Abstract
Visceral fat obesity is more strongly associated with ectopic fat deposition, lipotoxicity, and metabolic disease compared to generalized obesity. To study the function of visceral fat tissue, we describe steps to knock in or out target genes by spot injecting adeno-associated viruses (AAV) in visceral fat tissue. We provide details on anesthesia, incision, and spot injection into the epidydimal white adipose tissue (eWAT) of live anesthetized mice. Furthermore, we detail an efficient technique for expressing exogenous protein in mouse eWAT. For complete details on the use and execution of this protocol, please refer to Zhao et al. (2022).