In this study, we evaluated the effects of various hypothermic conditions (32℃), including lithium chloride treatment, on insulin-like growth factor 1 (IGF-1) gene expression in PC12 cells. The results show that short-term hypothermic treatment (<1 day) resulted in relatively higher IGF-1 gene expression than did longer-term treatment (>1 day). Repeated switching between normal temperature and hypothermia every 2 h increased IGF-1 gene expression approximately 3-4-fold. These findings indicate that hypothermia dynamically regulates IGF-1 gene expression. This study could be helpful for the development of treatment and diagnostic strategies for ischemia.