Presentation Speech by Professor Bengt Pernow of the Karolinska Institute

Translation from the Swedish text

Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,

Hippocrates, the Father of Medicine, taught us that good health requires the four humors – blood from the heart, phlegm from the brain, and the yellow and black bile from the liver and spleen – to be in harmony with one another, or to put it simply, that we have sound humors. The teachings of Hippocrates also speak of the body’s efforts to stay healthy and its constant battle against disease.

This more than 2.000-year-old concept may be said to prevail even today. Within the complex system that makes up the human body, it is essential that there be a balance between not only the organs but the individual cells. Their ability to interact determines our actions and our attitudes at any given time. A disturbance of this balance leads to undermined health. To maintain the balance and to prevent it from being upset by external or internal stress factors, nature has provided us with a number of regulatory systems. Prostaglandins and related biologically active substances constitute one of these systems.

It was Professor Ulf von Euler who opened up this area when he showed, almost 50 years ago, that seminal fluid in man and animals contains a substance that influences blood vessels and muscle fibers. He called the newly discovered substance Prostaglandin. Von Euler was awarded the Nobel Prize in 1970 for his fundamental discoveries within the fascinating world of hormones and signal substances.

The great breakthrough in prostaglandin research came in the late 1950s when Sune Bergström purified the first prostaglandins and determined their structure. This marked the beginning of the discovery of a hitherto entirely unknown biological system that regulates several vital life processes and that intervenes when the body’s normal balance is disturbed. The widespread involvement of this system is indicated by the fact that almost all cells in our body have the ability to form one or several of its components. John Vane has called them defense hormones. Time permits me to give only two examples of how the system works.

Blood is constantly flowing in our blood vessels. But the blood cells have a tendency to bunch up to form blood clots that stop blood flow. To prevent this from happening in healthy and intact vessels, substances that belong to the prostaglandin system are constantly being formed within the vessel wall and the blood cells. These substances see to it that the blood can circulate without interruption. If this system is upset, formation of blood clots is inevitable. Our white blood cells form a defense barrier against infection. Therefore, it is important that these blood cells converge on an inflamed tissue to attack and, if possible, destroy the injurious intruders. The latest addition to this biological system – the leukotrienes, recently discovered by Bengt Samuelsson – play an important role because of their ability to lure white blood cells to the site of injury and bind them to the vessel wall.

Thus, this entire array of substances indeed warrants the name defense hormones.

However, here as elsewhere, moderation is essential. In certain situations, such as in allergic reactions, prostaglandins and leukotrienes are overproduced and give rise to the entire set of symptoms that characterize allergies. When, for example, an asthma sufferer is exposed to the specific substances to which he or she is over-sensitive, leukotrienes are produced in large quantities in the lungs and trigger the severe asthma attack.

Thus, the knowledge acquired of how this system is formed and how it functions has to a significant degree increased our understanding of how our bodies can keep our humors sound. But it has also taught us to understand the mechanisms behind a number of widespread diseases – allergies, inflammations and vascular diseases, to name a few. This new knowledge has, in turn, provided the prerequisites for enabling us to more specifically, and thus more effectively, threaten these disorders and prevent their occurrence.

It is no wonder that prostaglandin research is now being carried on all over the world. Nevertheless, the researchers who once were the pioneers and still continue to lead development in the field are Bergström, Samuelsson and Vane.

As mentioned, Sune Bergström laid the groundwork for the current development by isolating the first prostaglandins and showing that it was not a matter of one substance but of a whole system. Bergstrom showed, too, that unsaturated fatty acids form the parent substance for this system, and thereby focused research attention on these acids.

Bergstrom’s student, Bengt Samuelsson, is responsible for the chemical development since the 1960s. He has isolated and determined the structure of several of the most significant components within the system. More thoroughly than anyone else, he has explained for us how this complicated system is built up, and has helped us to understand the relationship between its various components. Among John Vane’s contributions may be mentioned the discovery of an important component of the system – prostacyclin. Vane has also revealed that the secret of the pain-relieving and fever-reducing properties of acetylsalicylic acid is its inhibition of the formation of prostaglandins. We are more familiar with acetylsalicylic acid under the name aspirin. All at once Vane was able to explain how this most widely used medicine in the world, for whose existence we have all had reason to be grateful at one time or another, actually functions in our bodies. By this discovery, Vane also provided an important weapon for those continuing the research directed towards establishing the functional role of the prostaglandin system.

The scientific contributions we are rewarding today have inspired researchers all over the world, and prostaglandin research may now be said to have entered its most dynamic phase. At the same time it may be said to be a beautiful example of how support to basic research has turned out to be a very good investment for society as a whole.

Drs. Bergström, Samuelsson and Vane,

Your discoveries have revealed for us a previously unknown biological system that not only plays a decisive role in normal life processes but also contributes to the imbalance that characterizes several diseases. Proceeding from varying points of departure you have, together, clarified the structure, biological properties and fundamental functions of this system. Your discoveries have stimulated an entire world in their intensive research aimed at finding the causes and cures for a number of diseases of importance to mankind.

On behalf of the Karolinska Institute and its Nobel Assembly I have the privilege to convey to you our warmest congratulations, and I now ask you to receive your Nobel Prize from the hands of His Majesty the King.