AJP - Regulatory, Integrative and Comparative Physiology, Vol 257, Issue 4 732-R737, Copyright © 1989 by American Physiological Society
Changes in uterine fluid composition and acid-base status during shell formation in the chicken
Z. Arad, U. Eylath, M. Ginsburg and H. Eyal-Giladi
Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
The aim of this study was to characterize the dynamic changes in uterine
fluid composition and acid-base status during shell calcification in the
chicken. Uterine eggs at timed intervals were manually aborted and the
accompanying fluid collected and analyzed for composition of osmolytes,
enzymes, and acid-base parameters. Blood samples were analyzed for
comparison. No considerable change in blood gases took place in relation to
residence time of the calcifying egg in the uterus. A significant acidosis
occurred at latter stages. Only minor changes were revealed in plasma
osmotic and biochemical composition throughout egg calcification. In
contrast, major changes were revealed in uterine fluid composition and
acid-base status during calcification. The most prominent phenomenon was
the sharp increase in CO2 partial pressure, from 82.2 Torr at 0 h to 132.8
Torr at 10 h. As bicarbonate concentration remained almost stable, fluid pH
dropped from 7.412 to 7.250 within this stage. Uterine fluid sodium and
chloride concentrations and osmolality dropped significantly in the course
of calcification, whereas potassium concentration significantly increased.
A sharp increase in glucose, calcium, and magnesium concentrations was
measured in the early stages of calcification. These findings are discussed
in relation to existing models for transport mechanisms of the uterine
epithelial tissue. The comprehensive picture that emerges from the present
study should enable future application in establishing a self-contained
culturing system in vitro for studies of embryonic development.
