Perinatal Changes in the Fluid and Electrolyte Content of Rat Liver

Abstract

ONE of the difficulties of providing a satisfactory description of the fluid and electrolyte content of a tissue is the choice of a reference framework to which these contents can be related^1,2. It is usually sufficient to relate the composition to the weight of the dry solids of the tissue, but in cases where some component of the dry solids may be subject to physiological variation, misleading conclusions may result from a comparison of data expressed in such terms. A striking example of variation in the composition of the dry solids is seen in the developing rat liver. Thus, recalculation of data reviewed by Shelley³ shows that in this tissue the glycogen content increases from nil to more than 40 g per 100 g of the total dry solids during the last four days of gestation, and then falls to 5 g per 100 g within the first day after birth.