低体温誘導の記憶へのリスクと可塑性- 公募研究 2018－2019
Hypothermia caused by hibernation, suspended animation, therapeutic hypothermia or cold environment has been suspected to adversely affect memory function, but the mechanisms linking body temperature and memory formation are poorly defined (Fig. 1). We discovered that activation of neurons in the preoptic area induces hypothermia and impairs fear memory. Therefore, we are investigating how the preoptic area neurons regulate the formation and consolidation of memories in the amygdala or hippocampus. We use intraperitoneal telemetry implants for the thermal detection of body temperature changes. Moreover, we determine “freezing” behavior after fear conditioning by foot shock as a measure of the memory of a traumatic event or the ability of mice to navigate in a water or radial arm maze as a measure of spatial memory. Specifically, we are investigating by using chemogenetic methods and in-vivo Ca imaging whether preoptic area neurons control fear memories in the amygdala, a well-known center in the brain for the expression of fear. We are also investigating whether the expression of fear can also be suppressed by pharmacologically or physically cooling the body of mice (e.g. hypothermia-inducing drugs or cold environment). Finally, we are investigating the risk of chemogenetic activation of preoptic area neurons or body cooling for hippocampus-dependent (i.e. spatial) memories.