Meeting Abstract

P3-133    Physiological response of rodents to prolonged cold exposure Reges, C*; Schaeffer, PJ; Miami University; Miami University regescr@miamioh.edu

Heart disease is the number one cause of death globally, and one of the signs of heart disease is an enlarged heart. As it happens, an enlarged heart, also called cardiac hypertrophy, may be considered good or bad depending on who you ask. If you ask an athlete, an enlarged heart is beneficial, because the heart is more efficient and can pump more blood per pump. But if you ask a doctor, an enlarged heart is a sign that you may have heart disease. In this study, we are comparing the hearts of prairie voles in winter and in summer, because we know their left ventricle weight increases 20% in winter and returns to its original size in summer. Little is known about the cause of heart hypertrophy after prolonged cold exposure, so we want to know if the increased workload of having to stay warm in winter is good or bad for the heart. We will use loggers to look at heart rate, body temperature, and perform electrocardiograms and use histology to look for signs of fibrosis (scarring) of the heart tissue and increased heart cell size. To supplement the data collected outdoors, we will also have echocardiogram data taken from lab mice after prolonged cold exposure. This study could help determine whether this type of hypertrophy occurring in voles is more like athletes, like people with heart disease, or potentially an uncategorized form of hypertrophy, seasonal hypertrophy. We study both types of hypertrophies, to understand the fundamentals of how the heart functions in different situations, to potentially further heart disease research. We know that human mortality does increase with colder winters, so we may see negative effects due to winter on the rodents’ hearts. As some areas are experiencing more extreme winters due to the climate crisis, we can see how the winter may affect human heart health.