Dr. Arthur C. Guyton

A legacy of achievement

A form of natural selection takes place in the stories people remember about a person - a process that makes the selection more important than the facts.

Some of the stories about Arthur Guyton may sound apocryphal, but they illustrate the man and his legacy to his students, this institution and the world of science.

Dr. Elvin Smith, a former student who is now associate dean for research at Texas A&M University, likes to tell the story about moving day in 1955 when the young Dr. Guyton oversaw the move of the physiology department from the medical school in Oxford to the brand new Medical Center in Jackson.

He had been chairman of physiology since 1948 and had inherited a machine shop from the late Dr. Charles Potter, a former chairman at the Ole Miss school.

It had to come to Jackson. Both the financial climate of the times and Dr. Guyton's widely recognized frugality prohibited the building or buying of additional equipment when the old was entirely serviceable.

Once in Jackson, the lathe, drill press and sheet metal break had to be transported by elevator to its sixth floor home in the new building. But the moving contractor estimated the weight of the equipment and decided it far exceeded the elevator's capacity.

He would not take the responsibility for moving it.

Dr. Guyton asked his technician, Ginger Howard, to climb the elevator and measure the size of the cable supporting it. From his perch, he called down the numbers. Dr. Guyton paused for a few moments while he did the mental calculations and said, "take the equipment on up. I'll be personally responsible for it."

The equipment is still there, still in service.

It was a fitting beginning for Dr. Guyton's career at the Medical Center. It shows what he taught his students about not accepting things at face value and about taking intellectual risks and the responsibility for the results.

By 1955, Dr. Guyton had used wheelchair and crutches since 1947 because of the residual paralysis of polio which he contracted as a surgical resident at Massachusetts General Hospital in October 1946.

During those eight years, he and his wife Ruth had made many pivotal decisions about their future.

They both knew they still wanted a large family. Cardiovascular surgery was no longer an option because of the paralysis. But medical research, particularly in hypertension, was an attractive career choice.

Despite several offers to this promising young scientist to stay in the Boston area, the Guytons had decided to come home to Oxford.

By 1955, they had six of the 10 children who would complete their clan. His famous book, going into its ninth printing, Textbook of Medical Physiology, was most likely in galley proof stage at the time since the first edition came out one year later. But he was also back to the basics in circulation. He had failed to find the cause of hypertension.

Rediscovering the circulation

In a way, he had to "invent" the circulation. While hunting for the elusive cause of hypertension, he discovered more and more unanswered questions about basic cardiovascular function. If he was ever to answer what to him was the ultimate question (what causes high blood pressure) he had to answer a host of other questions as well, had to solve the master puzzle one piece at a time.

That process really began in earnest at the Medical Center, and putting his name on the new laboratory research center, designated for the pursuit of scientific knowledge, is a fitting tribute to the international recognition he has brought this institution for his innumerable scientific accomplishments.

Year by year, Dr. Guyton filled an information void about heart and blood vessel function with several key puzzle pieces.

Overturning conventional wisdom

In the 1950s, he described the "permissive" heart to explain the amount of blood the heart pumped, or cardiac output. The heart would pump only what was delivered to it through the veins. When body tissues need extra blood flow to carry required oxygen and other nutrients, the blood vessels in those tissues expand or dilate, to allow increased flow. The control of cardiac output, he decided, was vested in the periphery.

He completely overturned the conventional wisdom that the heart itself controlled cardiac output. This, like his later findings, flew in the face of prevailing thought. But as he proved when he took responsibility for moving the machine shop, he never took things at face value.

A little later, he succeeded in measuring the pressure of the interstitium, the fluid between cells which makes up about one-sixth of the body. No one had been able to measure it before, and few scientists were ready to accept Dr. Guyton's finding of a negative, or subatmospheric, pressure.

Current department chairman Dr. John E. Hall, a world famous physiologist in his own right, is also a former student of Dr. Guyton's. He had read of Dr. Guyton's work on the interstitium while he was a graduate student at Michigan State University and reported on it to colleagues. A little later, he succeeded in measuring the pressure of the interstitium, the fluid between cells which makes up about one-sixth of the body. No one had been able to measure it before, and few scientists were ready to accept Dr. Guyton's finding of a negative, or subatmospheric, pressure.

"I was almost hooted down," Dr. Hall recalls. "My chairman wasn't impressed. But Guyton was right."

Many of the mechanisms of edema are now clearly understood in light of Dr. Guyton's discovery.

In 1966, an early computer model gave Dr. Guyton the answer to the question he'd been asking since he was a medical student. He wanted to show the effect of an increase in fluid volume and had predicted that the extra volume would cause an initial rise in pressure which would then fall back part way toward normal. That didn't happen. The pressure fell all the way back to normal. This led to the "infinite gain" theory which said that fluid volume control by the kidney can be so powerful as a long-term regulator of blood pressure that other systems can only regulate pressure short-term and will eventually be overpowered by the key controller.

Even Dr. Guyton, not given to hyperbole in speech, describes the theory of infinite gain as "really very revolutionary." Of course, it too, had to fight for acceptance among scientists who were still trying to apply the "mosaic" theory to high blood pressure.

A giant in a world of science

The list of Dr. Guyton's awards and honors is evidence that the world community of scientists eventually not only accepted his findings but recognized their vast importance.

He has published hundreds of papers sharing the results of his research. And he has written scores of books, including his most famous textbook, perhaps the best selling medical textbook of any kind and certainly the most widely used physiology text in the world.

And yet he always had time for students - for the medical students who had trouble understanding a portion of their lecture and for the graduate students who came from all over the world to study with the famous Dr. Guyton.

He and his students were colleagues, partners in the journey to understand. He wants them to get more credit for work generally attributed to him. They, in turn, feel no such desire. "If we, as former students, have achieved success in our fields," Dr. Hall has said, "it is because we have stood on the shoulders of a giant."