ABSTRACT
Objectives: To evaluate possible ocular hypotensive effect of 0.5% diltiazem and 0.1% verapamil eye drops on intraocular pressure in steroid induced glaucoma model of rabbits. And compare with 0.5% timolol eye drops. Methodology: Glaucoma was induced in rabbits (N=18) by bilateral topical instillation of 1% prednisolone eye drop (10 μl) twice a day for a period of 40 days. Before the induction of glaucoma, baseline intraocular pressure (IOP) in both the eyes of all rabbits was measured under sedation (i.v midazolam) by Schiotz tonometer. At the end of 40 days induced IOP was measured for all rabbits and rabbits were divided into three groups of six rabbits in each. Right eyes of group A, B and C rabbits received 0.5% diltiazem, 0.1% verapamil, and 0.5% timolol eye drops twice daily for 12 days respectively. Whereas, left eyes of all rabbits received distilled water hence represented as control. IOP was measured in all rabbits on every 4th day till 12 days of treatment period. Results: Intra-group comparisons of IOP changes were made by paired‘t’ test. And unpaired‘t’ test for inter group comparisons. One way ANOVA was used for multiple group comparisons followed by post-hoc Tukey’s test for group wise comparisons. In 0.5% diltiazem treated eyes, the mean IOP significantly reduced from 22.9±1.9 mmHg (10%) on 4th day to 16.9±1.1 mmHg(S, P<.001) on 12th day (34%). Similarly, mean IOP in 0.1% verapamil treated eyes significantly reduced from 22.7±1.3 mmHg (7%) on 4th day to 15.5±1.4 mmHg(S, P<.001) on 12th day (37%). Whereas, mean IOP significantly reduced from 22.4±1.9 mmHg (14%) on 4th day to 16.4±1.4 mmHg (S, P=.001) on 12th day (36%) in 0.5% timolol treated eyes. Conclusion: Topical 0.5% diltiazem and 0.1% verapamil significantly reduced the IOP in steroid induced glaucoma model of rabbits. However, Further research has to be carried out both in experimental and clinical subjects to reveal its efficacy and safety profile.
ABSTRACT
Background: The glutamate system has been implicated in depression recently. This is a departure from previous thinking, which had focused on serotonin and norepinephrine. The glutamate system may represent a new avenue for treatment and research. NMDA and AMPA are receptors for the neurotransmitter glutamate. Blocking NMDA increases the activity of another receptor, AMPA, and this boost in AMPA activity is crucial for rapid antidepressant actions. Amantidine being a noncompetitive antagonist at NMDA receptor is evaluated for its antidepressant activity in this study. Objectives: To evaluate the antidepressant activity of amantidine and compare it with Imipramine in albino mice. Methodology: Total of 18 swiss albino male mice were used. They were divided into three treatment groups and with normal saline (control) 10mg/kg, Imipramine (standard) 10mg/kg and amantidine 26 mg/kg (test drug) given orally. Each group contained 6 animals. Duration of immobility was observed for 6 minutes in tail suspension test and for 4 minutes in forced swimming test on separate set of animals. Results: Results were analyzed by ANOVA followed by Post hoc Tukey’s test. Amantidine at the dose of 26 mg/kg significantly reduced the immobility time in both the tests compared to control (p < 0.05). Conclusion: Non-competative antagonist, amantidine has significant antidepressant activity in acute models of depression.