Effects of calcineurin on LTP of rats <Emphasis Type="Italic">in vivo</Emphasis>

Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus. Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic CN plays a role in the induction of LTP in the hippocampus of the rats.     

Mitochondrial permeability transition triggers the release of mtDNA fragments

Fragments of mitochondrial DNA are released from mitochondria upon opening of the mitochondrial permeability transition pore. Cyclosporin A, an inhibitor of pore opening, completely prevented the release of mitochondrial fragments. Induction of mitochondrial permeability transition and subsequent release of the fragments of mitochondrial DNA could be one cause of genomic instability in the cell.Received 22 September 2004; received after revision 11 October 2004; accepted 18 October 2004M. Patrushev, V. Kasymov and V. Patrusheva contributed equally to this work.     

小鼠同种异基因皮肤移植模型的建立

目的：为移植免疫及药物免疫机理研究建立小鼠同种异基因皮肤移植动物模型。方法：受体BALB/c分为A～E共5组,即对照组,5．0、7．5、10、20mg／kg环孢菌素A(CsA)剂量组,通过背-背法进行C57BL／6的全厚皮皮片移植,以探求通过较小剂量CsA及优化实验条件和护理方式建立供免疫机理研究的动物试验平台。结果：5．0、7．5、10mg/kg组相对于对照组皮片排斥时间无明显差别,而20mg/kg组植皮能较长时间存活。结论：20mg／kg的CsA剂量可以经济,快速地建立小鼠同种异基因移植动物模型。     

猪亲环素18的基因克隆与融合蛋白的表达

亲环素18(CyP18)具有肽脯氨酰顺/反异构酶活性,广泛存在于不同物种中,是一种高度保守的蛋白质.它能和免疫抑制性药物环孢菌素A结合,参与免疫抑制;此外,作为分子伴侣,它还加速蛋白质的折叠、组装和分解.从猪肝中提取总RNA,首次通过RT-PCR扩增出pCyP18,对其基因进行克隆和序列测定,并转入腚大肠杆菌中进行高效表达,得到纯化的pCyP18蛋白.     

Development of high blood pressure in spontaneously hypertensive rats is delayed by treatment with cyclosporin at an early age

Summary In spontaneously hypertensive rats the effect of the T-cell inhibitor cyclosporin was studied at different ages. If treatment was started at the age of 2 weeks the development of hypertension was delayed, but the ultimate level of blood pressure was not affected. These results indicate the involvement of immune mechanisms in the early development of hypertension in spontaneously hypertensive rats.     

Effects of calcineurin on LTP of rats in vivo

Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus. Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic CN plays a role in the induction of LTP in the hippocampus of the rats.     

弯颈霉属一新种的研究

云南省迪庆藏族自治州产的冬虫夏草经组织分离获得一纯种,在几种琼脂培养基上形成瓶梗及瓶梗孢子。瓶梗基部呈球形或椭园形膨大,瓶颈细长而弯曲,经鉴定隶属于弯颈霉属Tolypocladium W.Gams,但与弯颈霉属已知种有明显区别,故认为是弯颈霉属一新种,命名为中国弯颈霉Tolypocladium sinensis Li sp. nov,弯颈霉属的种类在中国从未发现和报导过,本文首次报导。中国弯颈霉经深层培养,培养基为蛋白胨葡萄糖,无机盐类,生长素等,26℃,PH5.2,振速100次/分,发酵周期12天。其分生孢子梗,瓶梗及瓶梗孢子的形态发生很大变异。发酵液经乙酸乙酯提取,减压浓缩,获粗提物,对几种丝状真菌具抑制作用,并与环孢菌素标准样品进行了对照和比较,证实中国弯颈霉能产生环孢菌素。     

肾移植术后应用普乐可复替换环孢霉素A减轻药物毒副作用的临床观察

目的：观察肾移植术后应用免疫抑制剂普乐可复(FK506)替换环孢霉素A(CsA)以减轻CsA所致毒副作用的临床疗效。方法：分别对47例CsA肝中毒、15例高脂血症、5例牙龈增生、5例多毛症的肾移植患用FKS06替换CsA治疗。停用CsA 24h后开始给予FK506,初始剂量根据患体重、肝功能损害程度及手术后的时间确定,服药后根据FK506谷值血药浓度调整剂量,术后半年内维持在8～10μg/L,术后1年6～8μg/L,术后1年以上4～6μg/L,严密监测患的肝肾功能、FK506血药浓度、血糖、血脂及临床表现。结果：47例CsA肝中毒的患改用FK506后,45例分别在9～45d肝肾功能恢复正常,2例改用FK506后,肝肾功能仍无明显好转,经治疗无效而死亡。15例高脂血症的患改用FK506治疗3个月后,血清总胆固醇水平明显降低。5例牙龈增生的患在改用FK506后,牙龈增生均得到控制,其中3例恢复正常。5例因多毛影响外观的患在改用FK506治疗后明显得到改善。结论：对应用CsA后出现严重的肝功能损害、多毛、牙龈增生及高血脂症的肾移植患改用FK506是一种较好的补救办法,同时不增加排斥反应的发生率,而且副作用少。