Investigation of the effects of intracameral carbachol on oxidative stress and apoptosis in rat corneas

PURPOSE: Our study aims to investigate the effects of intracameral carbachol on oxidative stress and apoptosis in rat corneas.
METHODS: In this experimental study, 28 Wistar albino male rats were used. There were 9 rats in the carbachol group, 9 in the balanced salt solution (BSS) group, and 10 in the sham group. The carbachol group was injected with 0.01 cc of carba-chol, and 0.01 cc of BSS was injected intracamerally into the BSS group. No drug was injected into the sham group, but the anterior chamber was entered with an empty syringe. Blood serum samples and corneas of rats were taken 1 week later. Caspase-3 and caspase-8 were immunohistochemically examined in rat corneal endothelial to investigate apoptosis. To determine oxidative stress in corneal endothelial tissue and serum, total antioxidant status (TAS), total oxidant stress (TOS), oxidative stress index (OSI), arylesterase (ARES), and paraoxonase (PON) levels were measured.
RESULTS: The mean OSI values in the rat serum of the carbachol group were significantly lower than those of the sham and BSS groups (P = 0.05 and P = 0.004, respectively). The mean TOS value of the carbachol group’s rat serum was significantly lower than the mean of the BSS group (P = 0.001). There was no significant difference in the mean TAS, TOS, OSI, ARES, and PON levels from the rat cornea of the carbachol, BSS, and sham groups (P > 0.05). All corneas in the carbachol group were caspase-3 negative, and a statistically significant difference was found among the sham, BSS, and carbachol groups (P = 0.002). No significant difference was observed among the sham, BSS, and carbachol corneas in caspase-8 staining (P = 0.094).
CONCLUSION: Our study demonstrates that intracameral carbachol is a safe intracameral drug. Carbachol reduced oxidative stress in rat serum compared to rats injected with BSS and the sham group. In addition, carbachol did not increase oxidative stress in rat corneas compared to the BSS and sham groups. Similarly, immunohistochemical examination showed that car-bachol did not increase apoptosis in rat corneas and had a protective effect.