In Vivo Bioluminescence Imaging of Mice

GAP43 transgenic mice were anesthetized with 2% isoflurane in 100% oxygen in an induction chamber, and injected intrapretioneally (i.p.) with different luciferase substrates on consecutive days: VivoGlo (VivoGlo Caspase 3/7 Substrate; Z-DEVD-Aminoluciferin Sodium Salt, Promega, Madison, WI, USA) followed by luciferin (XenoLight D-Luciferin - K+ Salt Bioluminescent Substrate, PerkinElmer, Waltham, MA, USA), 24 hours after^{4 (link),13 (link)}. Animals were individually placed in the heated light-tight imaging chamber of IVIS SPECTRUM Imaging System (PerkinElmer, Waltham, MA, USA) with continuous inhalation anaesthesia of 2% isoflurane–oxygen mixture at 1 L/min. To obtain the baseline values, imaging was done 3 days before the surgery and then 3, 7, 14, and 28 days after tMCAO. Total flux of photons was measured using the Living Image 4.3 acquisition and imaging software (PerkinElmer, Waltham, MA, USA), as described previously^{13 (link)}.