A hypo-osmotically induced increase in intracellular Ca2+ in lactating mouse mammary epithelial cells involving Ca2+ influx

被引:20
作者
Sudlow, AW [1 ]
Burgoyne, RD [1 ]
机构
[1] UNIV LIVERPOOL, PHYSIOL LAB, LIVERPOOL L69 3BX, MERSEYSIDE, ENGLAND
来源
PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY | 1997年 / 433卷 / 05期
关键词
intracellular calcium; hypo-osmolarity; mammary cells;
D O I
10.1007/s004240050321
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
Using a fluorescent Ca2+-sensitive dye, we studied the effect of hypo-osmotic stress on the intracellular free Ca2+ concentration ([Ca2+](i)) in acini freshly isolated from lactating mouse mammary gland. The basal [Ca2+](i) of mammary acini was unaffected by a 50% (v/v) dilution of suspensions with isotonic or hypertonic buffer, or after ionic (iso-osmotic) dilution (external Ca2+ was 3 mM). Hypo-osmotic dilution (50%) elicited a rapid increase in [Ca2+](i) comprising a large, transient elevation, followed by a maintained plateau phase. No hypo-osmotically induced rise in [Ca2+](i) was observed in the absence of extracellular Ca2+. Neither microtubule disassembly using nocodazole nor actin disruption with cytochalasin D prevented hypo-osmotically evoked stimulation of [Ca2+](i). Pre-incubation of acini with nifedipine did not prevent hypo-osmotically induced stimulation of [Ca2+](i), whereas a non-specific cation channel blocker, gadolinium, partially inhibited the increases in [Ca2+](i) induced by hypo-osmotic stress. Furthermore, the transient component was still apparent, and not diminished in magnitude, after [Ca2+](i) had been elevated by mobilisation of Ca2+ from intracellular stores using thapsigargin. The results demonstrate that hypo-osmotic stress generates an increase in [Ca2+](i) in lactating mammary epithelial cells, the major, transient component of which appears to be due to influx of extracellular Ca2+.
引用
收藏
页码:609 / 616
页数:8
相关论文
共 45 条
[41]  
WILDE CJ, 1996, IN PRESS MAMMARY DEV
[42]   CALCIUM MOBILIZATION AND EXOCYTOSIS AFTER ONE MECHANICAL STRETCH OF LUNG EPITHELIAL-CELLS [J].
WIRTZ, HRW ;
DOBBS, LG .
SCIENCE, 1990, 250 (4985) :1266-1269
[43]   ROLE OF INTRACELLULAR CALCIUM IN CELLULAR-VOLUME REGULATION [J].
WONG, SME ;
CHASE, HS .
AMERICAN JOURNAL OF PHYSIOLOGY, 1986, 250 (06) :C841-C852
[44]  
YAMAGUCHI DT, 1989, J BIOL CHEM, V264, P4383
[45]   EFFECTS OF INOSITOL 1,4,5-TRISPHOSPHATE ON CALCIUM RELEASE FROM THE ENDOPLASMIC-RETICULUM AND GOLGI-APPARATUS IN MOUSE MAMMARY EPITHELIAL-CELLS - A COMPARISON DURING PREGNANCY AND LACTATION [J].
YOSHIMOTO, A ;
NAKANISHI, K ;
ANZAI, T ;
KOMINE, S .
CELL BIOCHEMISTRY AND FUNCTION, 1990, 8 (04) :191-198