Bursting firing in ventromedial hypothalamic neurons exerts dual control of anxiety-like behavior and energy expenditure

Exposure to chronic stress induces anxiety-like behavior and metabolic changes in animals, resulting in adaptive or maladaptive responses to the stressful environment. Recent studies have indicated the dorsomedial ventromedial hypothalamus (dmVMH) as an important hub that regulates both anxiety and energy homeostasis. However, up to now, how dmVMH neurons exert dual control of chronic stress-induced anxiety and energy expenditure remains poorly understood. Here, we established a chronic-stress mouse model that induced anxiety-like behavior, reduced food consumption, and decreased energy expenditure. We found that c-fos expression increased and theta band power is higher in the dmVMH after chronic stress, and the proportion of burst firing neurons significantly increased, which was mediated by elevated expression of T-type calcium channel Cav 3.1. Optogenetically evoked burst firing of dmVMH neurons induced anxiety-like behavior, shifted the respiratory exchange ratio toward fat oxidation, and decreased food intake, while knockdown of Cav3.1 in the dmVMH had the opposite effects. Collectively, our study first revealed an important role of dmVMH burst firing in the dual regulation of anxiety-like behavior and energy expenditure, and identified Cav 3.1 as a crucial regulator of the activity of the burst firing neurons in dmVMH. These molecular and cellular level findings will advance our understanding of the chronic stress-induced emotional malfunction and energy expenditure disorders.