[Circadian rhythm in the functional activity of mast cells of the dura mater of rat brain].

The Falk-Hillarp method was used to study circadian activity of the rat dura mater mast cells and the content of monoamines in them. The quantitative changes in the mast cells are described as time-dependent. The data obtained were statistically analyzed to disclose the latent periodicity of the processes occurring in the mast cells. A twenty-four-hour cycle of the cell activity was discovered. Two functional states of the mast cells were distinguished: (a) the maximum of degranulating mast cells was recorded at noon; (b) the maximum of intact fat cells was seen at 3 p. m.