Abstract # 897 Poster # 160:

Scheduled for Friday, August 19, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation

Endometrial cycles in the vervet monkey (Cercopithecus aethiops)

O. D. Slayden, R. Carroll, J. W. Fanton, G. Maginnis and R. M. Brenner
Oregon National Primate Research Center, 505 NW 185th Ave, Beaverton, Oregon 97006, USA
     Endometrial cycles in vervets are not well studied. To evaluate endometrial function in this species, we studied cyclic endometrial patterns in either naturally cycling monkeys or artificially cycled, ovariectomized ones treated sequentially with estradiol (E) and progesterone (P). Animals were swabbed vaginally to detect menses and serum levels of E and P were measured by immunoassay. Proliferative activity was assessed by immunocytochemistry of the Ki-67 marker, and matrix metalloproteinase (MMP) expression was determined by immunocytochemistry of MMP-1,-2 and -3. Results showed that P withdrawal, during either natural or induced cycles, induced menstrual breakdown marked by upregulation of MMP-1,2 and 3 in the sloughing tissues of the functionalis zone. After menses ended, MMPs declined, and proliferation began in the functionalis in both the natural and induced follicular phase. When P levels rose, proliferation ended in the functionalis and began in the basalis zone, continuing there until the end of the cycle. In sum, in the vervet endometrium, P withdrawal induced menstrual breakdown that was accompanied by MMP expression in the sloughing zone. The functionalis proliferated during the follicular, E-dominated phase and the basalis did so during the luteal, P-dominated one. Therefore, vervets are useful model animals for studies of menstruation, the role of MMPs in endometrial remodeling, and zone-specific factors which regulate proliferation in the nonhuman primate endometrium. Supported by HD19182, HD18185 and RR00163.