作者： Jie-Min Jia, Praveen D Chowdary, Xiaofei Gao, Bo Ci, Wenjun Li, Aditi Mulgaonkar, Erik J Plautz, Gedaa Hassan, Amit Kumar, Ann M Stowe, Shao-Hua Yang, Wei Zhou, Xiankai Sun, Bianxiao Cui & Woo-Ping Ge

Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Jie-Min Jia, Xiaofei Gao, Bo Ci & Woo-Ping Ge

Department of Chemistry, Stanford University, Stanford, California, USA.

Praveen D Chowdary & Bianxiao Cui

Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, Texas, USA.

Wenjun Li & Shao-Hua Yang

Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Aditi Mulgaonkar, Gedaa Hassan, Amit Kumar & Xiankai Sun

Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Erik J Plautz & Ann M Stowe

Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-HuaZhong University of Science and Technology, Wuhan, China.

Wei Zhou

Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Woo-Ping Ge

Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Woo-Ping Ge

Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

Woo-Ping Ge

摘要：The precise manipulation of microcirculation in mice can facilitate mechanistic studies of brain injury and repair after ischemia, but this manipulation remains a technical challenge, particularly in conscious mice. We developed a technology that uses micromagnets to induce aggregation of magnetic nanoparticles to reversibly occlude blood flow in microvessels. This allowed induction of ischemia in a specific cortical region of conscious mice of any postnatal age, including perinatal and neonatal stages, with precise spatiotemporal control but without surgical intervention of the skull or artery. When combined with longitudinal live-imaging approaches, this technology facilitated the discovery of a feature of the ischemic cascade: selective loss of smooth muscle cells in juveniles but not adults shortly after onset of ischemia and during blood reperfusion.