Quantitative Changes in Macrophage Distribution in Normal Mouse Ovary Over the Course of the Estrous Cycle Examined With an Image Analysis System

Abstract

Macrophages were present in the mouse ovary over the course of the estrous cycle. The greatest numbers of macrophages appearing in corpora lutea and in atretic follicles suggest a role for macrophages in corpus luteum differentiation and follicular atresia. Their patterns of distribution at proestrus and metestrus within microenvironmental compartments suggests a functional correlation with the events of ovarian development.

In vitro production of bovine embryos: cumulus/granulosa cell gene expression patterns point to early atresia as beneficial for oocyte competence

“…We speculate that immune system activation is related to late atresia whereas the early atresia has not yet activated this type of response. This is partially confirmed by previous studies in human, where immune cells and, in particular, macrophages are abundantly recruited within the follicles at an advanced stage of atresia (Petrovská et al, 1996;Takaya et al, 1997;Gaytan et al, 1998). Again, this speculation supports the notion that early atresia, but not late atresia, is positively correlated with good IVP outcome.…”

Ovarian Follicular Atresia

“…Similar observations have been made in rodents (Petrovska et al, 1996). Considering macrophages are known to eliminate dying cells and cellular debris via phagocytosis, it is thought they participate in these same activities during granulosa cell apoptosis, once follicular atresia is underway (Takaya et al, 1997).…”

Up-Regulation of Bcl-2 through ERK Phosphorylation Is Associated with Human Macrophage Survival in an Estrogen Microenvironment

“…acrophages express estrogen receptor subtypes ␣ and ␤ (1-3) and are therefore capable of responding to increase in estrogen during the follicular phase of menstrual cycle (4), at the time of exposure from exogenous sources such as phytoestrogens (5), following administration for prophylactic and therapeutic purposes (6), or during accidental exposure to estrogenic chemicals (7,8). Estrogen affects a variety of macrophage functions; for example, it can reduce accumulation of cholesteryl esters in macrophages (2), stimulate production of NO (9,10), increase arachidonic acid release (11), regulate activationrelated events (2,12), decrease monocyte adhesion to vasculature (13), enhance macrophage phagocytosis (14), and facilitate Ca 2ϩ influx (10).…”