Qualitative And Quantitative Studies On The Postnatal Changes Of Rat Brain Astrocytes

Objective To investigate the postnatal changes of brain astrocytes in morphology.Methods Experimental rats were randomly divided into five groups with five rats in each groups: postnatal one day (P1) , postnatal one week (P7) , postnatal two weeks(P14), postnatal three weeks(P21 )and postnatal four weeks (P28) . Immunohistochemical method was used to observe the changes of glial fibrillary acidic protein (GFAP) expressed by astrocytes in hippocampus (CA1), caudate putamen nuclei, black substance and cerebral cortex of the above five rat groups.Results The shapes of astrocytes (GFAP-immunopositive cells) in the four brain divisions were similar, while the sizes of the cells gradually became large as the postnatal days extended. In addition, the number of the astrocytes in the four brain areas was also significantly increased with postnatal days (P< 0.05) .Conclusion The above postnatal change patterns of both morphology and number of the astrocytes may serves a valuable parameter for judging the postnatally developmental extents of the brain.