Page 185 - Atlas of Histology with Functional Correlations

FIGURE 5.13 ■ Adipose tissue in the intestine. Stain: hematoxylin and eosin.
Medium magnification.

FUNCTIONAL CORRELATIONS 5.4 ■ Adipose

Tissue

The two distinct types of adipose tissues in the body are white adipose tissue
and brown adipose tissue. These adipose tissues represent the main sites of
lipid storage and metabolism in the body.

White Adipose Tissue (Unilocular)

White adipose tissue is the more common type. Cells of white adipose tissue,
the adipocytes, are large and store lipids as a single, large droplet

(unilocular). The stored lipids are primarily triglycerides (fatty acids and
glycerol) derived from the intestinal lipoproteins and the very-low-density
lipoproteins from the liver. This adipose tissue also exhibits a wider

distribution than brown adipose tissue. White adipose tissue is distributed
throughout the body, with the distribution pattern showing variations that are
dependent on the gender and age of the individual. In addition to serving as
an energy source, white adipose tissue provides insulation under the skin and
forms cushioning fat pads around different organs. This tissue is also highly

vascularized because of its high metabolic activity. The white adipose cells
also have receptors for insulin, glucocorticoids, growth hormone, and other
factors that influence adipose tissue to accumulate and release lipids.

Furthermore, white adipose tissue is also considered as an important
endocrine organ. These cells are the sole source of a hormone called leptin,
which increases carbohydrate and lipid metabolism in cells. This hormone
also influences cells in the hypothalamus and regulates appetite, energy

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