Monocytes/macrophages (EDl-positive) and differentiated macrophages (ED2-positive) were detected by immu-nohistochemistry in sections of whole ovaries from rats killed on the morning of proestrus (n = 6), the morning of estrus (n = 5), and the afternoon of estrus (n = 5). Cross sections of all corpora lutea, excluding the newly formed corpora lutea on estrus, were used for these analyses, without regard to age of the corpora lutea. Mean ± SEM numbers of luteal monocytes/macrophages (detected by the monoclonal antibody ED1) per high-power field were, respectively, 21.4 ± 2.1, 26.4 ± 4.0, and 27.9 ± 4.1 and were not significantly different among the three time points (p > 0.05; Fig. 1). Numbers of differentiated macrophages (detected by the monoclonal antibody ED2) per high-power field were, respectively, 6.4 ± 1.2, 10.9 ± 1.6, and 16.4 ± 2.5 (p < 0.05, proestrus vs. afternoon of estrus; Fig. 1). ventolin 100 mcg
MCP-1 protein detected by immunohistochemistry was differentially distributed among time points. In ovarian sections from rats killed on proestrus (n = 6), MCP-1 was present in the center of the corpora lutea, with the remainder of the structure being essentially devoid of staining (Fig. 2, A and B). In ovarian sections from rats killed on estrus (n = 10), MCP-1 was present throughout the corpora lutea, as well as in the central area of the corpora lutea, as either a diffuse staining or as a number of localized foci of staining (Fig. 2, C-F).
FIG. 1. Numbers of luteal ED1-positive (ED1+) cells and ED2-positive (ED2+) cells per high-power field in sections of whole ovary from rats killed on proestrus, estrus AM, and estrus PM (experiment 1). Different letters indicate significant differences at p < 0.05.
FIG. 2. MCP-1 staining (red color) in sections of whole ovary from rats killed on proestrus (A, B) and estrus (C-F; experiment 1). Luteal MCP-1 staining observed in ovarian sections from rats killed on proestrus was limited to a small, intense region of staining in the center of the corpus luteum (A, B), while staining on estrus varied between diffuse, widespread staining throughout the corpora lutea and localized foci of staining distributed throughout the tissue (C-F).