Search

Incretins are hormones with a wide range of biological activity. We studied the ratio of the glycemic effect of the glucagon-like peptide-1 mimetic and its effect on the renal excretion of sodium and water. It was found that both effects depend on the initial blood concentration of glucose. In normoglycemia, exenatide had no effect on blood sugar level, but it significantly increased urinary sodium excretion and reabsorption of solute-free water. In hyperglycemia the blood glucose concentration was normalized by exenatide, while the excretion of sodium by the kidneys and the reabsorption of solute-free water were increased to a small extent. This pattern was found both in patients with type 2 diabetes mellitus and in rats with hyperglycemia induced by intraperitoneal injection of glucose.

During the long-term stay in closed environment of the orbital space station, it is extremely important that the light conditions and color scheme were favorable for the working capacity of a cosmonaut. The systems of lighting should ensure visual comfort for the crew members under stressful conditions and, in addition, they should appropriate to their health and recovery of functional reserves during the long-duration flight. To solve this task, the distribution of luminosity and chromaticity within a closed space should be taken into account. For better understanding the perception of visual information, we studied the color space-frequency characteristics of the organ of vision (SFC VO). A set of sensors was used to estimate psychophysiological parameters. After preadaptation of an operator, VO contrast sensitivity was measured by determining the thresholds of advent and disappearance of the test objects; this was accompanied by fixation of the time and adaptive brightness. Analysis of the experimental data made it clear that the color contrast sensitivity and directly related SFC of the organ of vision are valuable markers for interrelationships between processing of visual information and psychophysiological state of a human. Note that the color SFC VO not only illustrates deviations but also enables their quantification. Changes in psychophysiological state are accompanied by the appropriate changes in SFC VO, which should be taken into account in developing the neural information technologies used for health recovery and light-and-color control of environment.

The rate of excretion of the total protein and albumin during an increase in diuresis after water loading was studied in healthy volunteers. In the control period, the excretion of protein (7.3–11.1 mg/2 h) and albumin (0.29–0.42 mg/2 h) was within of the physiological norm range. Water loading (20 ml/kg) caused water diuresis, urine formation rate increased by a factor of 15, and the reabsorption of solute-free water changed into its excretion. The increase in diuresis was accompanied by a statistically significant increase in the urinary protein and albumin excretion, as well as by an increase in the protein-to-creatinine ratio. After water loading, the excretion of total protein, as compared to the initial period, increased by a factor of 8.4, and of the albumin excretion, by a factor of 2.8, exceeding the generally accepted limits of the norm. The role of intraglomerule hemodynamics in the development of physiological proteinuria related to water diuresis is discussed.