• A normal sebaceous gland under high power.
• Towards the periphery of this single acinus of a sebaceous gland is a single layer of cuboidal cells that are somewhat deeper staining.
• Towards the center are large cells which are pale staining cytoplasm and a central pyknotic nucleus.
• At the very center is a dark staining structure that represents the duct of this gland.
• The central, light-staining cells are normally shed as such into the hair shaft and form the oily secretion that coats the hair as well as the overlying skin.
|Normal sebaceous gland|
|General Gross Description|
|General Micro Description|
•Sebaceous glands occur in most areas of the skin
closely attached to the hair follicle.
•Particular areas of skin such as the forehead and the
area around the nose are particularly rich in sebaceous
•Each gland is a fraction of a millimeter in diameter
and consists of a large round acinus attached to the
hair follicle by a very short duct.
•In cross section, the acinus has a single layer of
cuboidal cells in the periphery and large empty looking
cells with pyknotic nuclei towards the center.
•The larger cells are derived from the smaller cells by
the accumulation of lipid.
•The empty looking cells, which are in fact filled with lipid, are shed into the hair shaft and empty on to the surface of the skin to give rise to the oily secretion characteristic of these glands.
|Basic Histology: Text & Atlas, 10th Ed., 2003, Ch. 18.|