Neovascularization in the adult central nervous system occurs as a response to several pathophysiological conditions such as ischemia, wound repair, or neoplasia. Endothelial cells from different blood vessel types, different organs, and different species are heterogeneous; therefore, the appropriat
Evidence for the continuation of meiosis and spermiogenesis in in vitro cultures of spermatogenic cells fromXenopus laevis
β Scribed by Risley, Michael S. ;Eckhardt, Ronald A.
- Publisher
- John Wiley and Sons
- Year
- 1979
- Tongue
- English
- Weight
- 365 KB
- Volume
- 207
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Spermatogenic cells were obtained from Xenopus laevis testes by collagenase dissociation and subsequently separated into two fractions by density gradient centrifugation in Metrizamide and by unit gravity sedimentation in bovine serum albumin gradients. One fraction was highly enriched for primary spermatocytes while the other fraction was highly enriched for earlyβmid stage spermatids. The cells from each fraction were cultured separately in modified DNOM medium for 23 days to determine the extent to which differentiation could be maintained in vitro. Differential cell counts revealed that earlyβmid stage spermatids continues to differentiate in vitro through the stages of cytoplasmic shedding. Spermatocytes passed through both meiotic divisions throughout the 23 day period and produced spermatids which also differentiated through the cytoplasmic shedding stages. The results demonstrated that significant differentiative potential is retained by Xenopus spermatogenic cells cultured in vitro even after dissociation and cell separation procedurs.
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