[Dynamics of the state of the granulation tissue after trauma inflicted at different times of day]

Dynamics on number of fibroblasts and amount of collagenous fibres in the granular tissue of the mouse ear skin was studied after trauma inflicted at 7 a. m., 15 or 23 p. m. The material was taken for 20 days by means of the method for dynamic observation. The cells and fibres were counted by means of the ocular grid (200 knots per 0.33 mm2). The course of the process was approximated according to the method of the least squares, the linear regression equations and according to the method of sliding averages. All stages of the inflammatory reaction after the night operation began with 20-24 hours' retardation if compared with the course of the process after the a. m. and afternoon operations. The fibroblast proliferation in the granular tissue was more active at once, their number increased more quickly. The collagenous fibre amount increased more quickly, too, but steadily during the course of the experiment. The peculiar features of the postoperative reactions to the operations performed at various times of the 24 hours' span were connected with the circadian phase of the organism's state at the time of the operation.