The Influence of Constant Lighting on The Daily Dynamics of Some Physiological Parameters of Male Wistar Rats
The effect of the stay of 6-months-old male Wistar rats under the influence of constant lighting on the daily dynamics of some biochemical parameters was studied. Male Wistar albino rats at the age of 6 months were divided into 2 groups. The rats from the Group I were housed under a fixed illumination, L:D 14:10 (±180 lux, respectively; 8:00 AM lights on) (unless mentioned otherwise) in a temperature-controlled environment with ad libitum access to tap water and food (rat chow). Animals of Group II were studied under the same experimental conditions except for the light regime, representing constant light (LL ±180 lux). Both the first and second groups of animals were kept at the specified light regime for 2 weeks. A number of biochemical parameters of blood plasma have a reliable daily rhythm, while for other metabolites of an organism a circadian rhythm is not noted. The appearance of the previously absent rhythm of physiological parameters after the application of constant lighting indicates the role of other pacemakers in the metabolism, in addition to illumination. The conducted research testifies about the unambiguous modulating influence of constant illumination on the structure of diurnal dynamics of studied biochemical parameters and rectal temperature, and about the initiation of desynchronosis by it.