Figure 1.

Dispersal of luciferin into brain, skin, and internal organs. Left: Brain slices from thalamic area of adult CMV::luc mice injected i.p. with luciferin or not injected (control). Autofluorescence of luciferin in near-UV light showed that it is distributed diffusely and not restricted to the capillaries (arrow in brightfield). Right: Bioluminescence in an overdosed fos::luc neonate (postnatal day 1) imaged for 10 minutes. (A) Dorsal and (B) ventral views of the same mouse showed transgene expression in paws, tail, ears, nose, and internal organs of the abdomen. Light from the brain was visible after first removing skin over the cranium (C) and then upper cranium itself in (D). Arrows: brain bioluminescence.