Blastocyst Fluid Formation
All mammalian blastocysts undergo some expansion prior to implantation, but the amount varies between species. Blastocysts of the human, mouse, and rat display minimal volume changes, while those of the rabbit and pig undergo enormous increases. Figure 1 presents growth curves for preimplantation rabbit blastocysts. The blastocoelic cavity increases from about 70 nl on Day 4 postcoitus (p.c.) to almost 80 μl on Day 7 p.c., the day of implantation. This increase in size stems largely from fluid accumulation, although cell multiplication also occurs (Daniel, 1964). Because the blastocyst consists almost entirely of a single-cell-thick epithelium, the trophectoderm. it is ideally suited for the study of developmental aspects of epithelial solute and water movements.
KeywordsFluid Accumulation Transepithelial Electrical Resistance Ouabain Binding Toad Urinary Bladder Methionine Uptake
Unable to display preview. Download preview PDF.
- Benos, D. J., 1981a, Developmental changes in epithelial transport characteristics of preimplantation rabbit blastocysts, J. Physiol. (London), in press.Google Scholar
- Biggers, J. D., and Powers, R. D., 1979, Na transport and swelling of the mammalian blastocyst: Effect of amiloride, in: Amiloride and Epithelial Sodium Transport (A. W. Cuthbert, G. M. Fanelli, Jr., and A. Scriabine, eds.), Urban & Schwarzenberg, Munich, pp. 167–179.Google Scholar
- Biggers, J. D., Borland, R. M., and Lechene, C. P., 1978, Ouabain-sensitive fluid accumulation and ion transport by rabbit blastocysts, J. Physiol. (London) 280:319–330.Google Scholar
- Borland, R. M., and Biggers, J. D., 1981, Water permeability of the rabbit blastocyst in vitro, manuscript in preparation.Google Scholar
- Cross, M. H., 1973, Active sodium and chloride transport across the rabbit blastocoele wall, Biol. Reprod. 8:566–575.Google Scholar
- Diamond, J. M., 1977, The epithelial junction: Bridge, gate, and fence, Physiologist 20:10–18.Google Scholar
- Hills, F., James, P. S., Paterson, J. Y. F., and Smith, M. W., 1980, Delayed development of amiloride-sensitive sodium transport in lamb distal colon, J. Physiol. (London) 303:371–384.Google Scholar
- House, C. R., 1974, Water Transport in Cells and Tissues, Arnold, London.Google Scholar