雌性生殖系统的生理机能,为研究雌性生殖系统的免疫神经调节提供了形态学证据。  相似文献   
64.
AIM: To investigate the effects of sorafenib on collagen synthesis in human hepatic stellate cells (HSCs). METHODS: HSC cell line LX-2 was used in vitro in this study. -proline incorporation assay was performed to measure the collagen synthesis. Immunocytochemistry was applied to detect type I collagen and real-time PCR was used to determine the mRNA expression of collagen α1 (I). RESULTS: Stimulation with platelet-derived growth factor (PDGF) induced the increase in type I collagen synthesis, while treatment with sorafenib (10.0 μmol/L) for 24 h markedly decreased the collagen synthesis. Sorafenib resulted in dose-dependent and time-dependent decrease in collagen synthesis in LX-2 cells in the absence or presence of PDGF by -proline incorporation assay. The inhibition rates were 22.69%, 37.52% and 71.74%, respectively, when LX-2 cells was treated with sorafenib at 10.0 μmol/L for 12 h, 24 h and 48 h. Sorafenib dose-dependently blocked the mRNA expression of collagen α1 (I) in LX-2 cells stimulated with PDGF. Sorafenib at the concentrations of 2.5 μmol/L, 5.0 μmol/L and 10.0 μmol/L down-regulated the mRNA expression of collagen α1 (I) in LX-2 cells by 58.66%, 67.06% and 81.64%, respectively. CONCLUSION: Sorafenib inhibits the collagen synthesis and blocks the expression of type I collagen at mRNA and protein levels in vitro in LX-2 cells. Therefore, sorafenib may be a potential therapeutic agent in the treatment of liver fibrosis.  相似文献   
65.
66.
AIM:To study the role of endothelin-1 (ET-1) in portal hypertension (PHT) induced by endotoxin. METHODS:Collagenase in situ perfusion was adopted to separate hepatic stellate cells (HSCs). HSCs was cultured on concretized collagen. ET-1 anti-sense oligonucleotide was added into the culture medium and then LPS was also added up to the concentration of 1 000 μg/L. The diameters of the concretized collagen were measured. Sense and mis-sense oligonucleotide were applied as control. ET-1 in the culture medium was detected by radioimmunoassay and ET-1 mRNA in HSCs was detected by RT-PCR. β-actin of HSCs was detected by Western blotting. RESULTS:The diameter of concretized collagen on which HSCs pretreated with ET-1 anti-sense oligonucleotide was 93.3%±3.8% the size of the primary. The diameter of concretized collagen of the control groups were 70.1%±4.8% and 70.5%±3.9% (P<0.05). ET-1 was (49.8±7.4)ng/L in the culture medium of HSCs pretreated with ET-1 anti-sense oligonucleotide and (329.8±34.9), (339.1±43.7)ng/L in the control medium (P<0.05). β-actin and ETI mRNA presented in HSCs pretreated with ET-1 anti-sense oligonucleotide was much less than that in the controls. CONCLUSION:ET-1 anti-sense oligonucleotide inactivated HSCs by counteracting the expression of ET-1, which may be helpful to control PHT induced by LPS.  相似文献   
67.
AIM:To investigate the effects of Arg-Gly-Asp-Ser (RGDS) tetrapeptide on proliferation, apoptosis and caspase 3 expression in FN-stimulated HSCs in vitro. METHODS:[3H]-thymidine incorporation, Annexin-V/Propidium Iodide double-labeled flow cytometry(FCM), TUNEL, scanning electron microscope and transmission electron microscopy were employed to estimate the influence of RGDS on proliferation and apoptosis of HSCs. The adhesion rates were observed by toluidine blue colorimetric assay. The expression of caspase-3 protein was detected by FCM. RESULTS:①Compared with control and FN groups, RGDS tetrapeptide at concentrations of 25 mg·L-1, 50mg·L-1 and 100 mg·L-1 inhibited the proliferation of HSCs (P<0.01), and the inhibition rates of 100 mg·L-1 at 12 h, 24 h and 48 h were 62.73%, 74.23%, 80.22%, respectively.②RGDS tetrapeptide induced the HSC apoptosis in dose-dependent and time-dependent manners(P<0.01). Observed with scanning electron microscope, the cell bodies and cellular processes of HSCs exposed to RGDS tetrapeptide were seen to be diminished. Microvilli on the cell surface decreased, became short even disappeared. Observed with transmission electron microscopy, the chromatins condensed, shrunk and aggregated along inside of nuclear membrane to exist in the form of ball, petal and crescent. Sometimes, apoptotic bodies formed. ③After exposure of HSCs to RGDS tetrapeptide for 2 h, the inhibition rates of adhesion were 8.82%, 29.41% and 45.59%, respectively, but that of RGES group was only 4.41%, P<0.01. ④ The expression of caspase 3 was obviously higher in RGDS tetrapeptide group than that in FN group, RGES tetrapeptide. CONCLUSION: These results suggest that RGDS tetrapeptide may inhibit proliferation and induce apoptosis of HSCs in both dose- dependent and time- dependent manners in vitro, which may be related to the abrogation of cell adhesion and caspase 3.  相似文献   
68.
AIM: In order to understand the pathological changes, characteristic of degeneration in optic nerve and retina after strike of optic nerve. METHODS: According to methods of Allen's spinal injury, a 600gcm-strike power was put on the intraocular portion of the optic nerve and created a striking injury on optic nerve. After a survival interval of 48 h, 1 week, 2 weeks, 4 weeks, 3 months, the animal's optic nerves and retinas were collected and fixed for morphological examination. RESULTS: Forty-eight hours after nerve injuries, the optic nerves were slight enlargement and vacuolation. In 1 week, the optic nerve began to degenerate in injured part and the glia cell had proliferated, but the forms of retinal ganglion cells(RGCs) were normal. In 2 weeks, the vacuolation and focal necrosis were appeared between nerve fiber. The number of RGCs began to decrease. Condensed nuclei presented in the retina. In three month, the diameter of the optic nerve decreased in injury part and collo-scar was formed. The phenomenon mentioned above was more obviously. The internal nuclear neurons and outer nuclear neurons appeared rare. The thickness of retina decreased. The number of RGCs began to decrease in 48 hours and progressed thereafter. It decreased about 3.35%, 13.23%, 19.74%, 23.20%, 29.28% in 48 h, 1 week, 2 weeks, 1 month, 3 months compared with the number of normal RGCs. RGCs began to apoptosis in 48 h. CONCLUSION: The model in this experiment could make definite uncompleted optic nerve and retina injuries. The degree of neuron injuries decreased from RGC, internal nuclear neurons to outer nuclear neurons. The number of RGCs began to decrease in 48 hours, and most quickly periods from 48 hours to one week.  相似文献   
69.
应用免疫组化链霉卵白素-生物素技术,结合行为学测定,观察了大鼠佐剂性关节炎在发生发展过程中,背根节(dorsalrootganglion,DRG)甘丙肽样免疫活性物质(galanin-likeimmunoreactivity,GAL-LI)的变化。结果表明,注入佐剂后动物形成急性关节炎时,DRG中GAL-LI免疫活性反应有所增强;在形成变态反应性关节炎时明显增强,表现为GAL-LI阳性细胞数明显增多,染色加深。在注入佐剂后14d,双侧L5DRG中GAL-LI阳性细胞数分别与该侧足容积呈明显的正相关。以上结果提示,GAL-LI与佐剂性关节炎的发生发展密切相关。  相似文献   
70.
Ten specimens of the head and neck of the Bactrian camel (Camelus bactrianus) were dissected to study the situation, arrangement and branches of the cranial cervical ganglion (ganglion cervicale craniale). The ganglion was a greyish fusiform structure, averaging 15–20 mm in length, 4–6 mm in width and 3 mm in thickness, located on the rostro-lateral surface of the longus capitis and covered by the mandibular gland. The branches of the cranial cervical ganglion included the internal carotid nerve, external carotid nerve, jugular nerve and the branches connecting with the glossopharyngeal, vagus, hypoglossal and first cervical nerves.  相似文献   
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