Some effects of acceleration in man and chimpanzees

Early physiologic experiments using dogs and humans in centrifuges are reviewed. Because of the close similarity between the shape and dimensions of the thoraces of chimpanzees and humans, the former were used to obtain roentgenograms and photokymographic recordings of multiple physiologic variables before and during exposure to +5.8 Gy to study the effects of changes in the gravitational-inertial force environment on the cardiovascular and pulmonary systems during long duration space flight. A computer-controlled sciscanning system was used to obtain a two dimensional map of the amount of radiation emanating from the dorsal and ventricle surfaces after insertion of radioactive microspheres in the right ventricle. By using four different batches of microspheres tagged with isotopes of different energies, the spatial distribution of pulmonary blood flow under four conditions was determined.