Endocrine System Disorders
Douglas Wilkin, Ph.D.
Jean Brainard, Ph.D.
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Printed: November 11, 2015
AUTHORS
Douglas Wilkin, Ph.D.
Jean Brainard, Ph.D.
www.ck12.org
C HAPTER
Chapter 1. Endocrine System Disorders
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Endocrine System
Disorders
• Identify general problems and diseases associated with the endocrine system.
• Compare hypersecretion to hyposecretion.
• Explain hormone resistance.
How tall can a person become?
This may be an exaggeration, but the world’s tallest person, Robert Pershing Wadlow, stood almost nine feet tall
when he died at the age of 22. Is growing that tall due to a problem with the endocrine system?
Endocrine System Disorders
Diseases of the endocrine system are relatively common. An endocrine disease usually involves the secretion of too
much or not enough hormone. When too much hormone is secreted, it is called hypersecretion. When not enough
hormone is secreted, it is called hyposecretion.
Hypersecretion
Hypersecretion by an endocrine gland is often caused by a tumor. For example, a tumor of the pituitary gland
can cause hypersecretion of growth hormone. If this occurs in childhood, it results in very long arms and legs and
abnormally tall stature by adulthood. The condition is commonly known as gigantism (see Figure 1.1). See Giants Part 1 - Pituitary Gigantism and Acromegaly at http://www.youtube.com/watch?v=Ebhf1qKVA9A for information
about pituitary giants.
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FIGURE 1.1
Hypersecretion of growth hormone leads to abnormal growth, often called
gigantism.
Hyposecretion
Destruction of hormone-secreting cells of a gland may result in not enough of a hormone being secreted. This occurs
in type 1 diabetes. In this case, the body’s own immune system attacks and destroys cells of the pancreas that secrete
insulin, making type 1 diabetes an autoimmune disease. A person with type 1 diabetes must frequently monitor the
level of glucose in the blood (see Figure 1.2). If the level of blood glucose is too high, insulin is injected to bring it
under control. If it is too low, a small amount of sugar is consumed.
FIGURE 1.2
To measure the level of glucose in the
blood, a drop of blood is placed on a test
strip, which is read by a meter.
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Chapter 1. Endocrine System Disorders
Hormone Resistance
In some cases, an endocrine gland secretes a normal amount of hormone, but target cells do not respond to the
hormone. Often, this is because target cells have become resistant to the hormone. Type 2 diabetes is an example
of this type of endocrine disorder. In type 2 diabetes, body cells do not respond to normal amounts of insulin. As a
result, cells do not take up glucose and the amount of glucose in the blood becomes too high. This type of diabetes
is usually treated with medication and diet. The addition of extra insulin to the treatment can help some patients.
Summary
• Endocrine system disorders usually involve the secretion of too much or not enough hormone. For example, a
tumor of the adrenal gland may lead to excessive secretion of growth hormone, which causes gigantism.
• In Type 1 diabetes, the pancreas does not secrete enough insulin, which causes high levels of glucose in the
blood.
Explore More
Use this resource to answer the questions that follow.
• Diseases and Conditions at http://www.hormone.org/diseases-and-conditions .
1. Describe the following endocrine disorders:
a.
b.
c.
d.
diabetes
growth hormone deficiency
osteoporosis
Polycystic Ovary Syndrome
Review
1. Define hypersecretion. Give an example of an endocrine disorder that involves hypersecretion.
2. Explain why a person with type 2 diabetes is not affected by normal amounts of insulin. Will providing extra
insulin help this person?
References
1. . Extremely tall individual . Public Domain
2. Rupali Raju. Measuring blood glucose level . CC BY-NC 3.0
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