Courtesy: Medical Miracles, from Readers Digest 1981.
November.
From the frontiers of science and the far horizons of
personal courage, these stories of medical triumphs and miracles will reaffirm
your faith in the awesome powers of the human spirit. Dramatic victories and
human triumphs.
Selected and edited by the editors of Readers Digest
Events that take place when a dog wags its tail, a baby
toddles across the floor or you scratch your nose with your forefinger dwarf in
complexity the workings of a hydrogen bomb.
All are examples of muscular contraction—so commonplace we pay it no
heed, yet so mysterious that it has baffled the most gifted scientists.
More than half of the human body is muscle—“the most remarkable
stuff in nature’s curiosity shop,” as one scientist had said. From birth to death, muscles play a critical
role in everything we do. They propel us
into the world in the first place—when the womb suddenly empties itself. They provide nearly all our internal
heat. They push food along the digestive
tract, suck air into lungs, and squeeze tears from lachrymal glands. And finis is written for fails and us when
the heart muscle, after beating two and half billion times in a 70-year life
span, flatters.
We speak of “muscles of iron.” Yet the working or contractile element in
muscle is a soft jelly. How this jelly
contracts to lift 1000 times its own weight is one of the supreme miracles of
the universe. An elaborate series of
chemical and electrical events, which would require hours of days to duplicate
in the laboratory, occurs almost instantaneously when a muscle contract—the
twitch of an eyelids, for example.
There are three types of muscle in the human body. One is the striated muscle, which looks like
a sheaf of hair-sized filaments. These
are the muscles of motion—that propel us when we walk, that lift a forkful of
food, that nod our heads. Next come the
“smooth” muscles. These control such
involuntary actions as the churning of intestines during digestion, the
dilation of the pupil. A third type is
found in the heart. In structure, it is
midway between the other two. All types
of muscle are startlingly efficient machines for converting chemical energy
[food] into mechanical energy [work].
Hundreds of books and scientific papers have been written on
muscles—but none explains fully the process by which muscles contract, how you
wiggle a tow. “It is essential that we
understand these puzzles,” said Dr. Albert Szent-Gyorgyi, Nobel Prize winner
and scientific director of the National Faundation for Cancer Research. “In one was or another, failure of muscles to
contract porperly accounts for the vast majority of deaths—from heart failure,
high blood pressure and other diseases.”
It is the riddles such as these that Dr. Szent-Gyorgyi and
his co-workers went years seeking to solve.
Fiber by fiber and molecule by molecule they have taken muscles apart,
and then fitted them together again trying to discover the mechanics of
muscular action.
Research suggests that muscle is never thoroughly
relaxed. Because it is partially
tensed—something like a taut spring—it is ready for almost instantaneous action
when an electrical message from the brain orders it to contract.
Twp proteins, Dr. Szent-Gyorgye has found, are mainly
responsible for the contraction—actin and myosin. Alone, neither is contractile. But when an electrical impulse from the brain
orders the batting of an eye, or the wrinkling of a nose, actin and myosin
combine to form actomyosin, which is contractile.
In a sense of actomyosin is the muscular ‘engine.’ Its fuel is a remarkable chemical substance,
adenosine triphosphate—ATP for short.
ATP is a submicroscopic bombshell of energy. Actomyosin fibers contract violently on
contact with it. At death, ATP
disintegrates rapidly and muscles become hard, inelastic. This is rigor mortis.
To demonstrate the critical importance of ATP, Dr. Szent
Gyorgyi stored rabbit muscles, which had been washed free of the chemical, in
freezers for periods up to a year. Taken
out, thawed and touched with ATP, the hard, brittle muscles spring to life;
once again they show the elasticity they had when they propelled a rabbit in
its hopping gait.
Creating ‘living’ tissue in the laboratory has been
something of a scientific will-o-the-wisp.
But muscle researchers have come close to it. Dr. Szent-Gyorgyi mixed jelly-like actin with
jelly-like myosin. Then, with the aid of
a tiny glass nozzle, he spun this material into gossamer filaments. Watching through a microscope, he added a
droplet of ATP to the fluid surrounding the filament. There was violent contraction! He had created artificially perhaps the most
fundamental of all life processes—muscular contraction. “It was, “he says, “the most exciting moment
of my life.”
Where are such experiments leading? They may open a new frontier of attack on
some of mankind’s greatest ills. There
is no logical reason why the human heart should beat two billions times during
a lifetime, the suddenly fail. Almost
nothing is known about the cruel crippling of muscular dystrophy; or why
muscles in blood-vessel walls should tighten to produce the misery of
hypertension; of why the uterine muscles of many women become crumply
contracted each month to cause painful distress. Once the mechanics of muscular action are
thoroughly understood, we may be at the beginning of a new biology, a new
medicine.
Meanwhile, there is a great deal all of us can do to keep
our muscles functioning well. First,
they must be promptly fed. Generally
speaking, the average diet includes all the protein needed for muscle repair,
and all the carbohydrate required for muscle fuel. But muscles can starve through lack of
exercise—witness hospital patients who eat perfectly balanced meals and get out
of the bed too weak to walk. Reason:
muscles are nourished by thousands of miles of hairline capillaries, which
transport food and carry off wastes. In
the sedentary adult, large numbers of these capillaries are collapsed, out of
business, nearly all the time. Exercise
alone can open them up and provide better muscle nutrition.
A number of studies have shown the beneficial results of
exercise on the heart muscle. A study in
London bus drivers, for example, showed that drivers, who sat all day, had far more
heart trouble than conductors, who were constantly on the move. Similar checks have shown office workers more
prone to heart disease than postal workers.
Often, muscles become unduly fatigued when required to work
at too fast a rate. One housewife rushes
at her chores and is worn out by noon, while her more leisurely sister
accomplishes just as much and finishes the day still fresh. A series of treadmill experiments tells
why. In one, subjects were paced at 140
steps a minute. Gradually speed was increased
to 280. At the doubled rate, oxygen
requirements of muscles increased eightfold supplying such demands are
fatiguing in it. All work and exercise
should be paced to get the most of our muscles.
Like all other body organs and tissues, muscles must have
rest. Millions of people sleep the
traditional eight hours, and then get up exhausted. The most likely explanation: one set of
muscles has been cramped, tensed all night—wearing out the rest of the
body. The best way to avoid this is to
become acquainted with your own muscles.
Lie quietly in bed, legs straight, and arms at the
side. Contract one set of muscles at a
time, and consciously relax them. Start
with the feet and work upward. In a
matter of minutes, real relaxation can be achieved—leading to more restful
sleep.
Overburdened or weakened muscles sometimes require
additional support. This is particularly
true of the back muscles, whose chief function is to hold the body erect. Often, low-back pain can be traced to
weakness of these muscles. Every physician has his favorite set of exercises to
provide new strength. But until
exercises are well under way, extra support is sometimes necessary. A strong extra-wide belt is useful for this
purpose.
It is best, of course, not to wait until muscles are
weakened before giving them the care and consideration they deserve. For, to a great degree, we are what our
muscles make us—sick or well, vigorous or droopy, alive or dead.
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