Figure 4.

Mgp Cre–mediated lacZ anterior segment expression. Five-μm meridional sections from X-gal–stained eyes from 4- to 6-week-old mice counterstained with hematoxylin and eosin. Mice 1 through 4 were from different breeding pairs. Mice 4 and 5 originated from a second founder. Mouse 4 is the Mgp-lacZ double heterozygous (Mgp^Cre/+;R26R^lacZ/+) and mouse 5 is the littermate no Cre allele control (Mgp^+/+;R26R^lacZ/+). Eyes from mice 1 and 2 were stained as whole globes and embedded in Technovit plastic resin. Mice 3, 4, 5 were stained as bisected specimens and embedded in paraffin. All crosses resulted in a similar expression pattern. lacZ expression was confined to the TM region. Al layers of the TM were heavily stained with X-gal, including the Schlemm's canal inner and outer wall. High lacZ expression was also observed in the ciliary muscle and on the sclera cells above the outflow region. Original magnifications: left column: ×100, middle column: ×200, right column: ×400.