Реферат на тему Steriods Essay Research Paper 2
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Steriods Essay, Research Paper
“Steroids.” It’s a familiar word with typically negative connotations, yet they have
benefits behind the drug also. No doubt you’ve heard about athletes who abuse
steroids. Or you may be all too aware of the bad side effects associated with
steroid medications. Well I?ll be talking about steroids in depth. What steroids
are composed of, development of steroids, how it was given a bad name, how it
works in the major parts of the body, and better way steroids can be used.
What are Steroids? Steroids are a class of hormones synthesized from
cholesterol. All steroids share the same basic four-ring carbon structure, but
differ in the number of carbon atoms attached to the number 17 carbon atom in
the structure, and in the manner in which hydrogen (H), oxygen (O), and the
hydroxyl (OH) groups are attached to the carbon atoms. There are various types
of steroids. For example, corticosteroids, such as prednisone or cortisone, are
anti-inflammatory, catabolic compounds that break tissue down. They are
completely different from the substances known as anabolic steroids. The term
“anabolic steroids” commonly refers to steroids which are synthetically produced,
molecularly altered derivatives (or “analogs”) of testosterone. Naturally occurring
testosterone is the primary sex hormone found in men, produced primarily by the
testes. The adrenal glands are the primary source of testosterone in women,
where testosterone is produced in a much lesser (10 to 15 times lesser) amount.
The development of anabolic steroids, which testosterone, has both
anabolic (tissue building) and androgenic (masculinizing) qualities. The anabolic
effects are primarily muscle growth. The androgenic effects are the development
of secondary male sex characteristics, such as growth of facial and body hair and
deepening tone of the voice. Obviously, the anabolic effects are desirable for
sports performance and cosmetic appearance. In fully developed adults,
especially women, the androgenic effects are not so desirable at all. By the early
1950’s, scientists were trying to isolate testosterone’s muscle building properties
without the masculinizing effects. Synthetic anabolic steroids were developed in
this pursuit. Researchers discovered that by making certain modifications to
testosterone, such as by adding or removing certain elements at specific locations
on the molecule, the resulting compound had high anabolic effects with a
substantially reduced androgenic effect. The term “anabolic” instead of
“androgenic” steroid promotes the modification of the molecular structure to
enhance tissue building and minimize masculinizing effects. (However, because
the anabolic and androgenic qualities of these substances cannot be completely
separated, some experts prefer the term “anabolic/androgenic steroids.”) It is also
quite common to see both testosterone and anabolic steroids generically referred
to as androgens. One of the pioneers in the history of anabolics was John Ziegler,
M.D., who in collaboration with the pharmaceutical manufacturer CIBA,
introduced the oral steroid Dianabol to weightlifters in 1956. By the mid 1960’s,
scientists had created many different anabolic steroids and thousands of strength
athletes were using them, even to day.
Steroids got a bad name after dramatically improving arthritis symptoms
in the 1940s, cortisone was hailed as a “miracle drug.” But problems emerged.
People taking cortisone for months in doses high enough to relieve inflammation
routinely experienced harmful side effects. Physicians now recognize that
prolonged use of corticosteroids can lead to widespread problems affecting:
Metabolism–Your body tends to accumulate fat in your abdomen, around your
face (”moon face”) and on the back of your neck. Also, levels of blood sugar
increase, sometimes leading to or worsening diabetes. Muscular weakness
develops. Bones–Formation of new bone is inhibited and calcium is lost in the
urine. Osteoporosis and, sometimes, joint damage result. Eyes–Incidence of
cataracts increases. Skin–Thinning occurs. Blood vessels near the surface of
your skin become more visible. Skin bruises more easily. Wounds heal slowly.
Blood pressure–Elevations are common. Immune system–Your body produces
fewer disease-fighting antibodies, making you more susceptible to viral, bacterial
and fungal infections. Emotions–Some people develop agitation, euphoria,
insomnia and, rarely, psychosis.
Even though all these side effects are possible with use of corticosteroids,
it’s unusual for one person to have them all. These side effects don’t occur with
birth control and estrogen medications.
Anabolic steroids work in the body when steroids are taken orally. Then
proceed through the gastrointestinal tract to the liver, where they are processed
before going into the blood; steroids injected, go directly into the blood stream.
Eventually, however, all anabolic steroids wind up in the blood stream, carried
along with thousands of other types of molecules. How anabolic steroids work to
increase muscular size and strength is best explained on a cellular level. The cells
within the tissues of our bodies have certain areas that are receptive to some
free-floating molecules within the blood. These areas are called receptor sites.
There are receptor sites with an affinity for steroid molecules in our skeletal
muscle cells, for example. A steroid molecule being carried along in the blood
enters the muscle cell by diffusion and binds to one of these receptor sites. The
connection that is formed permits the steroid molecule to deliver a cellular
message or command to the receptor site to effect certain metabolic changes
within the cell. One of these primary metabolic changes is increased protein
synthesis and nitrogen retention, leading to increased size and strength of the
skeletal muscle cell. The connection of a steroid molecule and receptor site is
fleeting: once the steroid molecule delivers its cellular command, it moves on to
other receptor sites, delivering its message over and over until it is converted into
another compound or is excreted in the urine. This capacity of androgens to be
converted into other substances by chemical reactions and enzymes within certain
tissues of the body will be extremely significant later when we discuss potential
side effects.
Anabolics also enhance size and strength through a different mechanism.
Intense training causes the body to produce increased levels of cortisol, a
catabolic substance that causes muscle tissue breakdown. Anabolics have an
anticatabolic effect; that is, they prevent the breakdown of muscle tissue by
displacing cortisol from its receptors. Consequently, recovery processes are
speeded up and injuries, including the microscopic muscle damage incurred from
heavy training, heal faster. Some authorities believe that the anticatabolic
properties of steroids may be of equal significance to the anabolic properties.
Anabolic steroids are processed by the liver. Their first pass through the
liver is unusually harsh on the liver. For this reason, even moderate short-term
administration of oral steroids can effect liver function test readings. Elevated
liver counts indicating liver stress (toxicity) have been reported in recent studies
of somewhat moderate oral anabolic steroid therapy (daily doses of 40 and 80 mg
of oxandrolone). However, these elevated liver function readings will return to
normal after cessation of a moderate, short-term steroid cycle. When I was doing
my research I couldn?t find one case to the contrary. Further, it is recognized that
intense weight training alone often causes changes in liver function tests,
including SGOT, SGPT and LDH (These terms, are something that all physicians
monitoring athletes using anabolic steroids should be familiar with). The more
serious liver problems attributed to anabolic steroid use include hepatocellular
carcinoma (liver cancer) and peliosis hepatitis (blood-filled sacs within the liver).
Anabolic Steroids and the Heart don?t really mix. Kind of like oil and
water. Through the use of steroids, there is a big cardiac risk that might be
increased by the use of steroids. It is a subject of speculation and some
controversy. High blood pressure is perhaps “one of the most exaggerated
claims” of steroid-related health risks, and remains unconfirmed despite
numerous studies (Friedl, 1993). Regarding blood lipid levels, oral steroids in
particular seem to cause a reduction in HDL (high-density lipoprotein
cholesterol) levels in some steroid users. However, changes in the blood lipid
levels now appear to begin to recover within about a month after discontinued
use, and, in fact, most studies do not report an increase in total cholesterol
(Yesalis & Cowart). Better ways are to prescribe steroids that reduce side
effects in a major way or just to use steroid that help you, if you have
inflammatory joints, corticosteriods help make the swelling go down. Despite
side effects, corticosteroid drugs remain a cornerstone of medical treatment. One
reason is their ability to control a inflammatory as I just mentioned, which helps
the process when nothing else will do. Another reason is the development of
drugs with varying strengths and lengths of action. These newer forms of
corticosteroids allow physicians to prescribe and administer the precise amount
of drugs needed for the shortest period. Better ways of using steroids reduce side
effects. New modes of administration include: Intermittent and single
doses–Doctors usually prescribe corticosteroids once a day or every other day
instead of several times a day. This allows your system a brief, yet helpful,
reprieve from the drug. An every other day regimen avoids most side effects, but
if followed for months, still increases the risk of osteoporosis. Injection–A
single injection of a corticosteroid can relieve serious poison ivy reactions or
seasonal allergies. Direct applications–For asthma, inhaled aerosol
corticosteroids reach the lungs’ surfaces directly. By this method, drugs subdue
inflammation and improve breathing without affecting other areas of your body.
Directly applying corticosteroid creams to inflamed skin is virtually risk-free.
However, continual use on large areas, such as for psoriasis, can cause problems,
including thinning of your skin and reduced production of steroid hormones by
your adrenal glands.
In conclusion, it can be said that, ?The side effects of steroid use appear
to be minimal.? (Di Pasquale 1990) Despite hundreds of years of development
and over fourty years of use by athletes, many of whom are now well into
middle-age, we have yet to see or hear reports of and epidemic of
steroids-related deaths. In this day and age steroids are getting more and more
popular for young teenager who want a ?Hard Body? and think they can get it
in short time by using steroids. Just think about this, think of your health in the
long run if your deciding to deal with these kind of drugs. Steroids is also
becoming a familiar word everyday, and everywhere, and I think will be around
for a very long time.
Bibliography
encarta 97
steriods law
317