Fig. 4.

Zonal expression of putative factors implicated in HFA development and/or function. Schema shows specific zonal expression of putative factors implicated in HFA development and/or function. Black crossbar denotes high levels of expression, whereas absence of a bar represents lack of expression. Dark gray depicts moderate levels of expression, and light gray depicts low levels. LDL-R, LDL receptor; PCNA, proliferating cell nuclear antigen. Figure was derived from studies shown in right column.