动物造模 z-bio 2022-06-17 323

　　Objective To observe the chronic toxicity of Deinococcus radiodurans R1 to SD rats.

　　Methods High concentration (109/mL, LDRH group) and low concentration (107/mL, LDRL group) of DRR1 viable bacteria and high concentration (109/mL, BDRH group) and low concentration (107/mL, BDRL group) were used. Bacterial fragments were administered to SD rats at a dose of 1 mL/100 g body weight, and the same volume of TGY agar medium (containing 0.5% tryptone, 0.1% glucose and 0.3% yeast extract) was administered as a control group. (TGY group); 16 animals in each group, half male and half male, were given intragastric administration once a day for 30 consecutive days. 8 rats were randomly selected from each group and anesthetized by intraperitoneal injection of 3% pentobarbital sodium 0.15 mL/100 g body weight. The main organs were fixed with 10% neutral formaldehyde solution, stained with HE, and the pathological changes were observed under a light microscope. The remaining 8 rats in each group were treated in the same way 14 days after drug withdrawal, and the delayed toxicity of DRR1 was observed. During the experiment, the behavior, food intake and body weight of the rats were observed.

　　Results After 30 days of administration of DRR1 live bacteria and DRR1 fragments of different concentrations, immediately after drug withdrawal and 14 days after drug withdrawal, no abnormal movement and breathing of rats in each group were observed, and no unresponsiveness, pupil changes, and bulging eyes were observed. Abnormal phenomena such as vaginal discharge and skin color change, no abnormal secretions were found in the mouth, ears, nose and canthus of the eyes, and the defecation and shape were normal; there was no significant change in food intake, body weight changes and organ coefficients compared with the TGY group; the number of white blood cells Significantly decreased on 30 days of administration (P<0.05), and returned to normal levels after 14 days of drug withdrawal; no significant changes in the number of red blood cells, hematocrit and hemoglobin, and the number and percentage of lymphocytes, granulocytes, and monocytes There was no significant change, nor was there a significant change in platelet count. Serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein (TP), uric acid (UA), urea (UREA), blood glucose (Glu), magnesium (Mg) and phosphorus (P) immediately after drug discontinuation There was no significant change in the content of serum aspartate aminotransferase (AST), creatine kinase (CK), creatine kinase isoenzyme (CK-MB) and lactate dehydrogenase (LDH) in the LDRH group were significantly increased (P<0.05); After the 14-day recovery period, AST and CK decreased to the level of the recovery period TGY group, and CK-MB was still higher than that of the recovery period TGY group (P<0.05). 30="" and="" there="" was="" no="" significant="" difference="" compared="" with="" the="" tgy="" group="" in="" recovery="" period.="" control="" serum="" ion="" concentration="" did="" not="" change="" significantly="" among="" groups="" at="" d="" of="" administration="" p="">0.05); after 14 days of drug withdrawal, the serum Cl- and Ca2+ in the LDRH group decreased, while the Na+ and pH values increased. (P<0.05); no obvious substantial lesions were found in the pathological observation of the heart, liver, lung and kidney.

　　Conclusion DRR1 live bacteria and its bacterial fragments have no actual toxicity to rats, and this experiment provides experimental data for the expansion of DRR1 applications.