Weights of individual corpora lutea for experiment 2 were remarkably consistent with those observed in experiment 1. Corpora lutea of the current cycle on proestrus averaged 1.07 ± 0.03 mg (n = 7 rats), versus 0.76 ± 0.03 mg (n = 7 rats) for regressing corpora lutea from the previous cycle on the afternoon of estrus (p < 0.001). buy cipro
MCP-1 protein detected by immunohistochemistry appeared differentially distributed among time points, as observed for whole ovarian sections in experiment 1. In sections of corpora lutea of the current cycle, MCP-1 was present almost exclusively in the center of the corpora lutea, with the remainder of the structure being essentially devoid of staining. In sections of regressing corpora lutea, MCP-1 was present throughout the corpora lutea. Again, coded slides were identified correctly as estrus or proestrus by two observers, with few misclassifications, based on intensity and distribution of MCP-1 staining.
The average weight per corpus luteum of the current cycle on proestrus was 1.08 ± 0.02 mg (n = 10 rats); for regressing corpora lutea of the previous cycle on the afternoon of estrus, the value was 0.85 ± 0.03 mg (n = 10 rats; p < 0.001).
Protein per milligram luteal tissue was not different between the corpora lutea on proestrus and corpora lutea on estrus (108.4 ± 6.0 vs. 108.8 ± 5.9 ^g/mg luteal tissue; n = 8 at each time point).
When expressed per corpus luteum, the values were 117.7 ± 6.5 vs. 92.9 ± 5.7 ^g/corpus luteum, respectively; p < 0.05.
FIG. 5. Numbers of apoptotic cells per high-power field in sections of isolated corpora lutea from rats killed on proestrus or estrus PM (experiment 2). The asterisks indicate a significant difference at p < 0.001.