One of the hallmarks of reactive crypts is a base-to-surface epithelial maturation gradient in which phenotypically immature, mitotically active, basal colonocytes differentiate into mature surface cells featuring small, normochromatic
nuclei, distinct absorptive and goblet cell phenotypes, and absent mitoses (Figure 2, A through D).
To access the possible toxic effects of the treatments on erythropoisis percentage of polychromatic erythrocytes (PCE) was evaluated over 1000 total erythrocytes (PCE+NCE) (NCE = Normochromatic
The National Toxicology Program (NTP) report, 2007 showed that soluble chromate administered orally through drinking water induced a concentration-dependent increase in micronuclei in normochromatic
erythrocytes in am3-C57BL/6 male mice but only a small increase in micronuclei in [B6C3F.
The following parameters were analyzed in each specimen: a) the frequency of PCE among the first 100 NCE observed in each slide (PCE/NCE ratio); b) the frequency of micronucleated polychromatic erythrocytes (MNPCE) within 2,000 polychromatic erythrocytes counted; c) the frequency of micronucleated normochromatic
erythrocytes (MNNCE) within 2,000 normochromatic
erythrocytes counted; d) the frequency of dead cells (DC; erythrocytes with [is greater than] 3 micronuclei in the bone marrow) within 2,000 cells; e) the frequency of micronucleated peripheral blood erythrocytes (MNPBE) within 4,000 erythrocytes; f) the frequency of metaphases among 2,000 cells (MI); and g) the frequencies of cells with chromosome aberrations among 100 metaphases.
They typically display small, centrally placed, normochromatic
, round to oval nuclei with small nucleoli, slight atypia, and sparse mitotic activity (Figures 2 and 3).