Cellular and vascular development in immature rat adipose tissue.
Techniques that allow the study of immature subcutaneous depots in newborn and young rats were developed utilizing a histological and histochemical approach. The temporal and spatial relationship between blood vessel development and adipocyte hypertrophy was examined in rats from large and small litters. Large numbers of small (9.8 +/- 1 micron diameter) multilocular adipocytes were present in subcutaneous depots of newborn animals. These adipocytes were intimately associated with capillaries that had lumen diameters of 4-10 microns. Adipocytes rapidly increased in size up to 30-40 microns in diameter. The development of small capillaries (2-4 microns lumen diameters) was associated with this cell hypertrophy. Lipoprotein lipase (LPL) histochemistry and ultrastructural analysis indicated that the larger capillaries may potentiate LPL-mediated cell hypertrophy. Similar analysis indicated that the development of the narrow lumen capillaries may slow the rate of LPL-mediated hypertrophy. These studies indicate that the adipose tissue capillary may play an important role in adipocyte hypertrophy and metabolism.
D000273:Adipose Tissue / Q000098:blood supply / Q000201:enzymology / Q000502:physiology*; D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002196:Capillaries / Q000648:ultrastructure; D008071:Lipoprotein Lipase / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains
D008071:Lipoprotein Lipase