Vol. 3, # 38

October 7, 2006

 

Q:  I suffer from hypertension. What can I do to lower my blood presure naturally?- Layperson

 

A:  Blood pressure is the pressure exerted by the blood on the walls of the blood vessels. Unless indicated otherwise, blood pressure refers to systemic arterial blood pressure, i.e., the pressure in the large arteries delivering blood to body parts other than the lungs, such as the brachial artery (in the arm). The pressure of the blood in other vessels is lower than the arterial pressure. Blood pressure values are universally stated in millimetres of mercury (mmHg). The systolic pressure is defined as the peak pressure in the arteries during the cardiac cycle; the diastolic pressure is the lowest pressure (at the resting phase of the cardiac cycle). The mean arterial pressure and pulse pressure are other important quantities.

Typical values for a resting, healthy adult human are approximately 120 mmHg systolic and 80 mmHg diastolic (written as 120/80 mmHg), with large individual variations. These measures of blood pressure are not static, but undergo natural variations from one heartbeat to another or throughout the day (in a circadian rhythm); they also change in response to stress, nutritional factors, drugs, or disease.

Normal values of blood pressure

Normal ranges for blood pressure in adult humans are:

• Systolic between 90 and 135 mmHg (90–135 Torr, 12–18 kPa)
• Diastolic between 50 and 90 mmHg (50–90 Torr, 7–12 kPa)

In children the observed normal ranges are lower; in the elderly, they are often higher, largely because of reduced flexibility of the arteries. Clinical trials demonstrate that people who maintain blood pressures at the low end of these pressure ranges have much better long term cardiovascular health and are considered optimal. The principal medical debate is the aggressiveness and relative value of methods used to lower pressures into this range for those who don't maintain such pressure on their own. Elevations, more commonly seen in older people, though often considered normal, are associated with increased morbidity and mortality. The clear trend from double blind clinical trials (for the better strategies and agents) has increasingly been that lower BP is found to result in less disease.

In veterinary medicine, blood pressure values for dogs and cats are:

• Systolic between 150 and 150 mmHg
• Diastolic between 50 and 110 mmHg

Physiology

The mean arterial pressure (MAP) or mean blood pressure in the arteries supplying the body is a result of the heart pumping blood from the veins back into the arteries.

Main article: Mean arterial pressure

The up and down fluctuation of the arterial blood pressure results from the pulsatile nature of the cardiac output. The pulse pressure is determined by the interaction of the stroke volume versus the volume and elasticity of the major arteries.

The larger arteries, including all large enough to see without magnification, are low resistance (assuming no advanced atherosclerotic changes) conduits with high flow rates that generate only small drops in pressure. For instance, with a subject in the supine position, blood traveling from the heart to the toes typically only experiences a 5-mmHg drop in mean pressure.

Regulation of blood pressure

The endogenous regulation of blood pressure is not completely understood. Currently, three mechanisms of regulating blood pressure have been well-characterized:

• Baroreceptor reflex: Baroreceptors in various organs can detect changes in blood pressure, and adjust the mean arterial pressure by altering both the force and speed of the heart's contractions, as well as the total peripheral resistance.

• Renin-angiotensin system (RAS): This system is generally known for its long-term adjustment of blood pressure. This system allows the kidney to compensate for loss in blood volume or drops in blood pressure by activating an endogenous vasoconstrictor known as angiotensin II.

• Aldosterone release: This steroid hormone is released from the adrenal cortex in response to angiotensin II or high serum potassium levels. Aldosterone stimulates sodium retention and potassium excretion by the kidneys. Since sodium is the main ion that determines the amount of fluid in the blood vessels by osmosis, aldosterone will increase fluid retention, and indirectly, blood pressure.

These different mechanisms are not necessarily independent of each other, as indicated by the link between the RAS and aldosterone release. Currently, the RAS system is targeted pharmacologically by ACE inhibitors and angiotensin II receptor antagonists. The aldosterone system is directly targeted by spironolactone, an aldosterone antagonist. The fluid retention may be targeted by diuretics; however, the antihypertensive effect of diuretics is not due to its effect on blood volume. Generally, the baroreceptor reflex is not targeted in hypertension because if blocked, individuals may suffer from orthostatic hypotension and suffer from fainting.

Hemoglobin, the familiar oxygen-carrying molecule in red blood cells, may have been leading a double life. A group at the Duke University Medical Center reported in the 21 March issue of Nature that, alongside the familiar respiratory cycle, hemoglobin carries out a second cycle in which it sops up a form of nitric oxide in the lungs and releases it in blood vessels--a shuttle service that helps stabilize blood pressure. Besides giving hemoglobin a surprising new role, the finding could be a boon for efforts to turn cell-free hemoglobin solutions, which now tend to produce dangerous rises in blood pressure, into workable blood substitutes.

Researchers have found that deleting a component of a protein found in smooth muscle cells that surround the arteries can cause a dangerous and prolonged increase in blood pressure. The researchers believe that defects in this ion channel protein may underlie some forms of hereditary hypertension, thereby making the channel an attractive target for new types of blood pressure medications.

Calcium and potassium ions play important roles in regulating blood pressure. In the smooth muscle cells surrounding arteries, calcium-activated BK ion channels control the flow of potassium out of smooth muscle. When a burst of calcium is released within smooth muscle cells, the BK channels in those cells open, potassium floods out, the smooth muscle relaxes and blood pressure is lowered. But calcium can also induce blood vessel constriction, and cause high blood pressure, so researchers wanted to understand more about how these important channels are regulated.

“Some forms of inherited hypertension so far have not been pinpointed to specific genes, so these findings suggest that this is a good candidate gene to examine to see if humans with hypertension have mutations in this gene.”

"BK channels have been known for quite some time as important in blood pressure regulation," said Howard Hughes Medical Institute investigator Richard W. Aldrich, who is at Stanford University. "However, calcium has a paradoxical effect. It not only acts on these channels to produce arterial dilation, but it can also act on the contractile machinery, which leads to blood vessel constriction. Thus, there's a balance involved in regulating blood pressure, and we are hoping to learn how the BK channel acts to tip that balance toward dilation."

BK channels are found in many types of cells, including neurons, smooth muscle cells and skeletal muscle cells. The diversity of cell types that contain BK channels is matched by the architectural diversity exhibited by the building blocks, or subunits, that compose these channels. For example, earlier studies had shown that the various tissue-specific BK channels had only one basic type of a subunit, but each had a slightly different ß subunit. The difference in the ß subunit may allow BK channels from different types of tissue to respond differently to calcium and voltage signals, says Aldrich.

In a research article published in the October 19, 2000, Nature , Aldrich, Mark T. Nelson of the University of Vermont, and their colleagues created knockout mice that were missing the ß1 subunit of the BK channel that is contained in smooth muscles cells. By knocking out the gene for the ß1 subunit in mice, they targeted the properties of BK channels in smooth muscle without affecting the channels in skeletal muscle or other tissues. The mice lacking the ß1 subunit displayed high blood pressure and other abnormalities caused by prolonged hypertension.

In looking closer at the smooth muscle cells of the knockout mice, the scientists found that the BK channels in those cells showed reduced sensitivity to calcium and were unable to be opened by a drug that interacts with the ß1 subunit. The studies also revealed that the BK channels of the knockout mice were much less able to open in response to calcium release.

Physiological studies of the ß1-subunit-knockout mice revealed that their arterial blood pressure was chronically elevated and they had enlarged hearts, like humans with chronic hypertension. "The finding of elevated blood pressure was important because it showed us that the pressure regulatory system was as simple as we had predicted it to be," said Aldrich.

Altering the ß1 subunit showed such straightforward physiological effects that the subunit may be a promising target for new anti-hypertension drugs. "These findings suggest that drugs that change ß1 subunit function by altering the channel's calcium sensitivity could allow control of blood pressure up or down with fewer side effects than current treatments," he said.

The ß1 subunit's effects on calcium sensitivity offers a new model for researchers who are investigating the molecular basis of hypertension, said Aldrich. "Since we can alter this subunit to affect blood pressure without affecting other systems, we can use it as a model to study hypertension beginning at the molecular level, through cellular physiology and to the pathology and long-term ramifications of hypertension," he said.

Finally, the effects produced by knocking out the ß1 subunit gene suggest that the gene may be involved in inherited forms of hypertension, he said. "Some forms of inherited hypertension so far have not been pinpointed to specific genes, so these findings suggest that this is a good candidate gene to examine to see if humans with hypertension have mutations in this gene," said Aldrich.

Further studies of the various ß subunits will also reveal how they function in different tissues. "The organizing principle with these subunits is that they act to fine-tune the BK channels to function in specific tissues," said Aldrich. "For example, studying BK channels in neurons might reveal how the channels limit the duration of neurotransmitter release in controlling nerve impulses."

Pathophysiology

Effects of high blood pressure

Main article: Hypertension

Blood pressure exceeding normal values is called arterial hypertension. It itself is only rarely an acute problem. But because of its long-term indirect effects (and also as an indicator of other problems) it is a serious worry to physicians diagnosing it.

All level of blood pressure puts mechanical stress on the arterial walls. Higher pressures increase heart workload and progression of unhealthy tissue growth (atheroma) that develops within the walls of arteries. The higher the pressure, the more stress that is present and the more atheroma tend to progress and the heart muscle tends to thicken, enlarge and become weaker over time.

Persistent hypertension is one of the risk factors for strokes, heart attacks, heart failure, arterial aneurysms, and is the second leading cause of chronic renal failure after diabetes mellitus.

In the past, most attention was paid to diastolic pressure; but nowadays it is recognised that both high systolic pressure and high pulse pressure (the numerical difference between systolic and diastolic pressures) are also risk factors. In some cases, it appears that a decrease in excessive diastolic pressure can actually increase risk, due probably to the increased difference between systolic and diastolic pressures.

Effects of low blood pressure

Main article: Hypotension

Blood pressure that is too low is known as hypotension. The similarity in pronunciation with hypertension can cause confusion.

Low blood pressure may be a sign of severe disease and requires urgent medical attention.

When blood pressure and blood flow decrease beyond a certain point, the perfusion of the brain becomes critically decreased (i.e., the blood supply is not sufficient), causing lightheadedness, dizziness, weakness and fainting.

However, people who function well while maintaining low blood pressures have lower rates of cardiovascular disease events than people with normal blood pressures.

Factors influencing blood pressure

The physics of the circulatory system, as of any fluid system, are very complex. That said, there are many physical factors that influence blood pressure. Each of these may in turn be influenced by physiological factors, such as diet, exercise, disease, drugs, and alcohol etc.

Some physical factors are:

• Rate of pumping. In the circulatory system, this rate is called heart rate, the rate at which blood (the fluid) is pumped by the heart. The higher the heart rate, the higher (potentially, assuming no change in stroke volume) the blood pressure.
• Volume of fluid. In the case of the circulatory system, this is blood volume, the amount of blood present in the body. The more blood present in the body, the higher the rate of blood return to the heart and the resulting cardiac output. There is some relationship between dietary salt intake and increased blood volume, potentially resulting in higher blood pressure, though this varies with the individual and is highly dependent on autonomic nervous system response.
• In cardiac physiology, the rate and volume of flow are accounted for in a combined fashion by cardiac output, which is the heart rate, the rate of contraction, multiplied by the stroke volume, the amount of blood pumped out from the heart with each contraction. It represents the efficiency with which the heart circulates blood throughout the body.
• Resistance. In the circulatory system, this is the resistance of the blood vessels. The higher the resistance, the higher the blood pressure. Resistance is related to size (The larger the blood vessel, the lower the resistance), as well as the smoothness of the blood vessel walls. Smoothness is reduced by the buildup of fatty deposits on the arterial walls. Substances called vasoconstrictors can reduce the size of blood vessels, thereby increasing blood pressure. Vasodilators (such as nitroglycerin) increase the size of blood vessels, thereby decreasing blood pressure.
• Viscosity, or thickness of the fluid. If the blood gets thicker, the result is an increase in blood pressure. Certain medical conditions can change the viscosity of the blood. For instance, low red blood cell concentration, anemia, reduces viscosity, whereas increased red blood cell concentration increases viscosity. Viscosity also increases with blood sugar concentration—visualise pumping syrup. It had been thought that aspirin and related "blood thinner" drugs decreased the viscosity of blood, but studies found that they act by reducing the tendency of the blood to clot instead.

In practice, each individual's autonomic nervous system responds to and regulates all these interacting factors so that, although the above issues are important, the actual blood pressure response of a given individual varies widely because of both split-second and slow-moving responses of the nervous system and end organs. These responses are very effective in changing the variables and resulting blood pressure from moment to moment.

Other causes of low blood pressure

Sometimes the blood pressure drops significantly when a patient stands up from sitting. This is known as orthostatic hypotension; gravity reduces the rate of blood return from the body veins below the heart back to the heart, thus reducing stroke volume and cardiac output.

When people are healthy, they quickly constrict the veins below the heart and increase their heart rate to minimize and compensate for the gravity effect. This is carried out involuntarily by the autonomic nervous system. The system usually requires a few seconds to fully adjust and if the compensations are too slow or inadequate, the individual will suffer reduced blood flow to the brain, dizziness and potential blackout. Increases in G-loading, such as routinely experienced by supersonic jet pilots "pulling Gs", greatly increases this effect. Repositioning the body perpendicular to gravity largely eliminates the problem.

Other causes of low blood pressure include:

• Sepsis
• Hemorrhage
• Toxins including toxic doses of blood pressure medicine
• Hormonal abnormalities, such as Addison's disease

Shock is a complex condition which leads to critically decreased blood perfusion. The usual mechanisms are loss of blood volume, pooling of blood within the veins reducing adequate return to the heart and/or low effective heart pumping. Low blood pressure, especially low pulse pressure, is a sign of shock and contributes to/reflects decreased perfusion.

If there is a significant difference in the pressure from one arm to the other, that may indicate a narrowing (e.g., due to aortic coarctation, aortic dissection, thrombosis or embolism) of an artery.

Venous pressure

Venous pressure is the blood pressure in a vein or in the atria of the heart. It is muc h less than arterial blood pressure, with common values of 5 mmHg in the right atrium and 8 mmHg in the left atrium. Measurement of pressures in the venous system and the pulmonary vessels plays an important role in intensive care medicine but requires invasive techniques.

How can I prevent hypertension? Besides taking drugs, if that becomes necessary, how can I control it if I have it?

It's not certain that you can prevent it, but it's reasonable to think that the same practices that help control it might also prevent or postpone it. Here's what to do:

• Maintain a healthy weight. Losing even a few pounds if you're overweight can reduce blood pressure. Weight loss (achieved through diet and exercise) can sometimes bring hypertension under control without the need for drugs, or with lower doses of drugs.

• Don't smoke. A person with high blood pressure who smokes is at serious risk. Every cigarette raises blood pressure. Quitting lowers it.

• Exercise regularly. Exercise is useful in both preventing and treating hypertension. For one thing, it can help you lose weight. It can also lower your blood pressure somewhat, though it's not understood exactly how this happens. There are other benefits beyond blood pressure reduction: for instance, regular aerobic exercise reduces your risk of heart attack. If you are sedentary and just beginning an exercise program to combat hypertension, remember that you may not see the effects for months. But just 30 minutes of brisk walking four or five times a week can eventually make a difference.

If you already have high blood pressure and plan to exercise intensely, you should first discuss your program with your doctor. Neither exercise nor any other life-style modification is a panacea, however, or a substitute for antihypertensive drugs if these are needed.

• Eat a diet rich in fruits, grains, vegetables, and low-fat dairy products. For details the "DASH" diet.

• Keep your sodium intake low (below 2,400 milligrams daily). There's bitter dispute among scientists and others about this recommendation, but we think it's a good one. There's plenty of evidence that a high sodium intake drives up blood pressure in some people. A high-sodium diet has no advantages and many disadvantages. For instance, the typical salty diet is likely to contain lots of processed foods, be low in vitamins and minerals, and be high in fat. Reducing sodium intake is often an important step in treating high blood pressure.

• If you drink alcohol, do so in moderation: no more than one drink daily for a woman, or two for a man. (A drink is defined as 1.5 ounces of 80-proof spirits, 5 ounces of wine, or 12 ounces of beer, all of which contain the same amount of alcohol.)

What about vitamin supplements?

Researchers at the National Institutes of Health are currently studying the overall effects of diet on hypertension. It's difficult to isolate one nutrient from another and assess the effects that each may have on hypertension. You can't go wrong by increasing your intake of fruits, grains, and vegetables—these may have beneficial effects on blood pressure. Recent studies have shown that as produce intake rises, stroke risk drops.

We recommend vitamin C and vitamin E supplements for their antioxidant potential. It's not clear that they help prevent high blood pressure.

What about calcium, potassium, magnesium supplements?

These three minerals are important in blood pressure regulation. But there's no evidence that high doses of them from supplements will lower blood pressure and help prevent hypertension. Calcium supplements are a good idea for postmenopausal women, but we strongly suggest that you get some calcium and all your potassium and magnesium from foods, which also contain other nutrients you need. Nonfat or low-fat dairy products are the best sources of calcium, though some leafy greens are good, too. You need at least 800 to 1,000 milligrams of calcium daily; women over 50 and men over 65 should get 1,500 milligrams daily. Potassium is plentiful in most foods. Magnesium is plentiful in whole grains, leafy greens, meats, milk, beans, bananas, and nuts.

We've recommended a multivitamin/mineral supplement for many older people. If you're on hypertensive medication, your doctor may recommend potassium supplements.

Will taking fish-oil capsules decrease blood pressure?

High doses of fish oil (which contains omega-3 fatty acids) may lower blood pressure on a short-term basis in some people, but are not recommended for preventing or treating high blood pressure. High doses have potential adverse effects, including an increased risk for one type of stroke. Moderate doses have no effect on blood pressure.

Can coffee cause high blood pressure?

Any caffeine-containing beverage (tea, cola, or coffee) can temporarily raise blood pressure, especially if you are not used to caffeine. But caffeine is not known to cause hypertension.

Following are some botanical products and their ingredients, which produce excellent results:

Hyperexol:

 

Magnesium Oxide . . . Is vital for healthy heart cells. Evidence reveals that magnesium is an important element in regulating blood pressure and proper heart rhythm. A magnesium deficiency may contribute to abnormal heart rhythms, heart attacks, and strokes. If you suffer from high blood pressure, your doctor may have prescribed a diuretic (water pill) as a treatment. Diuretics work to lower blood pressure by purging excess water. However, vital minerals, including magnesium, are also purged out during in the process. The fact is, 90% of Americans do not get enough magnesium in their diets.

Calcium Carbonate and Citrates . . . are essential minerals with a wide range of biological purposes. As well as being important for bones and teeth, calcium is vital for muscle contraction, nerve conduction, beating heart cells, blood coagulation, glandular secretion, energy metabolism and the support of immune function, to only name a few! Calcium has antihypertensive and hypocholesterolemic activity. Calcium has been found to help in the lowering of systolic blood pressure, in patients with hypertension.

Potassium . . . is absolutely essential for proper functioning of the heart muscle, insulin release, proper fluid balance and nerve function. Researchers have found that it works wonders in reducing and regulating blood pressure. These days, potassium deficiency is very common because of high salt intake, which purges potassium from the body's storehouses.

Allum Sativa . . . amazingly, the benefits of garlic could fill a book. The Europeans use this herb as an all-around treatment for preventing atherosclerosis, heart disease and strokes. Scientific studies show that garlic helps to lower blood pressure and serum cholesterol levels. One study on hypertensive patients found that when 47 non-hospitalized patients with mild hypertension were administered either 600 mg of a garlic powder preparation or placebo for 12 weeks, after 8 weeks blood pressure was significantly reduced from 171/102 mmHg to 155/91 mmHg (Auer et al., 1990).

The Hawthorn Berry, Crataegus monogyna . . . is one of the oldest known medicinal plants used in European medicine Hawthorn berry is famous for its benefits on the circulatory system. Hawthorn has a long history of confirmed safety, and clinical evidence to support its cardiovascular benefits. (The cardiovascular benefits are the result of positive inotropic activity, it seems to have the ability to increase the integrity of the blood vessel wall and improve coronary blood flow, and positive effects on oxygen utilization.) Simply put, hawthorn berries are known for their ability to enhance metabolism and increase oxygen in the heart, which allows for protection of the arterial walls and dilation of the hearts' blood vessels improving the pumping of the heart cells. This helps reduce blood pressure as expanded blood vessels allow the blood to move more freely throughout the body.

Taurine . . . is a building block for all the other amino acids. Taurine bares an important role in protecting the potassium in the heart muscles, promoting healthier heart cells. L-taurine also supports the neurotransmitters and has a protective effect on the whole brain. Taurine is beneficial for patients with artherosclerosis, edema, heart disorders, hypertension, or hypoglycemia. It is amazingly successful in soothing anxiety and calming hyperactivity.

Vitamin C . . . Researchers from Boston University and the Linus Pauling Institute at Oregon State University found that after a month of taking 500 mg of vitamin C a day, patients with hypertension reduced their mean blood pressures an average of 9%, just with good old vitamin C alone!

Cayenne Pepper (Capsicum frutescens) . . . Cayenne has always been used for benefit of the circulatory system. Cayenne is a perfect food for the circulatory system because it helps supply essential factors for the cell membranes of the arteries, veins and capillaries and restores elasticity and vigor. By virtue of increasing the blood circulation, cayenne produces natural warmth that stimulates the peristaltic (digestive) motion of the gut, which helps in absorption of nutrients and elimination of toxins. Cayenne normalizes the healthy flow of blood from the head to the feet, regulating and equalizing all blood pressure.   BP Balance- Chinese blend: Ingredients: F. Sophora Japonica F. Notoginseng Hoo L.F. Prunella Vulgatise Suiong Husa Lonicera J Aponica Thumb Wet Huse Blood Pressure Support- European blend: Ingredients: Each 3 tablets contain a proprietary blend of standardized vita-nutrients of: Magnesium - 600mg Hawthorn Extract - 600mg Coleus Forskohlii Extract - 200mg Taurine - 300mg Hops Strobiles - 60mg Hyperten: Ingredients: CAYENNE - helps stimulate the circulatory system, influencing the heart immediately, tonic, regulates the flow of the blood from head to foot so that circulation is equalized GARLIC - help reduce the fat levels in the veins and arteries, dissolves cholesterol, boosts the immune system, reduces blood pressure, kills yeast infection, cleans plaque out of the arteries BLACK COHOSH - helps to loosen and expel mucus from bronchial tubes, equalizes blood circulation, nervine, alterative, excellent remedy for high blood pressure, calms the nervous system, do not take if pregnant MISTLETOE - tonic, tones the heart, nervine, helpful with heart problems, helpful with low blood pressure, dilates arterioles and capillaries, helps with an over-excited heart SASSAFRAS - alterative, blood purifier, cleanses the whole body, helps with spasms and pains in the heart region, stimulant, acts as a solvent liquefying impurities in the blood stream GINGKO - helps to improve the flow of blood to the heart, can help prevent strokes, inflammatory VALERIAN - has a beneficial effect on the heart and high blood pressure through its relaxing process BLADDER WRACK - helps to lower cholesterol, stimulates bile production, helps with digestion, supplies oxygen and iodine to the body, gives warmth and energy, contains trace minerals DONG QUAI - helps with palpitation and high blood pressure, strengthens and aids general circulation, helps to relieve tinnitus GINSENG - helps support the reduction of cholesterol and prevents heart attacks, has a beneficial effect on the circulation HORSETAIL GRASS - high in calcium, calcium has been shown to clean plaque out of the arteries HYSSOP - helps support the stimulation properties to increase blood circulation and equalizes the blood pressure BLADDER POD - a sedative herb, has a beneficial effect on the whole body, helps to loosen hardened mucus, expectorant, will reduce heart palpitations STINGING NETTLE - stimulant, tonic, stimulates nutrition, improves heart action, cleans the body of poisons WILD YAM - helps soothe the nerves and relieves pain, anti-inflammatory, anti-bilious, anti-catarrhal BAYBERRY - helps fight broncho-pulmonary diseases, used to increase circulation, blood builder, antibacterial There are many pressure points on the body because of a vaso vagal reflex (some are dangerous), will help lower blood pressure such as massaging the ear lobes for several minutes.  Meditation and breathing rythyms can help lower blood pressure.   As seen above, there are many causes of high blood pressure. Different regimes work for different causes. Consult the appropriate healthcare professional to help find one that works for you. UPDATES Newsletter Index Page [Home] [Newsletter] [Products] [Contact Us] DISCLAIMER:  The information in this column, is NOT intended to diagnose and/or treat any health related issues and is provided solely for informational purposes only. Consult the appropriate healthcare professional before making any changes to your healthcare regime. Even what may seem like simple changes in the diet for example, can interact with, and alter, the efficiency of medications and/or the body's response to the medications. Many herbs and supplements exert powerful medicinal effects. Neither the author, nor the website designers, assume any responsibility for the reader's use or misuse of this information. © 2002 Nature's Corner