Also in the section Location of the Pituitary Gland The pituitary gland is located at the base of the brain, behind the bridge of the nose. The arrow indicates the location of the pituitary gland at the base of the brain. Anatomy of the Pituitary Gland The pituitary has two lobes, the anterior and the posterior lobe.
Vasopressin is also known as antidiuretic hormone ADH. It acts on the kidney to conserve water and is important in fluid and electrolyte balance. Oxytocin stimulates the contraction of the smooth muscles of the uterus, which is important during childbirth.
Oxytocin also contracts the smooth muscle of the breast for milk production. The pituitary gland has two main parts, the anterior pituitary gland and the posterior pituitary gland. The gland is attached to a part of the brain the hypothalamus that controls its activity. The anterior pituitary gland is connected to the brain by short blood vessels. The posterior pituitary gland is actually part of the brain and it secretes hormones directly into the bloodstream under the command of the brain.
The pituitary gland is called the 'master gland' as the hormones it produces control so many different processes in the body. It senses the body's needs and sends signals to different organs and glands throughout the body to regulate their function and maintain an appropriate environment.
It secretes a variety of hormones into the bloodstream which act as messengers to transmit information from the pituitary gland to distant cells, regulating their activity. For example, the pituitary gland produces prolactin , which acts on the breasts to induce milk production.
Through secretion of its hormones, the pituitary gland controls metabolism , growth, sexual maturation, reproduction, blood pressure and many other vital physical functions and processes. Sometimes excess cerebrospinal fluid can fill the space around the pituitary gland and compress it resulting in empty sella syndrome Empty Sella Syndrome In empty sella syndrome, the sella turcica the bony structure at the base of the brain that houses the pituitary gland fills with cerebrospinal fluid, partially or completely compressing the The pressure may cause the pituitary to overproduce or underproduce hormones.
Acromegaly or gigantism Gigantism and Acromegaly Overproduction of growth hormone causes excessive growth. In children, the condition is called gigantism. In adults, it is called acromegaly.
Excessive growth hormone is almost always caused Cushing disease Cushing Syndrome In Cushing syndrome, the level of corticosteroids is excessive, usually due to taking corticosteroid drugs or overproduction by the adrenal glands. Cushing syndrome usually results from taking Galactorrhea Galactorrhea Galactorrhea is the production of breast milk in men or in women who are not breastfeeding. The most common cause of galactorrhea is overproduction of the hormone prolactin hyperprolactinemia Erectile dysfunction Erectile Dysfunction ED Erectile dysfunction ED is the inability to attain or sustain an erection satisfactory for sexual intercourse.
See also Overview of Sexual Dysfunction in Men. Every man occasionally has Infertility Overview of Infertility Infertility is usually defined as the inability of a couple to achieve a pregnancy after repeated intercourse without contraception for 1 year. Frequent intercourse without birth control usually Central diabetes insipidus Central Diabetes Insipidus Central diabetes insipidus is a lack of the hormone vasopressin antidiuretic hormone that causes excessive production of very dilute urine polyuria.
Central diabetes insipidus has several Hypopituitarism Hypopituitarism Hypopituitarism is an underactive pituitary gland that results in deficiency of one or more pituitary hormones. Symptoms of hypopituitarism depend on what hormone is deficient and may include Doctors can diagnose pituitary gland malfunction using several tests.
Imaging tests, such as a computed tomography CT or magnetic resonance imaging MRI , can show whether the pituitary has enlarged for example, if a pituitary tumor Enlargement of the Pituitary Gland Enlargement of the pituitary gland is usually due to a tumor but may be due to bleeding into the gland or involvement by some other disease, such as tuberculosis or sarcoidosis.
Such tests can usually determine whether a tumor exists in the gland. Doctors can measure the levels of pituitary hormones, usually by a simple blood test. Doctors select which pituitary hormone levels they want to measure depending on the person's symptoms. The hypothalamus releases signaling molecules that incite the anterior pituitary to produce hormones.
The posterior pituitary secretes two important endocrine hormones—oxytocin and antidiuretic hormone. The posterior pituitary or neurohypophysis comprises the posterior lobe of the pituitary gland and is part of the endocrine system. Despite its name, the posterior pituitary gland is not a gland; rather, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary gland.
The posterior pituitary consists mainly of neuronal projections axons extending from the supraoptic and paraventricular nuclei of the hypothalamus. These axons release peptide hormones into the capillaries of the hypophyseal circulation. These are then stored in neurosecretory vesicles Herring bodies before being secreted by the posterior pituitary into the systemic bloodstream.
The posterior pituitary is derived from the hypothalamus and is distinct from the more fleshy, vascularized anterior lobe. The posterior pituitary is composed of two parts:. Privacy Policy. Skip to main content. Endocrine System. Search for:. The Pituitary Gland. Overview of the Pituitary Gland The pituitary gland is connected to the hypothalamus and secretes nine hormones that regulate body homeostasis.
Learning Objectives Summarize the structure and function of the pituitary gland. Key Takeaways Key Points The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea.
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