Abstract
Abstract: :
Purpose:To investigate the effects of exogenous plasmin on the activity of endogenous matrix metalloproteinase (MMP) –2 in vitreous cavity. Methods:Plasmin purified from human serum (0.1, 0.5, and 1.0 IU) was injected into the rabbit eyes. 15 min after injection, the vitreous sample was collected by pars plana vitrectomy. In the same manner, the vitreous sample was collected at 15, 30, 120, and 360 min after 1.0 IU of plasmin injection. Human vitreous samples from 5 eyes of 5 patients with macular hole were also collected before and 15 min after plasmin injection. The active–/pro–MMP–2 ratio were calculated by the data of gelatin zymography from each sample. Results:In control, the active–/pro–MMP–2 ratio was 0.101 ± 0.042. The results of active–/pro–MMP–2 ratio in the vitreous after 0.1 IU, 0.5 and 1.0 IU of plasmin injection were 0.202 ± 0.059, 0.268 ± 0.046, and 0.273 ± 0.042, respectively. The results of 0.5 IU and 1.0 IU were significantly higher than that of control. The results of active–/pro–MMP–2 ratio in the vitreous at 15, 30, 120 and 360 min after 1.0 IU of plasmin injection were 0.273 ± 0.042, 0.119 ± 0.014, 0.091 ± 0.014, and 0.096 ± 0.012, respectively. There was significant difference between 15 min after plasmin injection and control. In human samples, the active–/pro–MMP–2 ratio after plasmin injection was significantly higher than the ratio before plasmin injection. (p = 0.0013) Conclusions:The present study indicated that endogenous MMP–2 in the vitreous was significantly activated by the administration of exogenous plasmin.
Keywords: vitreous • detection • drug toxicity/drug effects