Microgravity is one of the crucial factors in space that impact the healthy and work efficiency of astronauts. Therefore extensive research on the effects of microgravity or simulated microgravity on both human and animals has been carried out. The present study investigates whether simulated microgravity could influence the morphology and apoptosis of hippocampal tissue blocks and primary cells. Tissue blocks and primary cells are obtained from fresh hippocampus of neonatal SD rats. After being cultured for 7 days at 37℃, 95% of humidity and 5% CO2, cultures are randomly divided into a control group and a simulated microgravity group. The microgravity group is exposed to clinostat for one day and the control group is cultured on the same horizontal line of the clinostat. Then, microscope and HE staining are used to observe the surface morphology and internal morphology. In addition, apoptosis is measured by flow cytometry. As shown in the results, after treatment with 1-day simulated microgravity, the edge of tissue blocks becomes thinner and the cells within tissue blocks distribute in disorder, as compared to the control group. But apoptosis of primary cells show no difference between the simulated microgravity group and the control group. It is indicated that there is significant morphological difference of tissue blocks between the two groups after short-term simulated microgravity. However, apoptosis of primary cells seems not being affected by short-term simulated microgravity at all.

simulated microgravity  /  hippocampus  /  morphology  /  apoptosis