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Holocrine glands are glands that secrete whole cells that have completely broken down for elimination from the body. This is unique because other forms of secretion do not decimate entire cells. Only three methods of glandular secretion exist in the human body: apocrine, merocine and holocrine. Unlike holocrine secretion, secretions from apocrine glands consist only of the cell membranes — not the whole cell. Merocrine glands secrete a combination of mucus and serum, leaving the rest of the cell intact.
Sebaceous glands are the only holocrine glands that exist in the body. They are a type of exocrine gland, which means they use ducts to transport secretions to a specific location outside the body; the prefix “exo” means “outside” or “on top of.” Since sebaceous glands are located on the epidermal layer of the skin, they transport secretions directly to the skin’s surface.
They are located parallel to hair follicles and are usually between hair follicles and the arrector pili muscles that support the follicles, allowing them to contract and tighten around the hair. Before secretion, the whole cells of the sebaceous glands first swell with lipids and other moisturizing agents. Then they break down, die and ooze out to engulf the surface of the skin.
When sebaceous glands disintegrate, they are secreted as a substance called “sebum.” This sebum, though a form of waste, is beneficial since it provides lubrication for hair follicles, reducing hair breakage and giving moisture to dry scalp and dry skin all over the body. In coating the body, the sebum discharged by holocrine glands prevents the excessive evaporation of water, thereby staving off dehydration. Adequate sebum can also allow good bacteria to thrive while serving as a buffer against malicious fungi and bacteria which tend to enter the body through dry, cracked skin. One drawback of this secretion from holocrine glands is that sebum, because it harbors good and bad bacteria, can lead to an unpleasant stench if not washed off regularly.
Holocrine glands consist of small clusters of cells called acini. Inside one acinus is a duct for secretion surrounded by three different layers of cells. The outer layer of cells, known as cuboidal cells, is never shed for secretion; neither is the second layer. Only the innermost layer of cells right next to the duct, known as centroacinar cells, are destroyed for secretion, leaving most of the acinus intact. New cells are generated to replace the shed cells.
@bythewell - I have a hormonal disorder that messes with my skin as well. I find that once I get the hormones in check, however, the holocrine glands calm down and so does my skin.
Of course, what works for me, might not work for you.
But, you might try exercise. I find that not only does it keep my weight in check (which helps with the hormones) it also makes my skin healthier in general. If I manage to go for a quick run every day or so, I break out much less.
I'm not sure if that's because the blood rushes to my face and somehow helps keep the bacteria away or what, but it works like a charm.
A good, mild cleanser also works really well, if you can find one that isn't going to upset your skin further. I use one with beeswax as a base and that seems to help a lot.
@bythewell - Yeah, unfortunately the holocrine glands are there for a reason and while there are medications that can help some people with acne, they don't tend to have very good side effects.
That said, if you have severe acne I would suggest talking to a dermatologist about it anyway. The side effects can be managed, and very bad acne can be scarring, in more than one way.
Not only do you have to deal with the physical scars, which can stick with you your whole life, but also the social scars. No matter how confident you are, having terrible skin can lead you to being depressed and anxious about social settings.
People think it's something they have to just "get over" but you know, if you can get it treated, why not take advantage?
Holocrine glands can be extremely annoying! I tend to have oily skin, and it must be because my holocrine glands work too hard and produce too much sebum.
I guess they are controlled by hormones, because I have a hormonal disorder and the doctor has told e that's why I still have breakouts even though I'm definitely not a teenager anymore.
I know that acne is when the glands and pores get blocked by too much sebum and old skin. I didn't know that sebum was actually whole cells being broken down.
I wish they would come up with a way of making them less active. I know there are some drugs you can take, but I've heard they can make your skin excessively, painfully dry so they obviously don't have the balance right yet.
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