Endocrine glands release hormones into the bloodstream.

Endocrine glands include the:

• Adrenal
• Hypothalamus
• Islets of Langerhans in the pancreas
• Ovaries
• Parathyroid
• Pineal
• Pituitary
• Testes
• Thyroid

When a gland releases a substance, it is called secretion. Hypersecretion is when too many hormones are released. Hyposecretion is when too few hormones are released.

Many different disorders can result when too few hormones or too many hormones are released.

Here is a partial list of disorders that may result when a particular gland does not produce the right amount of hormones.

Adrenal:

• Addison's disease
• Adrenogenital syndrome
• Cushing syndrome
• Pheochromocytoma

Pancreas:

• Diabetes
• Hypoglycemia

Parathyroid:

• Tetany
• Renal calculi
• Excessive loss of minerals from bone

Pituitary:

• Dwarfism
• Acromegaly
• Diabetes
• Gigantism
• Diabetes insipidus

Testes and ovaries:

• Lack of sex development (unclear genitalia)

Thyroid:

• Congenital hypothyroidism
• Myxedema
• Goiter
• Thyrotoxicosis

Ojeda SR, Griffin JF. Organization of the endocrine system. In: Griffin JE, Ojeda SR. Textbook of Endocrine Physiology. New York, NY: Oxford University Press; 2004:1-16.