Effect of sertraline on Ca²⁺ fluxes in rabbit corneal epithelial cells

Chin J Physiol. 2015 Apr 30;58(2):85-94. doi: 10.4077/CJP.2015.BAC255.

Abstract

The effect of sertraline, a selective serotonin reuptake inhibitor (SSRI), on cytosolic free Ca²⁺ concentrations ([Ca²⁺](i)) in a rabbit corneal epithelial cell line (SIRC) is unclear. This study explored whether sertraline changed basal [Ca²⁺](i) levels in suspended SIRC cells by using fura-2 as a Ca²⁺-sensitive fluorescent dye. Sertraline at concentrations between 10-100 μM increased [Ca²⁺](i) in a concentration-dependent manner. The Ca²⁺ signal was reduced by 23% by removing extracellular Ca²⁺. Sertraline induced Mn²⁺ influx, leading to quench of fura-2 fluorescence, suggesting Ca²⁺ influx. This Ca²⁺ influx was inhibited by phospholipase A₂ inhibitor aristolochic acid, but not by store-operated Ca²⁺ channel blockers and protein kinase C/A modulators. In Ca²⁺-free medium, pretreatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin, cyclopiazonic acid or 2,5-di-tert-butylhydroquinone greatly inhibited sertraline-induced Ca²⁺ release. Inhibition of phospholipase C with U73122 abolished sertraline-induced [Ca²⁺](i) rise. At concentrations of 5-50 μM, sertraline killed cells in a concentration-dependent manner. The cytotoxic effect of 25 μM sertraline was not reversed by prechelating cytosolic Ca²⁺ with BAPTA/AM. Collectively, in SIRC cells, sertraline induced [Ca²⁺](i) rises by causing phospholipase C-dependent Ca²⁺ release from the endoplasmic reticulum and Ca²⁺ influx via phospholipase A₂-sensitive Ca²⁺ channels. Sertraline-caused cytotoxicity was mediated by Ca²⁺-independent pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Calcium Signaling / drug effects
  • Calcium Signaling / physiology*
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism*
  • Epithelium, Corneal / cytology*
  • Epithelium, Corneal / drug effects
  • Epithelium, Corneal / metabolism*
  • Rabbits
  • Selective Serotonin Reuptake Inhibitors / administration & dosage
  • Sertraline / administration & dosage*

Substances

  • Serotonin Uptake Inhibitors
  • Sertraline
  • Calcium