Science has recently revealed new insights into the human body. A vast information network like the internet exists inside. Formerly, scientists thought the brain ruled all body systems and that the other organs merely obeyed its commands.

Now this idea has been completely overturned. Our internal organs communicate directly with one another through the exchange of chemical messages, often completely bypassing the brain. These messages might hold valuable keys to our health and longevity as new discoveries suggest that most illnesses are signs of disruption in the dialogue between organs.

Intervening in these chemical dialogues might show modern medicine paths to overcome many diseases that previously were thought to be untreatable.

One of the most important organs are the kidneys. They are much more than dull organs that only produce urine. They are drawing attention the world over, with more multiple roles than any other organ. By sending chemical signals throughout the body, they hold a high command position among the body’s networks.

For example, when blood oxygen is low, the kidneys release a molecule, called EPA, that tells other organs, “We need more oxygen.’’ Carried by the bloodstream throughout the body, various organs react accordingly. For example, EPA signals the bones to increase red cell division. The more red cells, the better the blood’s ability to carry oxygen, thereby improving physical endurance.

The kidneys produce many more chemicals that play a crucial role in maintaining our health.

Renin triggers contraction of blood vessels, thereby raising blood pressure. Kidneys are constantly fine-tuning renin to control blood pressure. In many hypertensive patients the kidneys are producing too much renin.

Kidneys are managers of blood. The total length of blood vessels in the human body is around 62,500 miles, 2-1/2 times around the globe. Blood carries oxygen and removes waste product but also serves as an information channel for information molecules produced by various organs.

Not surprisingly, blood vessels are highly concentrated in the vicinity of the kidneys.

A technique called nanomicroscopy, which won a Nobel Prize for its three inventors in 2014, allows unprecedented views into cellular processes that before had been only a blur. It is thousands of times more powerful than the highest magnification by ordinary light microscopes, which are limited by the wavelength of light used in the scope.

Inside the kidneys are tiny structures called glomeruli merely 0.2 millimeters across. Blood enters glomeruli and “leaks” out through tiny perforations. Holes in the glomeruli are too small for red blood cells but large enough for molecules of essential chemicals and waste to pass through.

The glomeruli contain long, cavelike tubes (renal tubule) that have a lining of thin, rodlike cells called microvilli. The microvilli have ion exchange pumps scattered across their surface. Each pump absorbs only a specific kind of molecule. For example, salt pumps increase absorption to return the salt molecules to the bloodstream when the body needs salt.

The amount of each chemical is fine-tuned by a pump unique to that type of molecule. The pump either absorbs the molecule and returns it to the bloodstream or lets it pass into the urine with other waste products. The kidneys respond to messages from other organ systems to “decide” which of each chemical and how much should be reabsorbed into the blood.

As the internal messaging network is more extensively studied, we will learn more about its role in health and disease, and hopefully it will provide pathways to fight conditions as diverse as cancer, diabetes and rheumatoid arthritis.

Richard Brill is a retired professor of science at Honolulu Community College. His column runs on the first and third Fridays of the month. Email questions and comments to brill@hawaii.edu.