Morphological changes in the adipocyte during fat deposition and mobilization.

777-782 l I967* -Total lipid analyses and semiautomatic measurements of adipocyte diameter were carried out on the epididymal fat depots of rats during growth, starvation, and refeeding. Protein, glyceride, and DNA analyses were performed on isolated epididymal adipocytes from rats of differing body fatness. The fat content of the epididymal depot was a linear function of adipocyte volume between 0.5 X 10~ and 4.0 X 105ps and nonlinear thereafter. Differences in the composition of isolated adipocytes indicated that both the lipid and cytoplasmic compartments enlarged during fat storage, the former progressively overshadowing the latter. It was concluded that the quantity of intracellular fat is an important determinant of the lipid content of a depot; but the volume of an adipocyte is an imperfect measure of its contained lipid. The limitations of morphological studies in assessing structural changes in adipose tissue are discussed.