Hormones deliver chemical messages throughout the body, and each hormone, or messenger, has a different function. Hormones also have a wide variety of effects on the body. Insulin, which is integral to the development and control of diabetes, is perhaps one of the most widely recognized hormones. Estrogen and progesterone, hormones that play a vital role in the female reproductive system, are also well known.
If hormones are the body’s chemical messengers, the endocrine system is the body’s post office. This system is comprised of tissue groups that distribute hormones into the bloodstream which are “addressed” to certain areas of the body. The most common type of tissue in the endocrine system is the gland. From glands, hormones are released directly into blood vessels in and around the tissue, and from there they travel on. However, there are other very important hormones that are not released from glands. For instance, the heart, liver, and kidney also release crucial hormones to the body. Additionally, there are some hormones that are “addressed” to one single tissue in the body, while others are a kind of mass mailing and affect every single cell. Because hormones only exist in the body in minute quantities, testing in laboratories must be incredibly precise in order to detect them.
Pathogenesis Of Endocrine System Disease
Each hormone in the body has a feedback system dedicated specifically to it. That system allows the body to regulate hormone levels and adjust levels where necessary. Bodily functions such as temperature, blood sugar levels, and others are kept in line by various hormones. Often times the body is kept in balance when hormones with opposite functions work together. However, when endocrine system disease develops it does so because there is either too much or not enough of a particular hormone (or hormones), or when the pathway for hormones – the messengers – is blocked somehow. Symptoms are often caused either by tissue problems, which are often the source of the hormone in question, or issues in other parts of the body where secretion and action of hormones takes place.
A common cause of endocrine system disease is a tumor or tissue growth in an endocrine gland, which can cause that gland to overproduce a certain hormone. Another reason the disease can develop is when an endocrine gland is completely destroyed for one reason or another, leading to a serious underproduction of the hormone it is responsible for producing. Overproduction, or an excess, of a particular hormone are usually termed by the prefix “hyper”. A common example is hyperthyroidism, which is an overproduction of the thyroid hormone by the thyroid gland. If a disease is caused by an underproduction, or deficiency, of a particular hormone the term used to describe it usually begins with hypo. Following the thyroid example, hypothyroidism is an underproduction of the thyroid hormone by the thyroid gland.
Much of the time an abnormal gland doesn’t just overproduce a hormone, it also fails to respond normally to the body’s feedback messages and signals. This can result in a situation where in the body produces hormones in excess when the body is really telling it to cut back on the hormone. In other cases the body produces more of a hormone than it needs because another part of the body is stimulating it to do so. For instance, a tumor from outside the endocrine system can produce substances that “look like” hormones to the body, causing the body to respond as it would were that hormone really being produced.
Diseases that are caused by an underproduction of hormones can also stem from multiple sources. For instance, autoimmune diseases or processes can destroy tissue because the body sees it as foreign, even though it’s not. When this happens the cells are destroyed. In its early stages, as the body begins to lose tissue, the body tends to overcompensate by producing more of the hormone that would normally have come from the dying tissue. This can cause a dangerous situation wherein the symptoms of the disease aren’t noticed until much later – usually not until the tissue is completely destroyed.
Tissue disruption can also be a cause for endocrine disorders involving reduced activity, or an underproduction of a particular hormone, as well. For instance, this can occur when one hormone is responsible for sending a message to produce a second type of hormone. Take the pituitary gland, for example. It secretes a hormone that tells the thyroid gland to secret its hormone. So if the levels of the first hormone are low, it can lead to an underproduction of the second hormone due to the lack of “messengers”. This can occur even if the second hormone gland – in this example, the thyroid gland – is completely healthy.
Another reason the body can experience a loss of endocrine function is that tumors may not actually produce hormones, but may compress or otherwise eliminate an endocrine gland. Furthermore, a change in the way tissues respond to hormones that have targeted them can also contribute to endocrine disease and other issues related to it. For example, type 2 diabetes mellitus is a condition that exists wherein the body produces insulin, but the cells responsible for absorbing that insulin no longer respond to it. Very frequently this condition is related to obesity.
Existing Treatments for Endocrine System Disease
Diseases of the endocrine system that are caused by an overproduction of a certain hormone are generally treated surgically (removing the tumor), via radiation (such as by using radioactive iodine to destroy a malfunctioning gland), or with medication. In cases where a hormone deficiency is present treatment usually involves replacing the missing hormone through injections, such as with insulin, or through some other process. In fact, many treatments for steroid and hormone replacement can be taken orally.
Animals that are undergoing any kind of hormone replacement treatment must be closely monitored for undesirable effects. It is also important that these animals are retested regularly to ensure they are receiving the correct dosage. Sometimes abnormally functioning glands will recover and hormone replacement can cease. This is often the case after an endocrine tumor has been removed. But most of the time endocrine system disease requires lifelong treatment.