Identifying the molecular mechanisms through which sex steroid hormones enhance memory
The objectives of this study are to identify the neurobiological mechanisms in the brain through which sex steroid hormones enhance memory. The project will use female mice to examine which mechanisms (e.g., specific receptors and cell signaling proteins) are necessary for estrogen and progesterone to enhance the consolidation of memory for objects. Mice first undergo a surgery to remove their ovaries and implant chronic cannulae bilaterally into the hippocampus. After surgical recovery, mice are allowed to explore 2 identical objects in an open arena until they have accumulated 30 sec of object exploration. Immediately afterwards, mice receive intrahippocampal injections of estrogen, progesterone, or drugs that target specific receptors or signaing molecules. Memory is tested 48 hrs later by allowing mice to explore a familiar and a novel object. Mice who remember the familiar object spent more time exploring the novel object. After testing, brains are removed for analysis.