TIME OF DAY, ENVIRONMENT LUMINOSITY AND PHYSICAL EXERCISE EFFECTS ON INFLAMMATORY AND PERFORMANCE PARAMETERS OF SWIMMING RATS

ABSTRACT

Animal models are quite used for inferences to Human beings regarding many physiological mechanisms, however, current experiments have been neglected adequate control on environment and chronobiological interferences. The aim of this study was to analyze inflammatory responses owing physical exercise kept until exhaustion at aerobic/anaerobic transition intensity in different times of day and environmental luminosities. Wistar Rats were submitted to a two environmental luminosities during night period: standard luminosity (SL; total darkness) or experimental luminosity (EL; >600nm; <15lux). Animals were submitted to the lactate minimum test and then submitted to an exhaustive exercise at such intensity (TE). Overall experimental procedures were performed at 12:00h or 20:00h. TE were not influenced by time of day or environmental luminosity, nevertheless, were found reduced scores to inflammatory markers to rats assessed under SL at 20:00hs, showing the importance of such control in experiments involving nocturnal animals.

Keywords
Chronobiology; Performance; Rats; Inflammatory parameters; Luminosity