In order to determine the impact of obesity on SOCE in the liver, we isolated primary hepatocytes from lean wild-type (WT) and genetically obese (Lepob/ob) mice and measured Ca2+ influx through STIM/Orai1 using the ratiometric calcium dye, Fura-2AM (Poenie and Tsien, 1986). The gene discussed is ORAI1; the disease is obesity due to melanocortin 4 receptor deficiency.