THE ENDOCRINE SYSTEM

THE ENDOCRINE SYSTEM 

The endocrine glands differ markedly in appearance and are widely separated in the body. The pituitary is a round mass about the size of a large green pea, attached by a stalk to the brain stem. The thyroid, deep in the throat, has been likened to a small oyster, though it is beefy red in color. Attached to the thyroid are the parathyroid-generally four, although there may be more or less-which somewhat resemble BB shots. 

The adrenals, rising like mushrooms from atop the kidneys, are two in number. Each consists of a core, the medulla, and a casing, the cortex. The pancreas, lying against the back wall of the abdomen, might appear at first glance to be no endocrine gland at all, since it has a duct leading into the intestine. But in the tail and elsewhere it also has a few tiny segments, called islets, which form an endocrine gland, pouring their secretions into the bloodstream. The gonads, or sex glands, consist of testes in men and ovaries in women. In addition, there are the pineal gland in the upper back part of the brain, and the thymus which is found below the thyroid in young people. and withers away.

Very little is known as yet about the pineal and thymus

 The hormones these glands send through the blood to various parts of the body act like messengers (the word hormone comes from the Greek word meaning to excite or stir up). The hormones do not actually create processes; instead they give the orders for certain processes to speed up or slow down. And the endocrine glands form an interdependent system. In a sense, they can be likened to a family in that what happens to one affects the others.

 If one gland is removed, the functioning of all others is altered. Similarly, if the functioning of one increase so its secretions increase, others are affected. This is one reason why it can be dangerous to dose oneself with a hormone, glandular tissue or extract, or whatever it may be called, (or the purpose of reducing weight, getting rid of .'X oo ",,, hair, developing the breasts, becoming more virile, or for any other reason. 

As an example of how the glands work together, the pituitary secretes a hormone that moves through the blood to the adrenals to stimulate the latter. In turn, the adrenals secrete a hormone that travels to the pituitary and signals the latter to slow production of the adrenal-arousing hormone. Actually, the pituitary secretes hormones to stir up each of the other endocrine glands, and each gland responds in the same way. Until recently, it was thought that the pituitary was the "master" gland. But it is now evident that the pituitary is no all-powerful monarch on its own. It is connected to the floor of one of the ventricles in the brain called the hypothalamus. 

Heart and Blood circulatory system protective care

 PROTECTIVE CARE There is much you can do to guard the health of your heart and circulatory system. Contrary to what many people believe, the heart is a tough rather than delicate organ. Surgeons have successfully closed stab and other wounds of the heart; they have repaired the valves within the heart and corrected malformations. Protected by the tough ribs, the over- lying lungs, and its own surrounding membrane, the heart is rarely dam- aged by a blow. This fact should be reassuring to parents of football players, boxers, and other athletes. Guarding the health of the heart does not mean trying unduly to spare it.

Heart that a practice now accepted as a safeguard-a gradual return, after an actual heart attack, to active, even strenuous exercise-would, only a decade ago, have been considered medical malpractice if a doctor had prescribed it. Today, many cardiologists advise patients after heart attacks to get moving-to begin slowly, with extreme caution, gradually increasing their activity. With a gradual, well-tailored, well-supervised program, there is little or no danger of overstraining the heart. Many ex-heart cripples now are even playing strenuous games such as handball. It is now realized that such slow, gradual, progressive physical training can help the heart develop an increased network of blood-supplying vessels, sometimes a greater network than it may have had before the heart attack, and there is increasing evidence that such training may substantially reduce the risk of another attack. However, there are limits to the amount of strain that should be placed on a middle-aged, old, or damaged heart, particularly sudden strain. If you have been leading a sedentary existence, and now, wisely, you decide you need to increase your physical activity and overall physical fitness, you should by all means check with your physician first and, with his guidance, based on the health of your heart and whole circulatory system, map out a program which will lead gradually to your goal. 

Physical Excercises and Benefits

Excercises and benefits 

The person who gives proper attention to exercise and other physical activity can expect to derive a long list of benefits. Muscles, of course, if they have been weak and sagging, they will become strong. 50 will the heart, and the lungs and circulatory system. Along with strength, there will be increased endurance, coordination, and joint flexibility, and there may well be a reduction of minor aches and pain. Postural defects, too, tension and chronic tiredness are among the most common in plants today. 

There may, of course, in some instances be an actual illness to account for them.

But in many people the cause lays “gradual deterioration of the body for lack of enough physical activity. The human body, it has been observed, is capable of generating 14 horsepower with maximum effort; it generates only 0.1 horsepower at rest. In many of us who lead sedentary lives, there is some muscular atrophy, or wasting away; we become under muscled for our weight, and o we may lack the strength and endurance needed even for our sedentary jobs. 

But, in addition, it may well be that in many who lead sedentary lives, the unused horsepower, so to speak, goes into the building up of tension, with the tension then becoming a factor in producing fatigue and, sometimes, other complaints as well.

Physicians encounter many cases like that of a relatively young man, in his late thirties, who had moved along well in his career and should have been happy and at the height of his powers. Instead, he complained of chronic fatigue, sleeping problems, growing difficulty in concentrating effectively and handling work he once would handle with little effort. He suffered from frequent headaches and many vague complaints that made him feel constantly under par. 

Tests disclosed no underlying disease process. And the prescription given to him by his physician involved no medication of any kind, only a program of activity, of regular exercise beginning at a leisurely pace and progressing gradually, and of sports. Within a few months, he was sleeping well, feeling vigorous and relaxed, and turning out better work in less time, finding time to have more fun, as he put it, than he had had since his college days.