TY - JOUR
T1 - NOx generation by cultured small intestinal epithelial cells
AU - Dignass, Axel U.
AU - Podolsky, Daniel K.
AU - Rachmilewitz, Daniel
PY - 1995/9
Y1 - 1995/9
N2 - The effect of cytokines, growth factors, mitogens, and bacterial products on nitric oxide (NO) generation by monolayers of small intestinal epithelial cells-6 (IEC-6) cells was evaluated. Subconfluent IEC-6 cells were maintained in DMEM containing 5% fetal calf serum and after 16-24 hr of incubation, the medium was replaced with fresh medium in the presence or absence of calcium ionophore (CaI), l-NAME, l-NNA, individual growth factors, cytokines, or mitogens. After 72 hr of culture, the media supernatant was collected and NOx generation was determined. NO synthase activity was determined in sonicated supernatants of IEC-6 cells by [14C] arginine conversion to citrulline. NOx generation in subconfluent cultures was greater than in fully confluent cultures, suggesting contact inhibition. NOx generation by IEC-6 cells was significantly increased by CaI and inhibited by l-NAME and l-NNA. LPS, IL-1β, IL-2, IL-8, IFN-8, TFN-α, EGF, TGF-α, bFGF, and PHA significantly increased NOx generation. NO synthase activity in IEC-6 cells (4.2±1.7 pmol/min/106 cells) was NADPH dependent. These results suggest that stimulation of NOx generation by intestinal epithelial cells through cytokine bacterial products and mitogens may be one of the mechanisms responsible for their effects in the intestinal tract.
AB - The effect of cytokines, growth factors, mitogens, and bacterial products on nitric oxide (NO) generation by monolayers of small intestinal epithelial cells-6 (IEC-6) cells was evaluated. Subconfluent IEC-6 cells were maintained in DMEM containing 5% fetal calf serum and after 16-24 hr of incubation, the medium was replaced with fresh medium in the presence or absence of calcium ionophore (CaI), l-NAME, l-NNA, individual growth factors, cytokines, or mitogens. After 72 hr of culture, the media supernatant was collected and NOx generation was determined. NO synthase activity was determined in sonicated supernatants of IEC-6 cells by [14C] arginine conversion to citrulline. NOx generation in subconfluent cultures was greater than in fully confluent cultures, suggesting contact inhibition. NOx generation by IEC-6 cells was significantly increased by CaI and inhibited by l-NAME and l-NNA. LPS, IL-1β, IL-2, IL-8, IFN-8, TFN-α, EGF, TGF-α, bFGF, and PHA significantly increased NOx generation. NO synthase activity in IEC-6 cells (4.2±1.7 pmol/min/106 cells) was NADPH dependent. These results suggest that stimulation of NOx generation by intestinal epithelial cells through cytokine bacterial products and mitogens may be one of the mechanisms responsible for their effects in the intestinal tract.
KW - epithelial cells
KW - nitric oxide
KW - small intestine
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U2 - 10.1007/BF02208647
DO - 10.1007/BF02208647
M3 - Article
C2 - 7555434
AN - SCOPUS:0028971749
SN - 0163-2116
VL - 40
SP - 1859
EP - 1865
JO - Digestive Diseases and Sciences
JF - Digestive Diseases and Sciences
IS - 9
ER -