Scintillation counter

这项应用是为了一种新的闪烁计数器，这是一种测量生物组织或其他材料的小样本中放射性的机器。我们需要这个来取代我们在1984年购买的老化计数器，它现在的灵敏度大大降低，并且出现了多个机械问题。我们正在用它来追踪人与人之间的氚(~3H)类固醇。我们正在研究的可能性是，类固醇激素，如雌激素，最强大的雌激素，不仅在个人内部起作用，而且在个人之间传递。我们发现雌二醇和其他小类固醇是由成年雄性老鼠和其他哺乳动物排泄的。这与两种众所周知的信息素效应有关：1)接触不熟悉的成年雄性导致雌性受孕；2)接触不熟悉的成年雄性导致未成年雌性青春期提前。这些效应都可以通过给女性注射雌二醇来模仿。我们正在用老鼠做实验，我们从男性的系统中追踪~H-雌二醇进入他们的尿液和其他排泄物，然后在附近的女性的子宫和大脑中测量这种~H-雌二醇。这是非常有意义的，因为有证据表明，子宫内雌激素的小幅升高会干扰早孕。此外，雌二醇会促进青春期，因为子宫的生长是由雌二醇自然驱动的，女性的性行为自然是由大脑下丘脑中的雌二醇所刺激的。因此，这种新的闪烁计数器对于我们识别重要生殖信息素的化学性质的研究至关重要。一个新的闪烁计数器也将有助于这个实验室测量血液、尿液和其他介质中的类固醇的能力，因为它将允许我们使用敏感的放射免疫分析程序。这个计数器对于继续实验室中已有学生的研究至关重要，它将帮助未来的学生在信息素动力学和内分泌干扰方面进行创新研究。这将有助于确保该实验室保持竞争力，为基础生殖科学和生殖毒理学做出实质性贡献。

This application is for a new scintillation counter, which is a machine that measures radioactivity in small samples of biological tissues or other materials. We need this to replace an aging counter that we purchased in 1984, which now has very reduced sensitivity and multiple mechanical problems. We are using this to trace tritiated (3H-) steroids between individuals. We are examining the possibility that steroid hormones such as estradiol, the most powerful estrogen, not only act within individuals but also pass between individuals. We have found that estradiol and other small steroids are excreted by adult male mice and other mammals. This is associated with two well-known pheromonal effects: 1) the loss of pregnancy in females caused by contact with unfamiliar adult males, and 2) early puberty in juvenile females exposed to unfamiliar adult males. These effects can both be mimicked by injecting females with estradiol. We are conducting experiments with mice where we trace 3H-estradiol from males' systems into their urine and other excretions, then measure this 3H-estradiol in the uterus and brain of nearby females. This is very meaningful given evidence that small elevations of estradiol in the uterus can disturb early pregnancy. Furthermore, estradiol promotes puberty, as growth of the uterus is naturally driven by estradiol and female sexual behaviour is naturally stimulated by the actions of estradiol in the hypothalamus of the brain. Accordingly, this new scintillation counter is critical for our research identifying the chemical nature of important reproductive pheromones. A new scintillation counter will also help this laboratory's ability to measure steroids in blood, urine, and other media, as it will allow us to use sensitive radioimmunoassay procedures. This counter is critical for the continuation of the research of students already in the laboratory, and it will help future students to conduct innovative research in pheromone dynamics and endocrine disruption. It will help to ensure that this laboratory remains competitive, making substantial contributions to basic reproductive science and reproductive toxicology.