Astrocytes in Molecular Layer of Cerebellum after Spatial Learning

　Introduction: Previous studies have suggested that the cerebellum is a primary site of motor learning. The cerebellar cortex has a particular glial architecture with large astroglial cells. In addition, more recent works have revealed that astrocytes play a more active role in neuronal activity. The aim of this study was to evaluate the number of astrocytes in the molecular layer of rat's cerebellum after spatial learning. 21 male albino wistar rats were used in this study. Reference and working memory methods of Morris Water Maze (MWM) were used. Following behavioral testing, animals were decapitated under diethyl ether anesthesia. Brains were removed and fixed for 2 weeks for histological assessment. Finally, 7 μm thick coronal slices were cut and stained with PTAH staining for showing the astrocytes. Results: Our results showed a significant difference in the number of astrocytes between the control, reference and working memory groups. On the other hand, the number of astrocytes in the working memory group was more than the other groups. There was no difference in density of astrocytes between the lateral and medial parts of the cerebellum in any group. It seems that the distribution of astrocytes in the lateral and medial parts of cerebellum is similar. Discussion: We concluded that spatial learning such as reference or working memory methods, can increase the number of astrocytes in the cerebellum and this increase is similar in the cerebellar cortex. Methods: