Vivisection

VIVISECTION (from Latin vivus - living and sectio - cutting), or live dissection, is a concept that includes not only operations performed for the purpose of studying various phenomena in just-operated animals (acute experiment), but also cases of preparing an animal by means of various surgical techniques for further (sometimes very lengthy) observations. The study of the animal organism, strictly speaking, began with the dissection of animal and human corpses. This method, valuable for clarifying the architecture of both the whole organism and its constituent parts, left open the question of the functions of the object being studied. If attempts were made to obtain an understanding of the role of a particular organ in an animal organism based on anatomical data, these attempts in most cases led to erroneous conclusions. A classic example can be the conclusion of Erasistratus, an anatomist and physician of the Alexandrian school, regarding the role of arterial vessels. Finding the arteries empty in corpses, he considered them air-carrying vessels through which air, not blood, moves. The famous Galen was one of the first to apply the vivisectional method and obtained many valuable physiological facts. In subsequent times, the vivisectional direction sometimes subsided, then again gained followers in the persons of the most prominent representatives of medicine of one era or another (e.g., Harvey, 17th century), but as a solid research method, V. was introduced into the laboratory in the early last century by Johannes Müller (1801-58) and Magendie (1783-1855). A series of subsequent researchers, in the persons of Claude Bernard, Ludwig, Goltz, Heidenhain, Pavlov, and others, proved that progress in biology and medicine is unthinkable without the broad and rational application of the vivisectional method, which opens the way to studying not only the normal functions of body organs, but also the causes of deviations of these functions under various physiological and pathological conditions. At present, research on operated animals forms one of the main contents of experimental medical sciences - physiology, pathology, and pharmacology. The tasks to be resolved with the help of V. are, in their main features, reduced to: 1) observation of organs in activity (work of the heart, movements of the intestines, etc.); 2) creation of appropriate conditions for studying the course of normal processes in the organism (fistulas of the digestive tract, etc.); 3) complete or partial removal of the organ being studied from the animal's body (brain, endocrine glands, etc.) or its exclusion from the general course of life processes by disrupting various connections (Eck's fistula, nerve section, ligature isolation of an organ, etc.); 4) enhancement of its functions by various irritations, transplantations (stimulation of chorda tympani, transplantation of sex glands, etc.); 5) study of changes in the normal course of life processes under artificially created conditions (artificial pericarditis, pneumothorax, etc.); 6) study of these changes upon the introduction of various chemical agents into the animal's organism (pharmacological research). Some of these tasks can be performed by means of acute experiment, others require the application of the method of preliminary preparation. The acute experiment, which has given and still gives so much to physiology, is very valuable for the analysis of phenomena, but is little suitable for synthetic constructions. The measures taken for the purpose of anesthetizing the operation and immobilizing the animal (anesthesia, spinal cord section), and finally the operation itself, disrupting the integrity of organs and tissues, cannot but affect the life processes in the animal's organism, obscuring some, enhancing others, and in general distorting the picture of the normal course of phenomena. In addition, the acute experiment excludes the possibility of longer, systematic observations. The shortcomings just listed can be eliminated by the method of preliminary preparation of the animal, which consists in the fact that after an operation performed on an animal for the purpose of making it suitable for various observations, the animal is kept until full recovery, and observations are made on a healthy animal. This method received particularly vivid expression in the brilliant works of I.P. Pavlov and his school. There is no doubt that physiology, pathology, and pharmacology, strengthened by vivisectional experiments, in their further development are inextricably linked with the application of vivisection.