Korean Journal of Nephrology 1998;17(5):673-678.

사람 근위세뇨관 세포에서 고밀도지단백의 Endothelin-1 분비 효과에 대한 칼슘통로차단제의 영향 (Effect of Calcium Channel Blockers on Endothelin-1 Production by HDL in Cultured Human Proximal Tubular Cells)

안선호, 송주홍 (Seon Ho Ahn and Ju Hung Song)

Abstract

Background
Human high density lipoprotein (HDL) is known to stimulate endothelin-1(ET-1) production through the phospholipase C(PLC)/Ca2＋/ protein kinase C(PKC) pathway. Calcium channel blockers may be involved in the decrease of HDL- induced ET-1 production. This study was designed to evaluate whether HDL-induced ET-1 production was affected by Ca2＋ channel blockers in cultured human proximal tubular cells(PTC).
Methods
The human PTC were obtained from human nephrectomized tissues, and cultured in six different media, which were bovine serum free(SF) DMEM/F12 medium alone, and five other SF DMEM/F12 media with 200μg/ml of HDL, with 200μg/ml of HDL and each 10μM of diltiazem, nifedipine, and verapamil solved in 100% ethanol 0.1 volume%, and with 200μg/ml of HDL and 0.1 volume% of 100% ethanol as a control. After 24 hours of exposure, ET-1 in the supernatant was measured by radioimmunoassay, and ET-1 level in each well were marked as pg ET-1/mg cell protein/ 24 hr in consideration of cell count.
Results
In SF medium, ET-1 production was 1.803±0.295pg/mg cell protein/24 hr. In SF medium with 200μg/ml of HDL, ET-1 production significantly increased from 1.803±0.295 to 10.860±0.476 pg/mg cell protein/24 hr(P<0.05). In SF medium with 200μg/ml of HDL and 100% ethanol 0.1 volume%, ET-1 production significantly decreased from 10.860±0.476 to 6.700±1.273pg/mg cell protein/ 24 hr(P<0.05). In SF media with 200μg/ml of HDL and each 10μM of diltiazem, nifedipine, and verapamil solved in 100% ethanol 0.1 volume%, ET- 1 production was decreased from 6.700±1.273 to 4.043±1.550 by diltiazem(P<0.05), to 3.260±0.752pg/ mg cell protein/24 hr by verapamil(P<0.05), and to 4.414±1.567pg/mg cell protein/24 hr by nifedipine (P=0.067).
Conclusion
These results suggest that the HDL- induced ET-1 production in cultured human PTC was significantly decreased by diltiazem and verapamil, and it seemed to be decreased by nifedipine.