Effects of diet composition and length of feeding restriction on the locomotor rhythms of Mus musculus
Files
TR Number
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Changes in locomotor rhythms of Mus musculus as a response to combinations of lighting and feeding cues were quantitatively assessed in this study. Time allowed for feeding was varied (3, 5, and 7 hours) to examine effect of different zeitgeber strengths on locomotor pattens. The effect of temporal light/dark cue removal on locomotor rhythms was examined in conjunction with restricted feeding regimes. The potential to use blood glucose levels as a temporal feeding cue was examined by comparing the locomotor rhythms of mice consuming either a high glucose or high starch diet. Blood glucose curves for animals under restricted feeding regimes of 1 and 5 hour lengths were determined for the two diets.
Most of the locomotor activity records from animals in total darkness and a restricted feeding regime contained rhythm splitting. Only the anticipatory component of locomotor activity was synchronized by the 7 hour and 5 hour restricted feeding regimes in total darkness. Mice on a 3 hour restriction regime also exhibited a free run component in locomotor activity. The two experimental diets did not produce statistical differences in plasma glucose concentrations when animals were placed on a 5 hour restricted feeding regime in total darkness, but did when they were placed in a light/dark l2:l2 lighting cycle with a 1 hour feeding regime. The locomotor records indicated that free-running locomotor components were synchronized only by light/dark transitions, while the anticipatory component was synchronized by food presentation. The results of this study are consistent with a Two-Oscillator Model for control of activity rhythms.