Stability and Dynamics of Forebrain Vasopressin Receptor and Oxytocin Receptor During Pregnancy in Prairie Voles

During pregnancy, females undergo several physiologically driven changes that facilitate adaptive behaviours and prepare the mother to care for her developing offspring. The nonapeptide hormone oxytocin is best recognised for its involvement in mammalian pregnancy and has been tightly associated with maternal care, in addition to its roles in pregnancy, parturition and lactation. A closely-related nonapeptide hormone, arganine vasopressin, has received considerably less attention for its role in pregnancy, although it has recently been implicated in modulating maternal care and aggression. In the present study, we examined the expression patterns of receptors for oxytocin (OXTR) and vasopressin (V1aR) over the course of pregnancy, ranging from non-mated virgin to immediately postpartum female prairie voles (Microtus ochrogaster). Unexpectedly, we found that OXTR was highly stable in all measured structures in the forebrain. V1aR was also stable throughout most of the brain. Two exceptions to this were found in the ventral pallidum (VPall) and the paraventricular nucleus of the hypothalamus (PVN); both significantly correlated with the length of time that females were pregnant. Changes in the PVN may reflect functional feedback in vasopressin release, or preparatory changes for ensuing maternal behaviour. The results also indicate an unappreciated role for VPall V1aR in pregnancy, which may relate to the function of the VPall in hedonic ‘liking’ and motivational ‘wanting.’ Taken together, our data indicate that, with a few compelling exceptions, nonapeptide dynamics during prairie vole pregnancy are largely limited to changes in the synthesis and release of oxytocin and vasopressin, and not the receptors to which they bind.     

东方田鼠血清被动转移抗日本血吸虫的保护力研究

目的　探讨被动转移东方田鼠血清抗日本血吸虫感染力及其作用机理。　方法　将东方田鼠血清通过尾静脉注射途径被动转移至小鼠 ,观察攻击感染日本血吸虫尾蚴后的减虫率、减卵率 ,并采用ELISA分别检测抗日本血吸虫童虫、成虫和虫卵的 8种抗体。　结果　与生理盐水对照组比较 ,东方田鼠血清受体小鼠获得的减虫率为 3 6.2 % ,减卵率为 5 4.0 % ;血清IgE、IgM、IgG及其亚类抗体均有升高 ,其中抗童虫抗原的IgG1抗体水平增幅最大。各试验组小鼠血清抗体水平差异均无显著性 (P >0 .0 5 )。　结论　东方田鼠抗日本血吸虫感染的天然抵抗力可通过血清被动转移至小鼠 ,使之获得部分抗血吸虫感染的保护力 ,该保护力可能是通过同时诱导受体小鼠Th1和Th2型免疫应答发挥作用的     

正常东方田鼠血清及脾细胞体外杀血吸虫童虫作用的初步观察

目的研究野生和繁殖东方田鼠血清和/或脾细胞在体外对日本血吸虫童虫的杀伤作用.方法东方田鼠血清和/或脾细胞与童虫在体外共培养,16～18h后在倒置显微镜下观察,计算童虫死亡率.结果东方田鼠血清或脾细胞对童虫的校正死亡率分别为67.36%土4.00%(野生鼠)和64.39%±5.86%(繁殖鼠)、66.02%±1.40%(野生鼠)和66.38%±2.18%(繁殖鼠);东方田鼠血清加脾细胞的童虫校正死亡率为76.68%±6.27%(野生鼠)和79.03%±8.00%(繁殖鼠),均显著高于单纯血清或脾细胞的校正死亡率;野生鼠和繁殖鼠对童虫的杀伤作用无显著性差异.结论东方田鼠血清和脾细胞均具有体外杀童虫作用,并表现出一定的协同杀伤作用,且野生鼠与繁殖鼠之间无显著性差异.     

东方田鼠血清及其不同部分对日本血吸虫童虫的体外杀伤作用

目的 对东方田鼠血清及其不同部分对日本血吸虫童虫的体外杀伤的可能机制进行初步探讨。方法 将血清初步分离成含蛋白部分及分子量小于20kDa的小分子部分，并分别观察了东方田鼠全血清、去补体血清、蛋白及小分子血清成分对体外培养童虫的杀伤，此外，还观察了蜕皮素对东疗田鼠血清杀伤作用的影响。结果 东方田鼠热灭活去补体血清对童虫的杀伤显著低于正常血清；感染及正常东方田鼠血清小分子在第48h及72h表现出一定杀伤作用(30％)，而血清蛋白在24h就有显著杀伤，但杀伤作用略低于全血清；蜕皮素对东方田鼠血清的杀伤无明显影响。结论 补体在东方田鼠血清杀伤机制中有重要作用。血清蛋白为体外杀伤的主要成分，可能与小分子成分协同参与杀伤。     

东方田鼠IgG3抗体抗血吸虫病作用研究

采用ELISA方法, 平行检测东方田鼠、 BALB/c小鼠和昆明小鼠在攻击感染前、 后的血清抗血吸虫童虫(SSA)、 成虫 (SAWA) 和虫卵(SEA) IgG3抗体水平, 并进行体内、 外试验, 观察IgG3抗体抗血吸虫效应。结果攻击感染后第4周, 东方田鼠抗SSA和SAWA的IgG3抗体水平增幅较大, 分别较感染前增加79.6%和49.6%, BALB/c小鼠IgG3抗体在攻击感染后无明显增加。野生和室内繁殖的东方田鼠的IgG3抗体所致童虫死亡率分别为昆明小鼠的5.88和2.35倍, 前者还诱生出较高的减虫率 (39.8%)。提示东方田鼠IgG3抗体可能是其抗血吸虫感染的主要免疫物质。     

四川省鼠疫防治30年回顾

目的分析四川省1981-2010年鼠疫防治的研究结果,为四川鼠疫防控工作提供对策与依据。方法统计、整理、分析四川省1981-2010年鼠疫相关工作资料,实验方法按照"鼠疫诊断标准"进行。结果通过调查,细菌学检测材料42 429份、分离鼠疫菌183株,鼠疫间接血疑试验血清29 980份、阳性251份,鼠疫放射免疫沉淀试验标本7 611份、阳性79份,鼠疫反向血疑试验检测标本833份、阳性31份,发现染疫动物7种,染疫媒介3种,发现青海田鼠型鼠疫菌和喜马拉雅旱獭型鼠疫菌,鼠疫发生在2县5个乡镇。结论证实了四川鼠疫自然疫源地的存在,发现了青海田鼠疫源地和喜马拉雅旱獭鼠疫自然疫源地。     

东方田鼠和小鼠感染日本血吸虫后血清NO的变化以及肝、肺病变的比较

目的了解日本血吸虫适宜宿主和非适宜宿主在感染后血清NO含量的变化规律以及肝、肺组织感染后的病变情况，以比较不同宿主对日本血吸虫感染的反应。方法东方田鼠和小鼠分别感染尾蚴1000条和40条，每2d分别剖杀2只，观察两宿主肝、肺变化，同时分别检测各宿主血清中NO的含量。结果小鼠和东方田鼠感染日本血吸虫后，肺部出现程度不同的出血现象。感染10d后出血现象均自行消失。其中，小鼠肝表观正常，但30d后肝中出现卵引起的内芽肿。东方田鼠在感染后6d肝中开始出现童虫所致病变，感染后第12～14d时逐渐减少，20d后病变消失。其间，小鼠和东方田鼠血清NO水平表现出不同的变化规律。东方田鼠感染后血清NO水平由正常的100μmol／L降到16μmol／L，18～20d恢复到原来的水平，完成一个完整和规律的循环。小鼠感染日本血吸虫后NO水平变化较大，第36d后，血清NO水平基本上维持在0～10μmol／L之间较低的、非正常水平。结论日本血吸虫非适宜宿主东方田鼠感染日本血吸虫后肝、肺病变特征以及NO水平变化与日本血吸虫适宜宿主小鼠不同，提示东方田鼠感染后体内存在一个敏感和系统的抗感染过程。     

瑞士北部农田周围野花地小型兽类种群结构特征的研究

目的评价野花地等生态保留带对小型兽类种群动态的影响. 方法我们在瑞士西北部选择3个野花地样地,采用标志重捕方法对普通田鼠种群结构特征和数量动态进行系统地研究.结果生态保留带适合于小型兽类特别是普通田鼠的生存,当周围耕地或农田受到人类干扰时普通田鼠和其他避难鼠种可生存在野花地中,但是,种群数量只有临时达到高峰.在3个野花地间普通田鼠种群数量有所差异,但是具有相同的季节性变化趋势,一般在春季随着植物盖度和食物丰富度的增加,种群数量也开始增加,中夏达到最高水平.秋季种群数量开始下降,但是进入冬季的个体数量相对也高.种群中雌雄个体年龄结构之间有明显的差异,雄性中亚成体的数量比雌性多,雌性中成体的数量比雄性多( χ2 =44.09, df=10, P< 0. 0 0 1, n=236).幼体的数量和繁殖期的雌性个体数量相关(r= 0.894, P<0. 000 1,n = 12), 亚成体数量和繁殖前期雌性数量相关(r= 0.893, P = 0.002, n=12), 繁殖期雌性数量和繁殖期雄性数量相关(r =0.99,P<0.0001,n=12). 种群性比基本保持1∶ 1,但具有月间波动趋势.结论生态保留带为小型兽类提供比较好的栖息地、食物、繁殖和隐蔽空间,因此,普通田鼠占优势地位并且种群数量有季节性变动趋势.     

Stability and potential inheritance of infanticidal behavior in prairie voles

Naïve female prairie voles show significant variability in their behavioral response to newborns. We investigated whether that behavioral response (a) was related to the quality of postpartum maternal behavior; (b) was affected by postpartum maternal experience; and (c) could be selectively bred. The behavior of females was recorded in three conditions: as naïve in a nonreproductive context, as single lactating (no male present), and as experienced mother in a nonreproductive context. Finally, females and males with similar behavioral response to newborns were selectively bred for three generation. Males were removed before the offspring was born. Our results revealed that (a) naïve females that attacked pups, spent more time distant from them after parturition than those that were maternal or ignored the pups (p < .05); (b) postpartum maternal experience did not reverse infanticidal behavior; and (c) at the third generation of selective breeding, 90% of the offspring of females that were nonmaternal as virgins, behaved as their mothers. These findings suggest that the infanticidal behavioral response is a stable behavioral trait and might be passed to the offspring. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 825–832, 2010.