ARTIFICIAL HEART

Dominion, Volume 29, Issue 274, 15 August 1936, Page 4

ARTIFICIAL HEART

Biological Importance Of Invention FIGHTING DISEASE Chicken Cells Which Are Immortal The invention of an artificial heart, for ■ which Colonel C. A. Lindbergh is being recommended for the Noble science prize, was first reported from New York in a message of June 21, 1935. which stated-that Lindberg and Dr. Alexis Carrel, working under the auspices of the Rockefeller Institute for Medical Research, had perfected apparatus and technique capable of keeping human organs alive outside the body. In a joint) statement, Colonel Lindbergh and Dr. Carrel said at the time that they had created au artificial heart and a man-made blood stream, enabling science for the first time to keep vital organs alive and functioning indefinitely in what was described as a chamber of eternal life. They pointed out that this was not a substitute for the well-known tissue culture. Tissue culture dealt with cells as units. The structure of their method dealt with cellular societies as an organic whole. The method made possible the carrying out of iinportant..experimentation with human organs. Heart disease, kidney disorders, hardening of the arteries, diabetes, tuberculosis, cancer and other dread diseases could now lie studied closely under controlled conditions. Astonishing Experiments. Work on tissue culture, leading up to the invention of Dr.'.Carrel and Colonel Lindbergh was outlined to ‘'The Dominion” yesterday by a Wellington j biologist. In-1781, he said, the famous > Abbe Fontaha reported that it was • possible to cut off the heads of, rabbits and guinea pigs and keep their bodies alive by connecting a pair of bellows with the windpipe, thus maintaining artificial respiration. The headless bodies responded to stimulation and showed evident signs of life. ' < In 1830 Legallois published an account of experiments more advanced than Fontana’s. He removed a rabbit’s head,' tied the blood vessels, and then cut away the whole of the posterior part of the body, leaving only the headless thorax. Even this fragment,remained alive, and the forepaws showed sensibility when irritated. , Brown-Sequard,'iii the latter: part of last century, performed the most astonishing experiment of this kind. He cut off the head of a dog immediately it had , been killed and connected the carotid and vertebral arteries with an apparatus for artificial respiration. Af- . ter eight or 10 minutes had elapsed fresh blood was run into the head through the apparatus; and in a few seconds signs of life, such as movement of the eyes, appeared. About this time Ludwig and his pupils succeeded in maintaining an artificial circulation in many excised organs, including the mammalian liver, the mammalian lung and the frog’s heart. Many Types of Cell Grown. More recently an ever-increasing volume of research, taking its origin from the pioneer experiments of Harrison, had been concerned with tissue culture .or- the growth of tiny pieces of tissue in small sealed and sterile chambers on microscopic slides. Cells grown in a suitable medium at a temperature of a half-degree above that of the body would divide and grow and show all the activities of life. Nearly all types of cells from the mammalian body had been grown in this way—muscle, nerve, connected tissue, cancer, blood and other cells. s This method had been limited, however, because of the necessity for transplanting part of the culture to a fresh medium in a new chamber every few days to avoid injurious effects of oxygen lack and the accumulation of waste products. Using the transplantation technique, experimenters had been successful in spite of this difficulty in keeping chicken heart muscle aliv e for 12 years and longer. One of the most enterprising workers in this field had been Dr. Carrel. By the use of special flasks and media he obviated the necessity of transplanting the cultures and was able to grow large sheets of tissue for considerable periods. This history of tissue culture and its improvement was mainly the story of the discover}' of increasingly efficient mediums to act as blood substitutes. It would appear that the chief advance made by Dr. Carrel and Colonel Lindbergh was in the use of the nutrient fluids perfected in the last few years of tissue culture. In this way the limited time during which an organ could be kept alive would seem to have been indefinitely extended. Immortal Chicken Heart. In his latest book, “Man, the Unknown.” Dr. Carrel says:— The technique used in the preparation of a- culture accounts for the rhythm of life of such culture. For example, a fragment of heart, fed with a single drop of plasma in the confined atmosphere of a hollow- slide, and another one immersed in a flask containing a large volume of nutritive fluids and gases, have quite different fates. The rate of accumulation of the waste products in the medium, and the nature of these products, determine the characteristics of the duration of the tissues. When the composition of the medium is maintained constant, the cell colonies remain indefinitely in the same state of activity. They record time by quantitative, and not by qualitative, changes. If, by an appropriate technique, their volume is prevented from increasing, they never grow old. Colonies obtained from a heart fragment removed in January, 1912, from a chick embryo, are growing as actively to-day as 23 years ago. In fact, they are immortal.