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Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 

Characteristics of A spermatogonia and preleptotene spermatocytes in the vitamin A-deficient rat testis.

The proliferative activity and other characteristics of germ cells in the vitamin A-deficient (VAD) rat testis were investigated. In the VAD testis, A spermatogonia and preleptotene spermatocytes were found. The A spermatogonia in the VAD testis showed a bromodeoxyuridine (BrdU) labeling index of 6.6 +/- 1.1% and a mitotic index of 2.8 +/- 0.5%. After continuous labeling with BrdU for up to four days, the ultimate labeling index of A spermatogonia was 11.6 +/- 2.5%, which is less than expected. It is concluded that in the VAD rat testis, many of the proliferating A spermatogonia degenerate. During the first 18 h after administration of vitamin A, no increase was observed in either the labeling index or the mitotic index of the A spermatogonia. However, after 24 h the first wave of A spermatogonia in S phase was found, and the first wave in mitosis was found after 48 h. Furthermore, in the VAD testis the DNA content of most of the A spermatogonia was similar to that of Sertoli cells, i.e., 2n. It is concluded that in the VAD situation, nearly all A spermatogonia are arrested before the S phase of the A1 spermatogonia. The hypothesis is put forward that in the VAD testis, the remaining A spermatogonia are the undifferentiated spermatogonia that are unable to differentiate into A1 spermatogonia. The preleptotene spermatocytes in the VAD testis showed a BrdU labeling index of 20.3 +/- 3.5%, while the DNA content of most of these cells was between 3n and 4n.(ABSTRACT TRUNCATED AT 250 WORDS)[1]

References

  1. Characteristics of A spermatogonia and preleptotene spermatocytes in the vitamin A-deficient rat testis. van Pelt, A.M., van Dissel-Emiliani, F.M., Gaemers, I.C., van der Burg, M.J., Tanke, H.J., de Rooij, D.G. Biol. Reprod. (1995) [Pubmed]
 
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