Abstract
The growth in volume of the epithelium and mesenchyme of the intestine and stomach was estimated in mouse embryos aged between 11.6 days after fertilization and birth, by means of a morphometric technique. The findings on the growth in volume of the stomach confirm the results obtained for the intestine: the epithelium grows faster than the mesenchyme and the retardation rate of the former exceeds that of the latter. In roughly the same period, the relative increase in volume is much greater for the epithelium of the intestine than for that of the stomach. However, the relative increase in volume of the mesenchyme of the intestine is similar to that of the gastric mesenchyme. A set of data can often be described by several regression equations, the choice of the function depending on the investigator's purpose and knowledge of the process under study. The growth data were first fitted by exponential and then by polynomial functions. Both fits permit an accurate linear representation of the results, but only the polynomial description permits the expression of properties like summation and the introduction of the beginning of the growth process into the growth equation as an additional parameter. Furthermore, while the specific growth rates given by the exponential model slow down with a constant rate of decrease, those given by the polynomial model seem to reach an exponential retardation. This is in accordance with other growth concepts formulated in the past.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Goedbloed J. F. The embryonic and postnatal growth of rat and mouse. I. The embryonic and early postnatal growth of the whole embryo. A model with exponential growth and sudden changes in growth rate. Acta Anat (Basel) 1972;82(3):305–306. [PubMed] [Google Scholar]
- Laird A. K. Dynamics of embryonic growth. Growth. 1966 Jun;30(2):263–275. [PubMed] [Google Scholar]
- Laird A. K. Dynamics of growth in tumors and in normal organisms. Natl Cancer Inst Monogr. 1969 May;30:15–28. [PubMed] [Google Scholar]
- Sbarbati R. Quantitative aspects of the embryonic growth of the intestine and stomach. J Anat. 1979 Dec;129(Pt 4):795–803. [PMC free article] [PubMed] [Google Scholar]
- WEIBEL E. R. Principles and methods for the morphometric study of the lung and other organs. Lab Invest. 1963 Feb;12:131–155. [PubMed] [Google Scholar]