Common Health Issues

Endocrine Glands And Their Hormones

• By Rich Health Editorial Team
• December 29, 2023

Glands are organs that secrete and release substances essential for the proper functioning of the body. There are two types of glands: exocrine and endocrine.

 

The exocrines have ducts that carry their secretions to particular parts of the body. The salivary glands that provide the mouth with saliva and the mammary glands that produce milk belong to this group, as do the glands that produce the bile in the liver and digestive juices in the stomach.

 

Endocrine glands have no ducts and release their substances, called hormones, directly into the bloodstream. The endocrines and their hormones help to regulate such vital processes as growth, development, and reproduction as well as control the balance of salt and water in the body and the level of sugar in the blood.

 

ENDOCRINE GLANDS

The endocrine glands form a complex, interdependently system. Removal or underfunctioning of one gland may seriously affect the functioning of others. Similarly, an increase in the functioning of one will change that of the others.

 

This is one reason why it is extremely dangerous to dose oneself with hormones, glandular tissue, or glandular extract.

 

The glands that make up the endocrine system are:

 

The Pituitary Gland

About the size of a pea, this gland lies in a small hollow well within the skull, at about the level of the top of the nose. It is connected to the part of the brain called the hypothalamus, and this link gives the brain direct control over the pituitary’s hormone production.

The most important function of the pituitary is to stimulate, regulate, and coordinate the functions of certain of the other endocrines. For this reason, it is called the master gland.

 

Diseases of the pituitary gland fortunately are relatively rare. Too little pituitary secretion causes certain types of dwarfism, while too much stimulates the body to grow to gigantic proportions.

 

Pituitary tumors may press on the optic nerves, resulting in headaches and loss of vision. Another rare disease of the pituitary is diabetes insipidus, which causes excessive thirst and excessive secretion of urine.

 

In some instances, malfunction of the pituitary can be successfully treated with such medications as cortisone derivative and thyroid and sex-hormone extracts.

 

The Thyroid Gland

 

The thyroid gland is in front of the throat, below the Adam’s apple and just above the breastbone. It is U-shaped, each end of the U flaring back into a lobe that is about the size of the big toe. The thyroid’s hormonal production stimulates or affects almost every important body process, including the body’s use of oxygen.

Too much or too little of the hormone, called thyroxine, can cause serious health problems. These health problems are: 

 

Hypothyroidism

This is the name given a complete or partial deficiency of thyroid hormone. The specific reasons for the deficiency can range from a thyroid missing at birth to a lack of iodine needed for the manufacture of thyroxine.

 

A total lack of the hormone in a newborn infant because the thyroid is either missing or grossly underactive results in cretinism, a rare form of mental retardation and physical underdevelopment. Early diagnosis is vitally important, so that treatment with thyroid hormone may prevent severe retardation.

 

A partial lack of thyroid hormone in later childhood—called juvenile myxedema—will also cause physical underdevelopment if treatment is not begun with thyroid hormone, extract, or synthetic substitutes. In a fully developed adult, severe hypothyroidism—or myxedema—causes weight gain, puffy skin, excessive fatigue, dry hair and hair loss, and other serious effects. All these symptoms may be reversed by regular treatment

 

Simple Goiter

The thyroid gland needs iodine for the manufacture of thyroxine, its major hormone product. Simple goiter is a symptom of a form of hypothyroidism in which insufficient iodine is available in the system for the proper functioning of the gland.

 

In its effort to produce more thyroxine, the gland becomes enlarged; this swelling is known as goiter, and it may interfere with breathing or swallowing. A very small amount of iodine in the diet—e.g., that consumed in iodized table salt at meals—is usually sufficient to prevent goiter. Anyone with even a small goiter should consult a doctor, who can readily treat the condition.

 

Hyperthyroidism

A more serious type of neck goiter develops when the thyroid manufactures too much hormone. People with hyperthyroidism are nervous and irritable and suffer from insomnia. Heat makes them very uncomfortable. The excess secretion also produces heart palpitations that people frequently mistake for a true cardiac attack.

 

Another symptom is loss of weight—in spite of the increased hunger that usually accompanies the malady. When severe, hyperthyroidism often causes the eyes to protrude, or bulge—a condition called exophthalmic goiter.

 

For many years the only treatment for hyperthyroidism was surgery, in which up to 90 percent of the gland was removed. Today combinations of drugs can help control excessively active thyroid hormone production or, where necessary, radioactive iodine can be used to lessen activity of the gland or make it completely inactive.

 

The Parathyroid Glands

There are four parathyroid glands, a pair on, or embedded in, each side of the thyroid gland in the neck. Each parathyroid is the size of a small pea. These glands help to regulate the level of calcium in the bloodstream which, in turn, helps to control the way the muscles receive nerve impulse from the brain.

 

In parathyroid deficiency, the calcium regulation is disturbed, and the muscles become subject to spasms, a condition known as tetany. The administration of parathyroid hormone—certain synthetically manufactured compounds—or a potent vitamin D preparation will keep the calcium level normal and stop the spasms. Taking calcium is also extremely helpful in such cases.

 

The Adrenal Glands

These two glands fit like small cups, one on the top of each kidney. Each adrenal gland consists of two major parts: the cortex, or outer portion, and the medulla, or central section. The cortex, essential to life, secretes more than 30 hormones and regulates many of our metabolic processes.

The two main functions of the hormones of adrenal cortex are: (1) the control of the proper salt and water content of the body; and (2) the regulation of carbohydrate, fat, and protein metabolism. In addition, the cortex secretes sex hormones, mainly androgens, similar to those produced by the testicles.

 

Atrophy or underfunctioning of the adrenal cortex produces Addison’s disease, which results in loss of salt and water in the body. Symptoms include low blood pressure, weight loss, and general weakness. The pituitary hormone ACTH (adrenocorticotrophic hormone) stimulates secretion of certain hormones by the adrenal cortex, and can be used therapeutically if the adrenal gland is not completely atrophied.

 

The ACTH used to treat humans is derived from the pituitaries of hogs and cattle. A synthetic adrenal hormone preparation can replenish the body’s supply when the adrenal glands are diseased and unproductive.

 

Administration of these hormones may bring about favorable results in the treatment of many other diseases, including rheumatic fever, arthritis and asthma.

 

The overproduction of adrenal hormones results in Cushing’s syndrome, which causes retention of salt and water, obesity of the face and trunk, and high blood pressure.

 

The medulla of the adrenal gland produces the hormone called adrenaline, or epinephrine. The output of this hormone is immediately stepped up when one becomes angry, fearful, or excited. This state produces chemical changes that prepare the body for action.

 

The Control Centers of Body Processes

Various functions and rhythms of the body are controlled by hormones, chemical messengers produced by the endocrine glands and discharged into the bloodstream. These glands include the pituitary, thyroid, parathyroids, adrenals, islets of Langerhans, and the sex glands or gonads.

Some interaction takes place among all the endocrine glands, but only the hormones from the pituitary are able to control production of hormones in other glands. Most glands produce several types of hormones—the pituitary, for example, produces at least nine—and each type reaches its own target area in the body, no matter how far from the gland producing it

 

Hypothalamus: Controls body temperature, blood pressure, regulates hunger, thirst and sex drives. May be source of emotional reactions

Pituitary: Controls bone growth and stimulates activity in other endocrine glands

Parathyroids: Control the level of calcium in the blood

Thyroid: Controls rate of chemical processes in the body

Thymus: Controls the production of a type of infection-fighting white blood cell in children, but has no apparent action in adults.

Stomach: Produces hormones to regulate digestion

Adrenals: Control salt and water balance in the body and help to prepare it for emergencies

Islets of Langerhans: Located in the pancreas, controls the level of sugar in the blood

Kidneys: Controls the acid/alkali balance in the bloodstream

Gonad: Located in the testes of men and ovaries of women, it controls sexual development and the production of sperms or eggs