sebaceous glands
Last reviewed 01/2018
Sebaceous glands are simple or branched glands which develop from the external root sheath of hair follicles, or less commonly, from the epidermis directly. The latter are found in hairless regions:
- the eyelid - meibomian glands
- mucous membranes - Fordyce spots
- the nipples
- perianal region
- around genitalia
They are holocrine glands: glandular cells fill with fatty products include triglycerides, fatty acids and cholesterol, before dying and being secreted into the upper part of the follicle. The secretion, termed sebum, coats the hair and skin. It has many functions:
- weak bacteriocidal and fungistatic properties
- lubrication of skin
- waterproofing of skin
- physical protection for external auditory canal - cerumen
Sebaceous glands are stimulated by androgenic hormones. The pubertal hormonal burst predisposes the teenager to acne.