Abstract
To examine the morphological changes of HL-60 cells undergoing apoptosis, we induced apoptosis by etoposide treatment, and compared the findings obtained with an electron microscopic cytochemical method with those obtained with in situ end-labeling (ISEL) of DNA and a DNA fragmentation assay. Apoptotic cells were detected by ISEL of DNA 1h before the ladder formation in the DNA fragmetation assay, and an accumulation of DNA was observed simultaneously around the nucleoli and nuclear membrane by DNA-staining electron microscopy. These findings revealed that the apoptosis-related changes occurred in the DNA before the appearance of ladder formation. DNA staining with osmium ammine B revealed, at higher magnification, a rough fiber formation of DNA before apoptosis and an accumulation of small particles with the course of apoptosis. The number of primary granules stained for peroxidase in the cytoplasm decreased as apoptosis progressed. An examination by the periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) method revealed in number after the induction of apoptosis. Thus, apoptosis-related changes were observed not only in the nucleus but also in the cytoplasm.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
