Description: Segment 1 The narrator introduces the concept of stress in medical terms, and how this film tries to explain stress as conceived by Dr Hands Selye in 1936. His experiments are re-enacted in the film. The first experiment shown is the injection of ovarian extract into rats, which is the first experiment that drew Dr Selye's attention to 'non specific biological stress' in 1936. The injections resulted in unexpected changes in some body organs, which are shown in the film the stomach is covered in ulcers, the thymus is smaller than normal and the adrenal gland is larger than normal. The narrator discusses the results of this experiment over images of the rat's organs. Next, different types of organ and muscular extract are injected to see if the same changes occur. They do, and a simple damaging substance is injected as well. This also results in the same organ changes. Time start: 00:00:00:00 Time end: 00:06:55:03 Length: 00:06:55:03 Segment 2 A lecturer in front of a group of students asks what cases these changes in the body (this is presumably an actor playing Hans Selye). The narrator explains that in the following months and years, various forms of trauma were investigated, and a montage of different experiments is seen. These include subjecting rats to x-rays, toxic substances, over-exercise, exposure to intense light, mental stress and immobilisation. Each experiment resulted in the same organ changes as before. A diagram shows the two types of reaction to an injury the first is the specific effect of the injury, and the second is the non-specific effect, common to all injuries. Further experiments are re-enacted a rat's back is burnt and bacteria is injected in another rat. The rats are dissected to show the organ changes. The non-specific reaction to injury is stress, and a diagram also names it as 'general adaptation syndrome'. A chart lists the three stages of the syndrome, the first being the alarm reaction. Time start: 00:06:55:03 Time end: 00:12:34:12 Length: 00:05:39:09 Segment 3 The second stage of the syndrome is the stage of resistance, and the third is the stage of exhaustion. Footage of an experiment follows, where a rat is made very cold. The cold is intensified and another rat added to the experiment. The first rat adapts to the intense cold because of its previous exposure. Finally, the rats reach the stage of exhaustion, which terminates in death. The narrator explains that it is not completely understood how the organ changes occur, but that it is understood that the pituitary gland plays a part. Another experiment is shown, which injects rats with an inflammatory agent. One rat is treated with hydrocortisone and is not affected. The difference in response is demonstrated. Time start: 00:12:34:12 Time end: 00:18:57:03 Length: 00:06:22:16 Segment 4 An illustration explains the findings of the previous experiment. The effects of inflammatory hormones are shown in a series of experiments. In these experiments, air pockets are created in the backs of rats, and then various inflammatory or anti-inflammatory agents injected into the air sacs. The results of the different injections are compared by cutting the air sacs out of the rats' backs and examining them. Time start: 00:18:57:03 Time end: 00:25:56:01 Length: 00:06:58:23