Muscarinic Receptor Agonists Protect Cultured Bovine Trabecular Meshwork Cells against Apoptosis Induced by Dexamethasone

Purpose:To study whether muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone.Methods:The third to fifth passags of bovine trabecular meshwork cells were grown to confluence and incubated for 1-14 days in growth media with dexamethasone or pretreatment of pilocarpine or carbachol.The cultures were evaluated for apoptosis by phase-contrast microscopy, fluorescence microscopy, DNA laddering and flow cytometric analysis.Results:Dexamethasone (0.24-0.96 mmol·L^-1) induced apoptosis of trabecular meshwork cells in a dose and time-dependent manner.Before 0.48 mmol·L^-1 dexamethasone-treatment, 1.84 mmol·L^1 of pilocarpine or 2.74 mmol·L^-l of carbachol added could significantly reduce apoptotic percentage.Conclusion: Muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone.