【Animal Modeling】-Blunted cataract model

  (1) Copy method After mydriasis, examine four-week-old female rats with a slit lamp to exclude corneal diseases, uveal diseases, lens and vitreous diseases. General anesthesia is performed by injecting a 10% chloral hydrate solution into the abdominal cavity at a dose of 3 ml/kg body weight. After placing the animal on the operating table, the left eye of the rat was patted with 20 grams of pellets from a height. 20 cm, once a week, 100 times each time, and then continue for several weeks.

  (2) Model characteristics Three days after the first impact, the experimental eyes of rats showed opacity of dots and flakes scattered on the anterior capsule of the lens, and circular opacity in the center of the pupil. On day 6, the scattered sheet-like opacity of the anterior capsule disappeared completely, but the annular and dendritic opacity of the anterior lens capsule near the central pupil area did not change. After repeated blows (2nd to 5th), the anterior capsule appeared repeatedly, with repetitive spots and sheet opacity, while the ring and dendritic opacity of the anterior lens capsule near the central pupil was 3, and the repair began. The capsular bag is made into an electron microscope sample. Observation under a transmission electron microscope revealed that typical apoptotic cells were loosely combined with neighboring cells, expanding the distance between cells, shrinking the cell body, and destroying the nuclear envelope. Chromatin condenses around the nuclear envelope, and the cytoplasm is concentrated and contains many vacuoles. Some vacuoles are denatured vacuoles, and some liquefied vacuoles, compared with normal, the number of mitochondria is reduced by more than 40%.

  (3) Comparative medicine Lens epithelial cells are the most active part of lens metabolism, providing basic materials and metabolic energy for the growth, differentiation and damage of the lens. The lens relies on the epithelial cell layer to maintain the metabolic balance and transparency of the entire lens. Changes in state or the influence of factors such as oxidative stimulation, radiation damage and trauma can threaten the survival of lens epithelial cells, cause lens opacity and induce cataracts. The cataract model replicated by this method repeatedly hits the eyes of the model rat, and after continuous observation for 5 weeks, the lens of the model animal may have clinical symptoms similar to human blunt contusive cataract. The lens looks like ring opaque and radial opacity, flaky opacity and spot opacity. This model is suitable for clinical research on the etiology of human blunt contusion cataract.