|
KMID : 0811720170210020233
|
|
Korean Journal of Physiology & Pharmacology
2017 Volume.21 No. 2 p.233 ~ p.239
|
|
|
Hydrogen peroxide attenuates refilling of intracellular calcium store in mouse pancreatic acinar cells
|
|
Yoon Mi-Na
Kim Dong-Kwan
Kim Se-Hoon
Park Hyung-Seo
|
|
|
Abstract
|
|
|
|
Intracellular calcium (Ca2+) oscillation is an initial event in digestive enzyme secretion of pancreatic acinar cells. Reactive oxygen species are known to be associated with a variety of oxidative stress-induced cellular disorders including pancreatitis. In this study, we investigated the effect of hydrogen peroxide (H2O2) on intracellular Ca2+ accumulation in mouse pancreatic acinar cells. Perfusion of H2O2 at 300 μM resulted in additional elevation of intracellular Ca2+ levels and termination of oscillatory Ca2+ signals induced by carbamylcholine (CCh) in the presence of normal extracellular Ca2+. Antioxidants, catalase or DTT, completely prevented H2O2-induced additional Ca2+ increase and termination of Ca2+ oscillation. In Ca2+-free medium, H2O2 still enhanced CCh-induced intracellular Ca2+ levels and thapsigargin (TG) mimicked H2O2-induced cytosolic Ca2+ increase. Furthermore, H2O2-induced elevation of intracellular Ca2+ levels was abolished under sarco/endoplasmic reticulum Ca2+ ATPase-inactivated condition by TG pretreatment with CCh. H2O2 at 300 μM failed to affect store-operated Ca2+ entry or Ca2+ extrusion through plasma membrane. Additionally, ruthenium red, a mitochondrial Ca2+ uniporter blocker, failed to attenuate H2O2-induced intracellular Ca2+ elevation. These results provide evidence that excessive generation of H2O2 in pathological conditions could accumulate intracellular Ca2+ by attenuating refilling of internal Ca2+ stores rather than by inhibiting Ca2+ extrusion to extracellular fluid or enhancing Ca2+ mobilization from extracellular medium in mouse pancreatic acinar cells.
|
|
|
KEYWORD
|
|
|
Hydrogen peroxide, Intracellular Ca2+ stores, Pancreatic acinar cells, Reactive oxygen species, Sarcoplasmic reticulum Ca2+ ATPase
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
  
|