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1.
AIM: To investigate the effect of IH764-3 on the apoptosis of H2O2-stimulated hepatic stellate cells(HSCs) and the alteration of focal adhesion kinase (FAK). METHODS: The proliferation of HSCs was examined by direct cell count and the apoptosis was determined by Annexin-V/PI labeling, while the morphological change was observed by light microscopy and transmission electron microscopy. In addition, FAK mRNA was detected by RT-PCR. RESULTS: H2O2 promoted the proliferation of HSCs. IH764-3 induced the apoptosis of HSCs in a dose-dependent manner. The HSC apoptotic rates of different groups were 6. 35%,9. 28%,15. 10%,19. 69%,respectively, after treated with different concentrations of IH764-3 for 48 h while H2O2 group showed 2. 30%. In 30 mg/L group, the apoptosis rates were 6. 73%、10. 34%、15. 10% for the indicated time periods(12 h, 24 h, 48 h). In the presence of IH764-3, FAK mRNA decreased. The FAK mRNA reduction began at 2 h after adding IH764-3. CONCLUSION: IH764-3 induced the apoptosis of HSCs. Down-regulating the expression of FAK mRNA may be one of its mechanisms.  相似文献   
2.
AIM: To investigate the effect of Chinese herbs, Ganxianfang(GXF), on rat hepatic stellate cells (HSC) proliferation and collagen synthesis. METHODS: Two types of herb serum, portal venous serum and circumferential venous serum, were prepared from rats infused intragastrically with 16, 8, 4 times adult dose of GXF decoction. HSC isolated from rat liver were processed with the above sera in vitro. Then we mensurated the radioactivity of HSC admixed with [[3H]H]proline and [[3H]H]thymine to judge the effect on proliferation and collagen synthesis of HSC. RESULTS: Both two types of serum collected 0.5, 1, 2 h after intragastrical infusion inhibited HSC proliferation (P<0.05), and the serum collected 1 h after intragastrical infusion had the strongest effect (P<0.05). Portal serum decreasea collagen synthesis (P<0.05), but circumferential serum had no effect (P>0.05). CONCLUSION: Inhibition of HSC proliferation and decrease of collagen synthesis may contribute to the GXF antifibrotic action.  相似文献   
3.
AIM: To investigate the role of microRNA-29b (miR-29b)-mediated TGF-β/Smad signaling pathway in the activation of hepatic stellate cells (HSC) and its effect on the progression of hepatic fibrosis in rats.METHODS: Hepatic liver fibrosis rat model was established, and its HSC were isolated. Normal rat HSC were also obtained and identified in vitro. RT-qPCR and Western blot were used to detect the alterations of miR-29b, TGF-β/Smad signaling pathway-related proteins and liver fibrosis marker proteins in the acquired cells. Finally, the direct targeting binding of miR-29b to TGF-β1 was identified by dual-luciferase reporter assay system.RESULTS: With the activation of HSC, the expression of miR-29b gradually decreased (P<0.01), while the expression of collagen type I and α-smooth muscle actin gradually increased (P<0.01). At the same time, the expression of Smad2/3/4 was significantly increased, and the expression of Smad7 was significantly decreased (P<0.01). Dual-luciferase reporter assay showed that miR-29b bound directly to "UCUCUCCGU" in the 3'UTR of TGF-β1, indicating that TGF-β1 was a downstream target gene of miR-29b.CONCLUSION: miR-29b may be involved in the inhibition of HSC activation and migration, thereby inhibiting the process of liver fibrosis. The biological function of miR-29b may be through the direct targeting of TGF-β1, thus regulating and inhibiting the TGF-β/Smad signaling pathway.  相似文献   
4.
AIM: To investigate how the function of retinal ganglion cells (RGCs) change in the midterm of retinal pigmentosa (RP) in rd1 mice (a transgenic animal model of RP). METHODS: The action potentials from multiple RGCs in rd1 mice at postnatal 20 d (P20) or normal C57 mice (control) were simultaneously recorded by multi-electrode array recording. The functional changes of surviving ganglion cells were evaluated by comparing spontaneous and light-evoked activities of RGCs between rd1 and control mice. The extent of photoreceptor degeneration was verified by immunohistochemical staining. RESULTS: Immunohistochemistry results showed the thickness of the retinal photoreceptor layer of rd1 mice was significantly lower than that in normal mice at P20. According to the light response properties, we classified ganglion cells into 6 subgroups: ON sustained, ON transient, ON-OFF sustained, ON-OFF transient, OFF sustained and OFF transient RGCs, with a very tiny percentage of OFF sustained RGCs (1.0%~3.1%). The percentage of RGCs remaining light responsive in rd1 mice was significantly lower than that in C57 mice. The average spontaneous spiking rate for rd1 RGCs was overall significantly increased compared to that in C57 cells, whereas different RGC types had different changes. The light-induced responses and light sensitivities of all types of RGCs in rd1 mice were both significantly lower than those in C57 mice. CONCLUSION: The photoreceptors of rd1 mice are severely degenerated in the midterm of retinal degeneration. The functions of RGCs in rd1 mice in the midterm of degeneration decay obviously, with variance in different RGCs types.  相似文献   
5.
The effects of the oxadiazine insecticide indoxacarb and its N-decarbomethoxylated metabolite (DCJW) on tetrodotoxin-resistant (TTX-R) voltage-gated sodium channels in rat dorsal ganglion neurons were studied using the whole-cell patch clamp technique. Indoxacarb and DCJW suppressed the peak amplitude of action potentials, and DCJW exhibited a faster time course and higher potency than indoxacarb in the blocking effects. In voltage-clamp experiments, indoxacarb and DCJW suppressed TTX-R sodium currents in a time-dependent manner without a steady-state level of suppression. IC50 values for indoxacarb and DCJW on TTX-R sodium currents were estimated to be 10.7 and 0.8 microM after 25 min of bath application, respectively. DCJW was about 10 times more potent than indoxacarb in blocking TTX-R sodium currents. Although the suppressive effects of indoxacarb were partially reversible after washout with drug-free external solution, no recovery of sodium current was observed in DCJW treated neurons after prolonged washout. In current-voltage relationships, both indoxacarb and DCJW blocked the sodium currents to the same degree in the entire range of membrane potentials. The sodium conductance-voltage curve was not shifted along the voltage axis by indoxacarb and DCJW at 10 microM. In contrast, the steady-state inactivation curves were shifted in the hyperpolarizing direction by indoxacarb as well as by DCJW. Based on these results, it was concluded that indoxacarb and DCJW potently blocked the TTX-R sodium channel in rat DRG neurons with hyperpolarizing shifts of the steady-state inactivation curves, suggesting preferential association of the insecticides to the inactivated state of sodium channels. The small structural variation between indoxacarb and DCJW resulted in clear differences in potency for blocking sodium channels and reversibility after washout.  相似文献   
6.
7.
A 2.5‐year‐old intact male Roborovski hamster (Phodopus roborovskii) was presented with a large subcutaneous mass overlying the abdomen, affecting the animal's ambulation and access to different compartments of the cage through narrow tubing. Ultrasound examination delineated a well‐circumscribed mass in the subcutis of the caudoventral abdominal region. The mass was surgically excised and on cytologic examination showed, in a background of blood, a small population of individually arranged oval to spindle‐shaped cells that exhibited a moderate degree of anisokaryosis, coarsely stippled chromatin, one or more prominent nucleoli, and lightly basophilic well‐defined cytoplasmic processes. Histologically, the mass was composed of interlacing streams and bundles of pleomorphic spindle cells (ganglion‐like cells) with variable amounts of collagenous stroma. The neoplastic cells exhibited moderate features of malignancy. These cells stained intensely with vimentin, but not with any other markers, including antibodies to cytokeratin AE1/AE3, S100 protein, desmin, smooth muscle actin, synaptophysin, neurofilament, and androgen receptor. Based on histologic features, the mass was diagnosed as an atypical fibrosarcoma. This is the first report of an atypical fibrosarcoma in a Roborovski hamster and one of few reports of atypical fibrosarcoma in domesticated hamsters overall.  相似文献   
8.
通过 PF/HM 和 Azan 染色对柞蚕咽下神经节神经分泌细胞的组织和功能的研究,表明:柞蚕咽下神经节内仅有一类神经分泌细胞,即 A 细胞。它与脑神经分泌细胞中的 A 细胞属于不同亚型,预蛹至化蛹初期为其分泌活动的盛期。脑与咽下神经节之间存在着通过 A 细胞的神经联系。咽下神经节神经分泌物经神经轴突通过神经血器官释放至靶组织。笔者经研究论证,作出柞蚕存在 DH 的推断(陆明贤等,1987),咽下神经节 A 细胞分泌物很有可能就是 DH,由于其分泌量尚不足以引起的蛹本身滞育,故决定柞蚕蛹滞育的主导因素,仍然是 PTTH 的停止分泌.  相似文献   
9.
AIM: To investigate the effects of siRNA-mediated Smad3 silence on proliferation and apoptosis in activated hepatic stellate cells (HSCs).METHODS: HSCs-T6 cells were divided into 3 groups: blank group, negative control group and siRNA-Smad3 transfection group. The siRNA-Smad3 was transfected into HSCs-T6 cells. At different time points after transfection, cell proliferation was measured by CCK-8, cell apoptosis was detected by flow cytometry, and protein levels of P53 and Bcl-2 were determined by immunocytochemistry.RESULTS: HSCs proliferation was significantly inhibited at the time points of 24 h, 48 h and 72 h after transfection. Meanwhile, the apoptosis of HSCs was significantly increased in siRNA-Smad3 transfection group (P<0.01). Compared to the control cells, the protein expression of P53 was significantly increased while Bcl-2 protein was significantly decreased 48 h after transfection in siRNA-Smad3 transfection group (P<0.01).CONCLUSION: The siRNA-mediated Smad3 silence significantly inhibits HSCs proliferation and induces apoptosis by up-regulating the P53 expression and down-regulating the Bcl-2 expression in HSCs.  相似文献   
10.
旨在探索山羊颈前神经节是否具备接受γ-干扰素(interferon-γ,IFN-γ)作用的条件,是否有IFN-γ受体(interferon-γreceptor,IFNGR)的存在,进而明确神经调节与免疫调节之间的关系。分别取雌雄成年山羊颈前神经节各5对,用免疫组化SP法和PCR方法检测IFNGR在颈前神经节的表达情况。结果表明,在山羊颈前神经节的神经元、卫星细胞和神经纤维均有IFNGR免疫阳性产物分布,但主要分布于神经元胞体,IFNGR在神经元胞体的相对表达量显著高于非神经细胞结构(P0.05)。在山羊颈前神经节扩增到IFNGR1基因的cDNA片段全长376bp,与绵羊、牛、野猪、家兔、褐家鼠IFNGR1基因同源性分别为98%、97%、84%、73%、66%。在山羊颈前神经节中IFNGR主要在交感节后神经元表达与分布,具备对IFN-γ刺激做出反应的条件,提示山羊颈前神经节可能作为IFN-γ对靶器官免疫内分泌调节途径和自主神经对靶器官调节的神经途径之间相互协调的关键点。  相似文献   
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