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1.
The intracellular dynamics of norsalsolinol, a neurotoxin candidate causing parkinsonism-like symptoms, in PC12 cells was studied. We found that dopamine and norsalsolinol are co-localized to secretory granule layer by sucrose density gradient in norsalsolinol-treated PC12 cells. The norsalsolinol was actively taken up into isolated secretory vesicle fraction from PC12 cells with a Km value of 41.5+/-6.8 microM. The uptake of 10 microM of norsalsolinol was sensitive to reserpine (1 microM), an inhibitor of vesicular dopamine transporter, and dopamine, an endogenous substrate, but insensitive to GBR-12909, an inhibitor of dopamine transporter on plasma membrane. In norsalsolinol-treated PC12 cells, exposure to high K+ or ATP resulted in simultaneous release of norsalsolinol and dopamine. Time course of a release of dopamine and that of norsalsolinol evoked by 50 mM KCl or 100 microM ATP corresponded to each other. These releases were dependent on the concentrations of secretagogues. These data suggest that norsalsolinol is taken up with dopamine into secretory vesicle via vesicular catecholamine transporter.  相似文献   
2.
Lindane analogs, in which one or two chlorine atoms are replaced by various substituents, exhibit convulsive and lethal effects on Periplaneta americana (L.). Some analogs are as active as lindane. These effects are well related to the neuroexcitatory action which produces after-discharges in the central nervous system. Carbamate insecticides have potent convulsive and lethal effects on P. americana, which are also related to after-discharges produced in nerve cords. Convulsion caused by lindane analogs and carbamates is solely attributable to their neuroexcitatory effects on the nervous system, in spite of the difference in their ultimate modes of action.  相似文献   
3.
Lycopersicon esculentum cultivar Micro-Tom is a miniature tomato with many advantages for studies of the molecular biology and physiology of plants. To evaluate the suitability of Micro-Tom as a host plant for the study of pathogenesis, Micro-Tom plants were inoculated with 16 well-known fungal, bacterial, and viral pathogens of tomato. Athelia rolfsii, Botryotinia fuckeliana, Oidium sp., Phytophthora infestans, and Sclerotinia sclerotiorum caused typical symptoms and sporulated abundantly on Micro-Tom. Micro-Tom was resistant to Alternaria alternata, Corynespora cassiicola, and Fusarium oxysporum. When Micro-Tom was inoculated with 17 isolates of Ralstonia solanacearum, many isolates induced wilt symptoms. Agrobacterium tumefaciens also was pathogenic, causing crown galls on stem tissue after needle prick inoculation. In Micro-Tom sprayed with Pseudomonas syringae pv. tomato, P. s. pv. tabaci, or P. s. pv. glycinea, bacterial populations did not increase, and yellow lesions appeared only on leaves sprayed with P. s. pv. tomato. Tomato mosaic virus, Tomato aspermy virus, and Cucumber mosaic virus systemically infected Micro-Tom, which developed symptoms characteristic of other cultivars of tomato after infection with the respective virus. These results indicated that Micro-Tom was generally susceptible to most of the important tomato pathogens and developed typical symptoms, whereas certain pathogens were restricted by either hypersensitive resistance or nonhost resistance on Micro-Tom. Therefore, an assortment of Micro-Tom–pathogen systems should provide excellent models for studying the mechanism of susceptible and resistant interactions between plants and pathogens.  相似文献   
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Mycoplasma pneumonia of swine (MPS) lung lesions and immunogenic properties were compared between a Landrace line that was genetically selected for reduced incidence of pulmonary MPS lesions, and a non‐selected Landrace line. The MPS‐selected Landrace line showed significantly lower degrees of pulmonary MPS lesions compared with the non‐selected Landrace line. When changes in immunity before and after vaccination were compared, the percentage of B cells in the peripheral blood of the MPS‐selected Landrace line was significantly lower than that of the non‐selected line. Furthermore, the concentration of growth hormone and the mitogen activity of peripheral blood mononuclear cells in the MPS‐selected Landrace line showed significantly (P < 0.05) lower increases after vaccination than the non‐selected line. Conversely, the concentration of peripheral blood interferon (IFN)‐γ and salivary immunoglobulin A (IgA) after Mycoplasma hyopneumoniae vaccination was significantly higher in the MPS‐selected Landrace line than in the non‐selected line. Gene expression of toll‐like receptor (TLR)2 and TLR4 was significantly higher in the MPS‐selected Landrace line in immune tissues, with the exception of the hilar lymph nodes. The present results suggest that peripheral blood IFN‐γ, salivary IgA TLR2, and TLR4 are important immunological factors influencing the development of MPS lesions.  相似文献   
6.
Immunogenic properties and mycoplasmal pneumonia of swine (MPS) lung lesions were compared between the immunity‐selected Large White line and the non‐selected Large White line. The selected Large White line showed a higher level of pulmonary MPS lesions compared with the non‐selected Large White line. Subsequent to vaccination, the percentage of natural killer cells and T cells (CD3+CD4+CD8 and CD3+CD4?CD8+ T cells) were significantly increased in the non‐selected line but remained unchanged in the immunity‐selected Large White line. Secretion of Mycoplasma hyopneumoniae vaccine‐specific immunoblogulin G and phagocyte activity in peripheral blood were significantly higher in the immunity‐selected Large White line than in the non‐selected line. Expression of interleukin (IL)‐4 and IL‐6 messenger RNA in hilar lymph nodes was significantly lower in the immunity‐selected Large White line than in the non‐selected line. However, expression of IL‐10 in all immune tissues was significantly higher in the immunity‐selected Large White line. These results suggest that the selection for high immunity was not effective in increasing resistance to MPS lung lesions.  相似文献   
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8.
The aim of the present study was to clarify the effect of extracerebral dopamine (DA) on salsolinol (SAL)‐induced prolactin (PRL) secretion in goats. An intravenous injection of SAL or thyrotropin‐releasing hormone (TRH) was given to female goats before and after treatment with an extracerebral DA receptor antagonist, domperidone (DOM), and the PRL‐releasing response to SAL was compared with that to TRH. DOM alone increased plasma PRL concentrations and the PRL‐releasing response to DOM alone was greater than that to either SAL alone or TRH alone. The PRL‐releasing response to DOM plus SAL was similar to that to DOM alone, and no additive effect of DOM and SAL on the secretion of PRL was observed. In contrast, the PRL‐releasing response to DOM plus TRH was greater than that to either TRH alone or DOM alone and DOM synergistically increased TRH‐induced PRL secretion. The present results demonstrate that the mechanism involved in PRL secretion by SAL differs from that by TRH, and suggest that the extracerebral DA might be associated in part with the modulation of SAL‐induced PRL secretion in goats.  相似文献   
9.
To understand the influence of crossbreeding on Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics, two crossbred lines were characterized. One crossbred line, LaWa, was generated by crossing the MPS pulmonary lesion selected Landrace line (La) and the highly immune‐selected Large White line (Wa). The second crossbred line, LaWb, was generated by crossing the La line and the nonselected Large White line (Wb). The crossbred LbWb line (nonselected Landrace line × nonselected Large White line) and the La line were used as controls. The LaWa and LaWb lines had an intermediate level of MPS lung lesions between La and LbWb lines, although the difference was not statistically significant. After stimulation with sheep red blood cells (SRBCs), the LaWb and LaWa lines showed immune characteristics similar to that of the La line; the number of monocytes in peripheral blood increased, while B cells, T cells, secretion of SRBC‐specific immunoglobulin G, and interleukin (IL)‐13 decreased. Additionally, the number of natural killer (NK) cells and the expression of IL‐4 and IL‐17 were significantly higher in the LaWb and LaWa lines, respectively. These data suggested that crossbreeding of La and Wa lines resulted in the inheritance of some of the selected immune responses.  相似文献   
10.
Primary ovarian tumors are generally uncommon in rats used in toxicologic studies. A malignant Sertoli cell tumor was present in the ovary of a 19-week-old female Sprague Dawley rat. Macroscopically, the mass was white and firm, 10 × 13 × 17 mm in size, and located in the right ovary. Histopathologically, the mass was composed of nests of pleomorphic cells, which formed seminiferous-like tubules separated by a thin fibrovascular stroma. The tubules were lined by tumor cells, which had basally located nuclei and abundant eosinophilic and vacuolated cytoplasm. In some areas, the tumor cells were arranged in a retiform growth pattern, mimicking a rete testis/ovarii. Disseminated metastases to the surfaces of the mesentery, spleen and liver were also present. Immunohistochemically, many tumor cells were strongly positive for vimentin, estrogen receptor α and Ki 67. Some tumor cells were positive for pancytokeratin and inhibin α. These findings closely resemble those of an ovarian-derived human malignant Sertoli cell tumor. From our review of the literature, we believe this is the first report of a spontaneous malignant Sertoli cell tumor in the ovary of a young laboratory rat. This case might provide useful historical control information for rat toxicity studies.  相似文献   
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