Page 178 - Atlas of Histology with Functional Correlations

FIGURE 5.7 | Dense Irregular and Loose

Irregular Connective Tissue (Elastin Stain)

This figure illustrates a transition zone between loose irregular connective tissue
in the upper region and denser irregular connective tissue in the lower region of

the illustration. In addition, the tissue section has been specially prepared to
show the presence and distribution of elastic fibers mixed with the collagen
fibers in the connective tissue.

The elastic fibers (1, 7) have been selectively stained a deep blue using the
Verhoeff method. Using Van Gieson stain as a counterstain, acid fuchsin stains

collagen fibers (2, 6) red. Cellular details of fibroblasts are not obvious, but the
fibroblast nuclei (3, 5) stain deep blue. Blood vessels (4) are also present.

The characteristic features of dense irregular and loose connective tissues
become apparent with this staining technique. In dense irregular connective

tissue, the collagen fibers (6) are larger, more numerous, and more concentrated.
Elastic fibers are also larger and more numerous (7). In contrast, in the loose
connective tissue, both fiber types are smaller (1, 2) and more loosely arranged.
Fine elastic networks are seen in both types of connective tissue.

FIGURE 5.7 ■ Dense irregular and loose irregular connective tissue. Stains:

Verhoeff and Van Gieson. Medium magnification.

FIGURE 5.8 | Loose Irregular and Dense

Irregular Connective Tissue

This figure illustrates a gradual transition from loose irregular connective
tissue (5) to dense irregular connective tissue (1). Where firmer support and
more strength are required, dense irregular connective tissue with increased

177