Fig. 2.

Markers for sprouting in response to ECL show E₂-dependent effects in wild-type but not ApoE-KO mice.A, The absolute width and OD of SYN immunoreactivity in the inner molecular layer were measured with an image-processing analysis system, and integrated density (thickness × optical density) was calculated. The y-axis gives integrated density as a percent of that for the WT, ovary-bearing (control) mice. There was a decrease in both thickness (15%; p < 0.05) and OD (35%; p < 0.05) of the inner layer of WT ovariectomized mice. E₂ replacement returned inner layer width, OD, and integrated density to control levels. ApoE-KO mice did not show any significant changes in response to E₂. Ovary-bearing apoE-KO mice showed a reduced integrated density (15%; NS) when compared with ovary-bearing controls. *Significantly different from control; p < 0.05. B, The OD of the outer molecular layer reached the threshold of image analysis software; however, the width of the outer layer was measured. They-axis gives the width of the outer molecular layer, expressed as a percent of the total molecular layer width. Although OVX did not cause a significant decrease in outer layer width in WT mice, E₂-replaced mice showed a significant increase in outer layer width. In contrast, no E₂ effect on outer molecular layer width was detected in aopE-KO mice. *Significantly different from inner layer width; p < 0.05.