Muscarinic receptor agonists protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone.

ABSTRACT

PURPOSE: To study whether muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone. METHODS: The third to fifth passages 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-1 of carbachol added could significantly reduce apoptotic percentage. CONCLUSION: Muscarinic receptor agonists can protect cultured bovine trabecular meshwork cells against apoptosis induced by dexamethasone.