A study on changes of liver and salivary glands in rats with experimentally induced liver injuries. Pathological and biochemical observations]

Changes in the salivary glands, liver and pancreas in rats with experimentally induced liver injuries were examined. The injuries (experimental group) were induced by subcutaneous injections of carbon tetrachloride (0.01ml/kg body weight) in a 50% olive-oil solution. The injections were administered twice weekly for 10,20 and 40 weeks. Control animals received the same doses of olive oil during the same periods. 1. In the experimental group, serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) increased remarkably, whereas serum albumin decreased. 2. Swelling of the liver and multiple nodular formations occurred in the experimental group. Liver fibrosis with the formation of pseudolobules indicated a form of liver cirrhosis. 3. No significant histological changes were observed in the pancreases of animals in the 10- and 20-week experimental groups. Vacuolation in the acinar cells was observable in 3 of 8 cases in the 40-week experimental group. 4. In connection with histological findings of parotid glands, vacuolation of the acinar cells occurred in 7 of 12 cases in the 10-week experimental group, in 7 of 8 cases in the 20-week experimental group, and in all 8 cases in the 40-week experimental group. Vacuole numbers and sizes increased as the experimental period was prolonged. 5. Immunohistochemical investigation showed strong positive reactions to the anti-amylase antibody around vacuoles in acinar cells of parotid glands. In unvacuolated acinar cells, on the other hand, only slight positive reaction was observed. 6. Electronmicroscopic observation of the acini revealed greatly enlarged lumina and dilated intercellular canaliculi connected to the lumina. Small vacuoles were observed on the basement of the acini. 7. No such significant changes as fibrosis, vacuolation, and atrophy of acinar cells were observed in the submandibular and sublingual glands of the experimental animals. 8. Serum amylase activity increased more in the experimental than in the control rats. Electrophoretic patterns suggested that in the control group 95 percent of serum amylase was parotid type, and also in the experimental group 95 percent of serum amylase was parotid type. 9. Amylase activity in the parotid glands also increased more in the experimental than in the control animals.