Electron microscopic study of the differentiation of rat white subcutaneous adipocytes in situ.
In the present study we investigated the process of differentiation of rat subcutaneous white adipocytes in situ using electron microscopy.


METHODS
Rat fetuses (Wistar rat) at 15 - 21 days of pregnancy were used. Sections of the subcutaneous tissue of a hind leg were prepared for examination with transmission electron microscopy by routine techniques.


RESULTS
The electron microscopic study showed that the embryonal differentiation of rat subcutaneous white adipose cells in situ started on the 15 - 16th day of gestation and was expressed by lipid accumulation and concomitant changes in the cell organelles. We observed the following in the differentiating adipocytes: 1. abundant glycogen granules; 2. appearance and accumulation of lipid droplets with gradual formation of several lipid droplets or one large lipid drop which pushed the nucleus to the periphery and rounded the cell; 3. large elongated mitochondria with densely packed transverse cristae; disintegration of cristae, swelling and vacuolization occurring in some of the mitochondria; 4. well developed endoplasmic reticulum with elongated and dilated cisternae; the initial predominance of rough endoplasmatic reticulum being superseded by prevalence of smooth endoplasmatic reticulum. The ultrastructural analysis we did revealed the consecutive stages in the adipocyte differentiation and the formation of adipocyte phenotype during the embryonal development of the rat.
Atanassova
Pepa K
PK
Department of Histology and Embryology, Medical University, Plovdiv, Bulgaria.
D017667:Adipocytes / Q000166:cytology* / Q000648:ultrastructure; D000273:Adipose Tissue / Q000166:cytology* / Q000196:embryology / Q000648:ultrastructure; D000818:Animals; D002454:Cell Differentiation; D005333:Fetus; D005865:Gestational Age; D008854:Microscopy, Electron; D051381:Rats; D017208:Rats, Wistar