Animal anatomy, histology, pathological anatomy

Topic: Hemosiderosis of the spleen - 2 hours

Topic objectives: To teach students the macroscopic and microscopic manifestations of dystrophy using the example of the spleen. Visual equipment and instruments: Organ, microtome, block window box, hematoksilin, eosin. Alcohol, xylene, paraffin, microscopy, histological preparation No. 19 and museum preparations

Purpose of the lesson: Study of microscopic and macroscopic appearance. 1. Working pieces of pathological material will be cut from the kidneys and skeletal muscles. 2. The particles are washed and dehydrated in an alcohol battery. 3. Paraffin blocks are made. 4. Paint normal cuts. 5. Sections are stained with hematoxylin and eosin dyes. 6. Macroscopic changes are studied using museum preparations. Hemosiderin is a yellow-brown or brown pigment. When combined with iron, it is soluble in acid. Typically, the spleen is the repository of hemosiderin and plays a key role in iron metabolism.

The spleen of horses contains more pigment than that of cattle and pigs. Hemosiderin metabolism disorders can be general or local. General hemosiderosis is observed in several pigment organs. This is due to the prolonged presence of red blood cells during hemolysis (infection and invasion). Local hemosiderosis is caused by disruption of red blood cells outside the blood vessels (hyperemia, hemorrhage).

Hemosiderosis in the liver can be either local or general.

Microscopic view: A small mirror shows brown granular pigment.

The amount and distribution of pigment varies from piece to piece. The pigment is formed and accumulates in the cytoplasm - reticuloendothelium in cells. In a large mirror, the pigment is visible in the cytoplasm of large cells, the nucleus of which resembles a blood monocyte in histocyte cells. These cells are located in capillaries inside the compartment, between the partitions. Sometimes the cytoplasm of cells is completely filled with pigment, and their nuclei are invisible. Pigmentation is sometimes found in the cytoplasm of parenchymal cells.

Macroscopic view. The liver has a denser consistency, and when cut, the surface looks nutmeg: the center of the organ is brown or dark brown, and the edges are light gray.