Nongenomic effects of aldosterone on Ca2+ in M-1 cortical collecting duct cells

被引:93
作者
Harvey, BJ [1 ]
Higgins, M [1 ]
机构
[1] Univ Coll Cork, Dept Physiol, Wellcome Trust Cellular Physiol Res Unit, Cork, Ireland
关键词
sex steroids; nongenomic pathway; M-1; cells; CCD cells; calcium signaling; protein kinase C; renal transport;
D O I
10.1046/j.1523-1755.2000.00981.x
中图分类号
R5 [内科学]; R69 [泌尿科学(泌尿生殖系疾病)];
学科分类号
1002 ; 100201 ;
摘要
Background. Aldosterone at physiological levels induces rapid (<5 min) increases in intracellular protein kinase C (PKC) activity and a rise in calcium and pH in mineralocorticoid hormone target epithelia, such as distal colon and sweat gland. The end targets of these rapid responses in epithelia are Na+/H+ exchange and K+ channels. Methods. The mouse cortical collecting duct (CCD) M-1 cell line was grown to confluency and loaded with Fura-2 for spectrofluorescence measurements of intracellular free calcium at 37 degrees C bathed in Krebs solution. Results. Aldosterone (1 nmol/L) produced a rapid, transient peak increase in [Ca2+](i) in M-1 cells. This effect was abolished upon removal of extracellular Ca2+, but was unaffected by pre treatment with spironolactone (10 mu mol/L) or actinomycin D (10 mu mol/L). However, pretreatment with the specific PKC inhibitor chelerythrine chloride (1 mu mol/L) prevented the aldosterone-induced rise in [Ca2+ ](i). Dexamethasone, at a concentration 10,000-fold higher than aldosterone (10 mu mol/L), also produced a transient increase in [Ca2+](i), but this response was significantly smaller than that of aldosterone. In contrast, hydrocortisone had no effect on [Ca2+](i) at either nmol/L or mu mol/L concentrations. Both of the sex steroids, 17 beta-estradiol (10 nmol/L) and progesterone (10 nmol/L), induced protein kinase C-dependent increases in [Ca2+](i). Conclusions. Aldosterone and sex steroid hormones activate intracellular calcium signaling in CCD cells via a nongenomic PKC-dependent pathway, which may have important implications for renal transport.
引用
收藏
页码:1395 / 1403
页数:9
相关论文
共 28 条