Real-time imaging of viable-apoptotic switch in GSNO-induced mouse thymocyte apoptosis.
Many scientists are focusing on the apoptotic-necrotic or the necrotic-apoptotic switch and its mechanism, but little attention has been paid to the viable-apoptotic switch. Most of the techniques and methods used for detecting apoptosis are performed on fixed samples, yielding static information of specific time points. We have studied the viable-apoptotic switch in S-nitrosoglutathione (GSNO)-induced mouse thymocyte apoptosis in real-time by means of a novel technique, intensified charge coupled device (ICCD)-based real-time fluorescence micro-imaging, coupled with Annexin V-FITC labeling for phosphatidylserine (PS) translocation in cell membrane. We have successfully recorded the initiating time points (mostly at 2 h) of the viable-apoptotic switch in GSNO-initiated apoptosis, as well as shown the real-time differences between living and apoptotic thymocytes. These findings suggest that NO is also a switch molecule for the conversion from viable to apoptotic cell. Thymocytes cotreated by N-G-monomethyl-L-arginine acetate salt (L-NMMA) provide further evidence for this suggestion, as well as for the suggestion that L-NMMA prolongs the early stage of thymocyte apoptosis rather than strongly blocks it.
Lin
Dan-ying
DY
Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry, Department of Physics, Tsinghua University, Beijing 100084, China.
Ma
Wan-yun
WY
Duan
Shao-jin
SJ
Zhang
Yan
Y
Du
Li-ying
LY
D000818:Animals; D017304:Annexin A5 / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects*; D005434:Flow Cytometry / Q000379:methods; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence / Q000379:methods*; D026422:S-Nitrosoglutathione / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects*; D019323:omega-N-Methylarginine / Q000494:pharmacology
D017304:Annexin A5; D019323:omega-N-Methylarginine; D026422:S-Nitrosoglutathione; D016650:Fluorescein-5-isothiocyanate