[The pathway of bFGF induced changes of calcium in cultured human lens epithelial cells]

To investigate the pathway of basic fibroblast growth factor (bFGF) induced changes of calcium in a human lens epithelial cell line LEC-B3.

The 3rd passage of LEC-B3 cells was used in the present studies. bFGF (10 microg/L), caffeine (10 mmol/L), ryanodine (10 mmol/L), procaine (50 mmol/L) and genistein (0.5 mmol/L) were added to the culture medium. Changes of calcium concentration were observed and analyzed with laser scanning confocal microscope.

bFGF (10 microg/L) could induce a prompt increase of calcium concentration when cells culturing in culture medium with or without calcium. No obvious difference of calcium concentration could be observed between these two conditions except that the amplitude of increase of calcium concentration under calcium free solutions was slightly higher than that in medium with calcium. Both 50 mmol/L procaine and 10 mmol/L ryanodine partially inhibited the calcium increase induced by bFGF. After the addition of 10 mmol/L caffeine, 10 microg/L bFGF could not induce a significant increase of calcium. Genistein at 0.5 mmol/L significantly inhibited bFGF induced changes of calcium.

bFGF inducing calcium ion concentration increase mainly depends on TPK pathway. Most of the calcium ions come from the release of intracellular calcium pools in human lens epithelial cell. Both the IP(3R) and RyR take part in the action, while IP(3R) is the more important factor.