Fig. 8.

Distribution of MMP-1 and MMP-7 in the placenta of Preg and RUPP rats. Cryosections (6 μm) of the placenta of Preg (A) and RUPP rats (B) were prepared for H&E or immunohistochemical staining using MMP-1 or MMP-7 antibodies (1:100). Because the rat placenta is large, 10−16 picture frames of sequential parts of the placental tissue section were acquired using a ×4 objective and the composite image of the whole placental tissue section was reconstituted and analyzed using ImageJ software. For MMP immunostaining, the total number of pixels in the tissue section image was first defined and the number of brown spots (pixels) was then counted and presented as a percentage of the total area (C and D). Total magnification: ×40. Bar graphs represent means ± SE; n = 4−6/group. *Measurements in RUPP rats were significantly different (P < 0.05) from the corresponding measurements in Preg rats.