The viability of human lymphoblasts was investigated after compression
at 37 degrees C for 30 min. Immediately after decompression, necrotic
cells were observed and the viability decreased sigmoidally to 0 with
increasing pressure from 85 to 200 MPa. Apoptotic cells began to be o
bserved from 8 h after decompression in the case of compression at 100
MPa for 30 min at 37 degrees C. The apoptosis was confirmed to be pre
ssure-induced by the Tunel method and by optical and electron microsco
py. Cell death by both necrosis and apoptosis due to compression was a
ccelerated in the S phase of the cell cycle. (C) 1997 Academic Press.