[Effect of sidnocarb during 7-day water immersion on the cardiorespiratory system under physical load]

To study physiological effects of weightlessness, 12 male volunteers, aged 25-33, were exposed to 7-day water immersion. The test subjects were divided into two groups of 6 in each: the first group subjects were given a new Soviet stimulant sydnocarb (3-(beta-phenylisopropyl) -N-phenyl carbamoyl sydnonimine) and the second group subjects were given a placebo, using the double-blind method. To evaluate the cardiorespiratory function, the test subjects exercised on a bicycle ergometer before and after water immersion. During exercises ECG, heart rate, minute respiration volume, oxygen consumption, carbon dioxide production, cardiac output, oxygen pulse were recorded. The test subjects on the placebo showed a significant decrease of oxygen consumption at at maximum workload. Those who were given sydnocarb maintained normal oxygen consumption during bicycle ergometry. The drug increased the workload per kg body weight, maintained physical work capacity, and improved the cardiovascular function after immersion.