动物造模,药效评价,硒酸钠白内障 z-bio 2024-07-16 405

　　【 Modeling mechanism 】 After reaching the eye tissue lens through fluid circulation, selenite oxidizes the thiol groups of proteins, leading to the inhibition of Ca2+- ATPase. This causes a large accumulation of Ca2+- ATPase in the lens nucleus fibers, leading to the activation of calpain in the nucleus fibers, as well as the hydrolysis of β - crystallin and other crystallin proteins. Partially hydrolyzed crystallin becomes insoluble; On the other hand, selenite can also react with trace amounts of H2O2 in aqueous humor to generate various reactive oxygen species. These reactive oxygen species attack lens proteins and various amino acids, causing damage to lens proteins and cross-linking, forming insoluble high molecular weight products that aggregate on the lens, leading to lens opacity and selenium induced cataracts.

　　There are many reports on modeling methods in domestic and foreign literature, mostly using subcutaneous injection of sodium selenite into mice born about 10-14 days old, with a dose of 0.25-2.25mg per kilogram of body weight. If injected 15 days after birth, even increasing the dose cannot induce cataracts. According to reports, oral administration of sodium selenite solution can also induce cataracts in mice aged 6-10 days.

　　【 Model Characteristics 】 13 hours after injection, some experimental animals' crystalline lenses may undergo changes, manifested as posterior opacities beyond the edge of the posterior Y-shaped suture, small vacuoles in the equatorial posterior capsule, and slight opacities. After 16 hours and 1 day of observation, the above changes were observed in all experimental animals. After 10 days, 80% of the offspring mice developed cataracts.

　　[Model Evaluation and Application] Oral administration has a first pass effect, and the dosage is difficult to accurately control, resulting in poor comparability of results. Subcutaneous administration is recommended. The formation of selenium induced cataracts is closely related to the interaction between intracellular free radicals and the antioxidant system, and can be used to study age-related cataracts and evaluate drug treatment efficacy.