The Effect of Laboratory Environment on the Number of GnIH Neurons in the Brains of Mice

The neuroscience of genetic variation of fertility in mice could help us understand variation in neural mechanisms as well as infertility in humans. However, studying this variation in the lab should simulate that of nature. In order to test this, we tried to find out if mice in the lab raised in environments with photoperiods simulating either winter or spring had similar GnIH neuron counts as mice reproducing in either winter or spring in the wild. Our hypothesis for this experiment was that laboratory mice in the selection line for short reproductive photoperiods would have different numbers of GnIH neurons from mice in the selection line for long photoperiods, and also that there would be no significant difference between the number of GnIH neurons of laboratory mice and wild mice. These mice have been collected from the College Woods, and immunocytochemistry runs will be done on cross-sections on their dissected brains and GnIH neurons will be counted. One potential outcome would be that the number of GnIH neurons in selection lines for laboratory mice will be significantly different from that in wild mice. If we find that there is a significant difference, we will have to reject the null hypothesis, which would be significant in showing the laboratory environment is not sufficiently simulating the environment. Knowing whether this is true or not can help us improve laboratory procedures, and that will help us get closer to understanding the role of GnIH neurons in fertility in mice and perhaps humans. The point of my summer research was mostly to practice the procedures that would be involved in this, mainly immunocytochemistry. Before looking for GnIH neurons, my goal was to do practice ICC runs with oxytocin neurons, and then do some on GnIH, and then in the fall, start ICC for the actual research.