I. G. Vlasova, V. I. Torshin, Y. P. Starshinov

Oscillatory qualities of separate nervous cells (Purkinje cells) was investigated in vitro, i.e. on a neuronal model - survival slices of rats cerebellum. Daily and seasonal fluctuations in amount of active neurons, generating impulse activity (IA) of three types: continuous, bundle, bundle-explosive. For all seasons peak of neuronal activity was observed at evening and night period (18-24 hours), when neurons with bundle and bundle-explosive type of activity prevailed, what evi-denced high initial depolarization of nervous tissue at this period of twenty-four hours. Diminishing of active neurons amount occurred at day time (12-18 hours), which correlated with motion activity of animals having night life style (rats, mice). Spring (200 neurons) and au-tumn (118 neurons, generating IA) turned out to be the most active seasons. While in summer 88 spontaneously active neurons were registered, in winter - 75. In all seasons but winter acrophase of neuronal activity was observed from 9 to 12 a.m., when exogenic component of biorhythms re-vealed itself. It was associated with feeding of lab animals at this period of twenty-four hours, which turned out to be fixed genetically in these animals and mostly expressed at transitional seasons (spring, autumn). Thus nervous cells in complete isolation from integrating influence of the whole organism and its systems save their oscillatory qualities, reflecting daily and seasonal rhythmical activity of this species of animals. Given scheme of temporal organization of alive systems is discussed.