Abstract
The astrocyte plays a major role in the maintenance of neural and vascular homeostasis in the brain. The shape of the astrocyte is divided into soma and processes, and their shapes are known to change significantly in response to cerebral ischemia. However, it remains unclear how the ischemia changes the astrocytic shapes. In this work, we quantified the spatiotemporal dynamic changes in their morphologies during adaptation to hypoxia in in vivo mouse cortex. The cortical astrocyte labeled with sulforhodamine 101 was imaged with two-photon excitation fluorescence microscopy. The images were divided into the areas of astrocytic soma and processes, and reconstructed three-dimensionally. A volume of the soma and processes, a somatic circle degree and eccentricity, and a number and a length of the processes were calculated using custom-written Matlab software. We found the volume of the both astrocytic soma and processes significantly increased, and the soma become distorted from a spherical form with hypoxia in three weeks. The results indicate the simultaneous changes in the soma and process elicited by hyoxia.
