Effect of Cholinergics on the Survival and Production of Nitric Oxide in Cultured Ciliary Muscle Cells

ABSTRACT

PURPOSE: To investigate the effect of cholinergics on the survival and production of nitric oxide (NO) in the cultured ciliary muscle cells. METHODS: Primarily cultured porcine ciliary muscle cells were exposed to the pilocarpine and to the atropine at various concentrations for 24 hours. The cellular survival was assessed by rapid colormetric assay (MTT assay) and the production of nitrite was measured by Griess reaction. NO production was measured after co-administration of pilocarpine and atropine. RESULTS: Cultured ciliary muscle cells expressed alpha-smooth muscle actin. Both pilocarpine and atropine did not affect the cellular survival (p>0.05). Pilocarpine decreased the production of NO significantly from 10 micro M (p<0.05). Atropine increased NO production from 1 micro M and inhibited pilocarpine-induced inhibition of NO production. CONCLUSIONS: Pilocarpine decreases the production of NO that abolished by atropine in the ciliary muscle cells. Pilocarpine may constrict the ciliary muscle by inhibiting production of NO and decrease uveoscleral outflow subsequently.