Light and Kidney Function

Abstract

Observations concerning the temporal aspects of water excretion go back to the last century. The first exhaustive studies, which are still relevant today, were made by Quincke (1877, 1893). Quincke was the first to observe the matutinal flow of urine. From this observation as well as from experiments demonstrating that the nocturnal decrease in urine occurs only when sleeping in a horizontal position, Quincke concludes that this position promotes excretion of urine. Jores (1935) conducted tests pertaining to this question on ten night watchmen. He divided fluid intake equally over a period of 24 hours, with food intake occurring only during the night. The relationship between diurnal and nocturnal urine patterns did not change. A further shift toward diurnal excretion even became evident. A recumbent position during the day promoted water excretion, as already discovered by Quincke and, after him, a whole series of investigators (Seyderhelm and Goldberg 1927). Jores concludes from this that sleep as such cannot directly inhibit water excretion, especially since among his experimental subjects there was one person who had been continuously employed for eight years as a night watchman so that the deficiency of excretion during the experiment could not be the result of adaptation to the reversal in life pattern.