[A study on cytokine levels and nitric oxide content in rabbit aqueous humor after lens extraction and intraocular lens implantation].

Objective: To investigate the relationship among inflammatory reaction and cytokine levels, nitric oxide (NO) content in aqueous humor after intraocular lens implantation.

Methods: Eighteen New Zealand rabbits were divided randomly into 3 groups (each 6 rabbits): (1) control group, (2) extracapsular cataract extraction group (ECCE) and (3) ECCE and posterior chamber intraocular lens implantation group (ECCE + IOL). The inflammation of all experimental rabbit eyes were observed by a zoom-photo slit-lamp microscope 0, 1, 3, 7, 14, 30 days postoperatively, including corneal edema and anterior chamber exudation. Meanwhile, aqueous humor was drawn for white blood cell (WBC) count and classification, as well as for NO(2)(-)/NO(3)(-) and cytokine assays, including interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha). Statistics were taken by SPSS software.

Results: (1) The anterior chamber exudation was the most serious and monocyte/macrophage in aqueous humor were the highest in ECCE + IOL group in postoperative 7 - 14 days. (2) The levels of IL-2, TNF-alpha and the content of NO(2)(-)/NO(3)(-) in aqueous humor of ECCE + IOL group were higher than that in ECCE group and control group in the postoperative 1 - 14 days respectively, and they increased to their peak values at the postoperative 3 - 7 days and decreased gradually after postoperative two weeks. (3) The change regularity of IL-2, TNF-alpha, NO(2)(-)/NO(3)(-) and inflammatory reaction in each group were basically similar, i.e. the more serious the reaction, the higher the levels of the contents.

Conclusion: The intraocular inflammation after intraocular lens implantation is closely related to the changes of cytokine levels and NO content in aqueous humor.