Published online Sep 15, 2000. doi: 10.3748/wjg.v6.iSuppl3.108
Revised: June 28, 2000
Accepted: July 10, 2000
Published online: September 15, 2000
AIM: To determine NO, NO synthase (NOS) and NOSmRNA of the esophageal carcinoma cells (SHEEC1) in apoptotic process induced by As2O3 and to explore the relationship between NO and apoptosis.
METHODS: The apoptosis of the cell line (SHEEC1) was induced by arsenite (As2O3, 5 μmol/L and 10 μmol/L). In the process, at 2 h, 4 h, 8 h, 16 h and 24 h after administration of As2O3, NO production in cultural medium was detected quantitatively by spectrophotometry; NOSII was detected by immunohistochemistry and NOS mRNA by in situ hybridization (ISH). The cells at endpoint of the experiment were examined under transmitted electron microscope (TEM) for apoptosis.
RESULTS: The amount of NO released from SHEEC1 were increased from the basal condition (0.68 × 10-2μmol/L) up to the high level (2.38 × 10-2μmol/L) at h 16. The increment of NOSII was found after administration of As2O3; the intracytoplasmic ISH signals of NOSmRNA in small size was found firstly at 4 h, and then became highly predominant. Apoptotic changes of SHEEC1 occurred at 24 h under TEM.
CONCLUSION: After administration of As2O3, NO released from cultured SHEEC1 cells was detected with increasing amount up to 16 h. The expression of NOSII and transcription of NOSmRNA are upregulated. The present findings suggest a concept that the NO may be a mediated and effective factor in apoptosis induced by As2O3.