[Direct measurement of nitric oxide levels in aqueous humor with selective iso-NO electrode under physiologic conditions and after phacoemulsification and artificial acrylic lens implantation in experiments on rabbits].

PURPOSE

Using a direct method, with selective and nitric oxide sensitive electrode Iso-NO, we estimated the level of the Nitric Oxide (NO) in the aqueous humor of the rabbit's eye after phacoemulsification and acrylic foldable lens implantation. We also analysed the NO level during early postoperative days between the 1st and the 5th postoperative day. The current methods of the NO level estimations are also considered.

MATERIAL AND METHODS

We examined 30 gray rabbits (weighing 3.0-3.5 kg). Just before surgery, samples of aqueous humor were aspirated. Lens was extracted with phacoemulsification technique. In 15 eyes acrylic foldable IOL was implanted and 15 eyes were left aphacic. The aqueous samples were collected 1, 3, 5 days after surgery. Nitric oxide in each sample was determined with direct, selective nitric oxide sensitive electrode Iso-NO. Because of changing values of the NO concentration and its characteristic course, we expressed the concentration of NO in aqueous humor using field-under-curve method to compare it with control group. The results of our examination are presented in the absolute values.

RESULTS

During physiological conditions the mean value of the field under curve of the NO concentration was estimated as 4987.29 +/- 895.89. After phacoemulsification with or without artificial lens implantation the level of the NO was higher as compared to the control group. After phacoemulsification and acrylic foldable lens implantation the highest level of NO was estimated on the 1st postoperative day as 6917.10 +/- 1199.72. During the examinations, the field under curve of NO concentration was estimated as 6246.63 +/- 327.02 and 5172.28 +/- 552.67 (on the 3rd and 5th days respectively). Only on the 1st and the 3rd postoperative day, the value of the field under curve of NO was significantly higher as compared with the control group. In contrast, after phacoemulsification without lens implantation the highest value of NO field under curve, was estimated on the 3rd postoperative days as 5801.44 +/- 344.45. During the examinations, the field under curve of NO concentration was estimated as 5115.30 +/- 796.11 and 4837.12 +/- 205.87 (on the 1st and the 5th days, respectively). Moreover, it was the only one day of examination with significantly higher value of NO field under curve as compared with the control.

CONCLUSION

We came to conclusion that the level of nitric oxide in aqueous humor after phacoemulsification with or without artificial lens implantation is higher than in control group. The highest value of the field under curve was estimated on the 1st postoperative day after phacoemulsification and acrylic foldable lens implantation and on the 3rd postoperative day after phacoemulsification without lens implantation.