Ml. Lopes et al., Identification of proliferating cells in chicken embryos using 5-bromo-2 '-deoxyuridine immunohistochemical detection, GENET MOL B, 23(1), 2000, pp. 149-153
Chicken embryos were incubated with BrdU, embedded in plastic resin, sectio
ned and screened immunohistochemically to identify proliferating cells in t
he neural tube and somites. Fixation in 4% paraformaldehyde for 1 h was ess
ential for detecting specific colorimetric signals of BrdU incorporation in
to cells during the S phase of the cell cycle. Transverse sections of the n
eural tube showed that the nuclei of proliferating cells (BrdU positive) ha
d a uniform and centralized distribution, whereas unstained nuclei were fou
nd only along the extremities of the neural tube, Transverse sections of di
fferentiated somites showed proliferating cells in the scleratome and derma
tome. However, no incorporation of BrdU was observed in myotomic cells, whi
ch give rise to axial skeletal muscle, In spite of their proximity, the der
matome and myotome showed marked differences in cell proliferation. The exc
ellent preservation of morphological characteristics in the embryonic tissu
es facilitated identification of variations in BrdU incorporation.