Time course of photon bioluminescence.
(A) Time course of photon bioluminescence in five groups of animals: Luc ip, luciferase-expressing mice receiving intraperitoneal injections; Luc TT, luciferase-expressing mice receiving transtympanic injections; Luc TT RW closure, luciferase-expressing mice that received transtympanic injections after round window membrane obstruction; WT ip, wild-type mice receiving intraperitoneal injections. Background, background (no photons). (B) Bar graphs showing the highest photon counts by region. ip, intraperitoneal injection; TT, transtympanic injection; RW cl/TT, transtympanic injection after round window membrane obstruction. (C) Delivery time into GFAP-expressing cells of inner ear. Average time when the signal was maximum in each group was shown (mean ± SEM). Same conventions as in Fig. 2. *p<0.05.