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3D Random Rotations Induce Apoptosis In Cultured Astrocytes      M.A.  Masini¹, B. Uva^1, F. Strollo², P. Prato¹ and F. Ricci³,  ¹Dipartimento di Biologia, Università di Genova;  ²Unita’ Endocrinologia INRCA &  Università di Roma “La Sapienza”; ³ENEA C.R. Casaccia Roma, Italy.

   Macroglia (oligodendrocytes plus astrocytes)  is a fundamental component of the nervous system. It is well known that glia fulfills supporting and nutritional roles to the neurons. More recently a new insight in the interaction between glia and neurons have revealed the pivotal role carried out by astrocytes (the major type of glia in the brain) in neurogenesis, synaptic formations and maintenance of the synaptic efficiency. Therefore a damage at astrocytes level results in alterations of large areas of the brain. Low gravity, real and in on ground conducted experiments, induces alterations in lymphocytes and macrophages (Cogoli-Greuter et al., 1998) and astrocytes (Uva et al., 2000) in the microtubules, impairing cell division and intracellular organelles, and in the microfilaments altering cell shape and cell adhesion. Real and modelled microgravity are therefore an environmental stress that causes apoptosis. Aim of the present work was to investigate on the onset of apoptosis in astrocytes cultered in medium with or without addition of calcium, kept in continous rotation in a desktop 3D RPM for 15 min, 30 min, 1h, 3h and 24h. At the end of the rotations the cells were detached from some cultures and submitted to Western Blotting in order to evidentiate the following proteins: f-actin, Bax, Bcl2 and caspase 3. Cells from other cultures were fixed and submitted to immunohistochemistry using the antisera Ab-caspase 7and Ab-a tubulin. F-actin was visualised with Phalloidin. DNA fragmentation was detected with TUNEL method. The results indicated that RPM rotations induce apoptosis within 1 h of treatment. Apoptosis inhibitors were present in the cells cultured in presence of calcium ions.