Endocrinology is the study of a strange set of organs that produce important chemicals called hormones. These are pumped directly into the bloodstream, and rapidly circulate to all parts of the system. Most of the glands produce more than one chemical. Indeed, some, such as the pituitary gland, can produce a large number. Each hormone has a specific function. The remarkable thing is that the hormones seem to know exactly where to go and what to do.
There is usually a fine balance between the activities of the various chemicals. This is all aimed at keeping the body as near to normal as possible, and functioning with the minimum amount of discomfort. Indeed, considering the huge number of chemicals involved in the function of the system, it is amazing. The endocrine glands are all largely under the control of the pituitary gland and the hypothalamus. These two areas form part of the brain. near its base, and together act as “captain of the ship.” They produce hormones that in turn govern the production and activity of other hormones produced in other regions of the body. They can have an overriding effect. They are close together, and actually the hypothalamus is the reins that check, activate and regulate the pituitary.
Although there is no direct conscious control over these glands by the individual, certain mental states, such as tensions and stresses and other psychological conditions, may indirectly influence the hypothalamus, so in a sense there is some indirect form of control.
In ordinary health the normally functioning glands pump out measured amounts of their hormones each 24 hours. Sometimes there is a so-called circadian distribution of production. This means it may vary during the 24-hour cycle of the day. In other areas it may be on a longer-term basis, such as in the ovaries of the female, where a 28-day cycle tends to occur.
In indifferent health, usually due tosome disease process, the endocrines will produce an altered amount of chemical. There may be either overactivity or underactivity of production. In turn, this will have dire repercussions on the total system. With some, it will dramatically alter the production rate of other hormones or affect general bodily function in startling ways. The most serious cause for these irregularities is when tumours (grave if these are cancerous) commence growing in the glands.
The next gland coming down from the hypothalamus and pituitary is the thyroid. This is situated in the neck at roughly the level of the Adam’s apple. It produces thyroid hormones that in turn exert powerful influences directly on the body. They also affect the other endocrine glands of the system.
Located behind the thyroid gland, and indeed deeply embedded in its back wall, are four small, rounded organs called the parathyroids. These are concerned with calcium and phosphorus metabolism. In this way they radically affect the bones, their rate of growth and general solidarity – a vital factor to normal living.
Sitting on top of the kidneys at the back of the abdominal cavity are the adrenal glands. Each consists of an outer part or cortex, and an inner part or medulla. These two sections produce important hormones. Cortisone comes from the cortex and is well-known for its vital effect on the system. It also produces hormones that affect blood pressure, and the medulla produces adrenaline, essential in giving the body its ability to cope with situations demanding “fight or flight.” The gonads are the major differentiating glands of the sexes, and are commonly called the sex glands. In females they govern the onset of the secondary sexual characteristics, and also control menstruation and the ability to become – and remain – pregnant.
In males, apart from ensuring pubertal development, the testes produce male hormone and the sperms, the male cells of reproduction.
Finally. the pancreas is located in the abdominal cavity, and its main claim to fame is in producing insulin. Deficient supplies produce a disease syndrome called diabetes mellitus, commonly known as sugar diabetes. Unless treated. many cases could quickly end fatally. But treatment can now maintain a person in near-normal health for a good long life. Generally speaking, the study of the endocrines is a very complex one.
Doctors who study this aspect of medicine usually do so in special clinics attached to major hospital units equipped with full facilities to investigate patients. Diagnosis is often difficult. Treatment is no simple matter in most cases. It usually has to be regulated very carefully. The doctors who do this are called endocrinologists. Diabetes too, although often patient-treated, must be under strict medical supervision. but it is one of the few disorders in which the patient is encouraged to take a close part in the actual administration of therapy, such as giving insulin if this is needed. The endocrines are a fascinating study and have attracted some of the best brains in medicine.
As more research is being carried out, more knowledge is being gained. Recent development of sensitive methods for detecting very small quantities of hormones in the blood have been developed. One such method is radioimmunoassay. This is opening vast new areas, for often until the doctors know more about chemical levels in the blood, diagnosis and treatment are delayed.
There are many practical repercussions from all this. For example. infertility (the inability to conceive) is an increasingly common problem in many women after they have taken the oral contraceptive pill for awhile; there are also other unknown reasons. To date treatment had been poor and relatively ineffective. But radioimmunoassay revealed that these women often have a higher-than-normal level of prolactin in their bloodstream. This is a hormone produced by the anterior lobe of the pituitary.
With this knowledge, the doctors have developed a drug called bromocriptine that effectively lowers plasma prolactin levels. The result is that many infertile women may now become pregnant – often within a few months of diagnosis – by taking bromocriptine. This is merely one indication of the value of increased knowledge in this exciting and rewarding field.
It is pointed out that many cases of endocrine disorder give rise to odd symptoms. If any of these are recognised, do not try to treat yourself. Get along to a doctor, who in turn may refer you to an endocrinologist if it appears to be warranted. Here correct diagnosis and treatment will be readily available. Home therapy, as a general rule. has no place in the treatment of endocrine disorders