Figure 5. Influence of low estrogen levels on mRNA levels for biglycan and decorin. A and B: Corneal tissues were collected from a cohort of 54-week-old control and OVX female rabbits. Corneal tissues were separated into peripheral and central corneal tissues by using a 6 mm biopsy punch. The mRNA levels for proteoglycans such as decorin and biglycan were determined by RT–PCR in these tissues. C and D:. A cohort of young female rabbits was either left unoperated (control) or subject to OVX at 8 weeks of age. Corneal tissues were collected from these animals at 22 and 32 weeks of age and central and peripheral corneal tissues were analyzed separately. Levels of proteoglycan mRNA were determined by RT–PCR in these tissues. Values are plotted as a percentage of decorin or biglycan mRNA levels in normal control animals. Significant changes compared with normal controls are indicated (p<=0.05, p=not significant [NS]).