目的ω-芋螺毒素SO3是通过分子生物学手段从海洋生物线纹芋螺中提取的一种多肽,为新型、特异性N型电压敏感性钙离子通道阻滞剂。观察鞘内注射(it)ω-芋螺毒素SO3对大鼠坐骨神经慢性压迫性损伤(CC I模型)所致神经痛的镇痛作用,以及对背...目的ω-芋螺毒素SO3是通过分子生物学手段从海洋生物线纹芋螺中提取的一种多肽,为新型、特异性N型电压敏感性钙离子通道阻滞剂。观察鞘内注射(it)ω-芋螺毒素SO3对大鼠坐骨神经慢性压迫性损伤(CC I模型)所致神经痛的镇痛作用,以及对背根神经节(DRG)细胞内Ca2+含量的影响。方法♂SD大鼠40只,随机均分为5组,即正常对照组(N组)、CC I后14 d组(C组)、CC I 14 d it生理盐水组(CN组)、CC I 14 d it SO3 600 ng组(CS 1组)和CC I 7 d后连续鞘内注射SO3 30 ng.h-1共7 d组(CS 7组)。观察各组动物热痛觉过敏及机械刺激痛觉异常的反应阈值,并测定DRG细胞内Ca2+含量。结果CC I 14 d时结扎侧与非结扎侧热及机械刺激痛阈值均下降,同时DRG细胞内Ca2+含量也升高。it SO3后,结扎侧及非结扎侧痛阈值均升高,而DRG细胞内Ca2+含量降低。结论it SO3对慢性神经痛有镇痛作用,同时可以抑制CC I引起的DRG细胞内Ca2+含量增加,提示DRG细胞N型Ca2+电流在此伤害性信息传递中起作用。展开更多
Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity ...Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity to DNA cross-linking agents, such as mitomycin C （MMC）. To date, at least 12 FA genes have been found deleted or mutated in FA cells, and 10 FA gene products form a core complex involved in FA/BRCA2 DNA repair pathway-FA pathway. The ubiquitin E3 ligase FANCL, an important factor of FA core complex, co-functions with a new ubiquitin conjugating enzyme UBE2T to catalyze the monoubiquitination of FANCD2. FANCD2-Ub binds BRCA2 to form a new complex located in chromatin foci and then take part in DNA repair process. The deubiquitylating enzyme USP1 removes the mono-ubiquitin from FANCD2-Ub following completion of the repair process, then restores the blocked cell cycle to normal order by shutting off the FA pathway. In a word, the FANCD2 activity adjusted exquisitely by ubiquitination and/or deubiquitination in vivo may co-regulate the FA pathway involving in variant DNA repair pathway.展开更多
文摘目的ω-芋螺毒素SO3是通过分子生物学手段从海洋生物线纹芋螺中提取的一种多肽,为新型、特异性N型电压敏感性钙离子通道阻滞剂。观察鞘内注射(it)ω-芋螺毒素SO3对大鼠坐骨神经慢性压迫性损伤(CC I模型)所致神经痛的镇痛作用,以及对背根神经节(DRG)细胞内Ca2+含量的影响。方法♂SD大鼠40只,随机均分为5组,即正常对照组(N组)、CC I后14 d组(C组)、CC I 14 d it生理盐水组(CN组)、CC I 14 d it SO3 600 ng组(CS 1组)和CC I 7 d后连续鞘内注射SO3 30 ng.h-1共7 d组(CS 7组)。观察各组动物热痛觉过敏及机械刺激痛觉异常的反应阈值,并测定DRG细胞内Ca2+含量。结果CC I 14 d时结扎侧与非结扎侧热及机械刺激痛阈值均下降,同时DRG细胞内Ca2+含量也升高。it SO3后,结扎侧及非结扎侧痛阈值均升高,而DRG细胞内Ca2+含量降低。结论it SO3对慢性神经痛有镇痛作用,同时可以抑制CC I引起的DRG细胞内Ca2+含量增加,提示DRG细胞N型Ca2+电流在此伤害性信息传递中起作用。
基金This work was supported by the National Natural Sciences Foundation of China (No. 30470379).
文摘Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity to DNA cross-linking agents, such as mitomycin C （MMC）. To date, at least 12 FA genes have been found deleted or mutated in FA cells, and 10 FA gene products form a core complex involved in FA/BRCA2 DNA repair pathway-FA pathway. The ubiquitin E3 ligase FANCL, an important factor of FA core complex, co-functions with a new ubiquitin conjugating enzyme UBE2T to catalyze the monoubiquitination of FANCD2. FANCD2-Ub binds BRCA2 to form a new complex located in chromatin foci and then take part in DNA repair process. The deubiquitylating enzyme USP1 removes the mono-ubiquitin from FANCD2-Ub following completion of the repair process, then restores the blocked cell cycle to normal order by shutting off the FA pathway. In a word, the FANCD2 activity adjusted exquisitely by ubiquitination and/or deubiquitination in vivo may co-regulate the FA pathway involving in variant DNA repair pathway.
