In mares, the epithelium and stratum compactum have more MHC class II+ cells during estrus than during diestrus (Watson and Thomson, 1996).
The objectives of this study were to investigate the presence of MHC II+ (HLA-DP-like) cells in the cow uterus, and to determine whether there is any significant difference in their distribution between the estrus and diestrus phases of the estrous cycle.
Tissue samples were taken from the uteri of animals that were judged to be in estrus or diestrus by inspection of the ovarium (Arthur et al.
5-ppm doses have subtle effects on the number of days of diestrus or proestrus (Figure 4A, 4B), these levels failed to significantly alter the number of days in estrus (Figure 4C), the number of estrous cycles (Figure 5), or the duration of the estrous cycle (Figure 6).
LTX-diol Daily dose concentration delivered Diestrus Proestrus (ppm) (mg/kg/day) (days) (days) 0 0 [+ or -] 0 14.
Organ weights of sexually mature female offspring evaluated in diestrus are shown in Table 5.
We examined the uteri from diestrus animals microscopically for lesions/abnormalities or inflammation.
At the end of treatment, the animals were sacrificed when they were in diestrus, by rapid decapitation between 1000 and 1100 hr.
Treatment with the high dose of PFOS further reduced the number of regular cyclers to 42% and increased the number of animals in persistent diestrus from 8% in the low-dose group to 33%.
Vaginal smear data showed that Aroclor 1221 rats had fewer estrus and proestrus days than diestrus
days relative to vehicle animals, suggesting some qualitative difference in estrous cyclicity.
In rats maintained on a 12 hr light:12 hr dark cycle, wheel activity begins to increase during the night of diestrus and peaks during the night of proestrus (19-24).
However, for each subject we calculated a cyclicity estimate based on the assumption that if a subject was following a 4-day cycle over the course of the entire procedure, then approximately 50, 25, and 25% of the lavage samples should represent days of diestrus, proestrus, and estrus, respectively.