[Serotonin-producing cells during normo- and hypothermia].

Ultrastructure of the serotonin-producing (EC) duodenum cells of a hibernant in euthermia (in summer and winter) and hypothermia has been studied. It has been found that EC cells of an active summer and spontaneously arousal animals belong to active population. This cells have protein-synthetic activity. The winter cells are characterized by the deficiency of the synthetic processes and the secretory granules disintegration. The results support the hypothesis that ES cells are an important element in the regulation of the hibernation.