Tissues

Hematoxylin or Eosin Stains Tissues such as the intestinal mucosa can be stained with alcoholic eosin or hematoxylin (16,17).

Fat and Lipoid Stains Fat stains are used either as differential tissue stains—for example, to outline malignant lesions infiltrating fat tissue—or to identify fat and lipids in organs or pathologic lesions.

When differential fat staining is desired, the freshly trimmed, fresh or formalin-fixed specimen is immersed in a saturated solution of Sudan III or Scharlach R in 70% alcohol (18). The fat will stain bright red. Nonfatty structures are decolorized by placing the specimen in 95% alcohol. After the differentiation is complete, the tissue is washed and mounted in formalin solution. A variant of this method (19) uses formalin-fixed specimens, which are soaked for 1 d in 50% alcohol, followed by staining for 1 or 2 d in a saturated solution of Sudan III in 70% alcohol. After the fat has become deep orange red, the specimen is returned to 50% alcohol solution until all nonfatty tissues return to their normal color.

Staining of Myelinated and Nonmyelinated Fibers of Brain These methods (20) have been largely replaced by the use of histologic macrosections. Therefore, they will not be described here.

Stain for Iron (Hemosiderin) The reaction of Fe3+ with ferrocyanide has been used most widely for the demonstration of tissue iron in hemochromatosis and other iron overload states. Slices of liver, pancreas, heart, or other tissues are placed for several minutes in a 1-5% aqueous solution of potassium ferrocyanide and then are transferred to 2% hydrochloric acid. One can also use a solution of equal parts of 10% HCl and 5% aqueous ferrocyanide (21). The specimens are then washed for 12 h in running water. In the presence of abundant hemosiderin, the tissue will rapidly turn dark blue. Mount in 5% formalin-saline. It should be noted that in hemochromatosis specimens the color tends to fade out.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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