Study On The Pathological Mechanism Of Testicular Tissue Injury In Mice Induced By Ammonia

Ammonia(NH₃)is a colorless soluble substance.High concentration of ammonia will produce a pungent odor.After metabolism in animals,ammonia is one of the most important metabolic toxic products.In the process of animal husbandry and breeding,ammonia is one of the main harmful gases produced.Ammonia in the air can reduce the immunity of animals.Exogenous ammonia can cause different degrees of disease in animals.Endogenous ammonia will cause damage to internal organs and reproductive dysfunction after the circulation of various metabolic systems in the body.Ammonia gas has a destructive effect on the growth and reproduction of livestock and poultry,and will also cause certain pollution to the air.Although the effects of ammonia on respiratory tract and viscera have been described in different studies on the effects of ammonia on animal body,the harmful effects and biological mechanism of ammonia on testicular tissue of male animals are still unclear in the studies on the effects of ammonia on animal reproductive system.In order to explore the toxic effects of ammonia on male reproductive organs from multiple perspectives（inflammation,apoptosis,autophagy）,this experiment took mice as animal models,and divided 32model mice into ammonia group（ammonia concentration of 80 ppm）and normal control group（0 ppm）.The mice were killed on the 21st day,and testicular tissue was collected.In this experiment,H&E staining,immunohistochemistry,real-time fluorescence quantitative PCR,protein immunoblotting and other methods were used to examine the histopathology,inflammation,apoptosis and autophagy of mouse testicles under the influence of ammonia gas,so as to clarify the mechanism of animal reproductive toxicology caused by ammonia gas exposure.The results show that:1.The results of autopsy showed that ammonia exposure could lead to testicular shrinkage in mice,accompanied by significant shortening of testicular length;Compared with the normal control group,the nucleus in the testicular tissue of the mice exposed to ammonia gas became round,accompanied by the appearance of necrotic spermatogenic cells and interstitial fibrosis.The spermatogenesis was significantly reduced,and part of the testicular tissue had been damaged.There was edema in the interstitial tissue.The remaining spermatogenic tubules,although intact in structure,did not produce sperm cells,suggesting long-term exposure to ammonia gas,It can lead to testicular tissue damage and spermatogenesis decline in male animals.2.The positive rate of IL-10 immunohistochemistry in the testicular tissue of mice in the ammonia control group was significantly increased（P<0.05）.The ammonia gas will lead to an increase in the expression of inflammatory factors in the testicular tissue of mice,thus affecting normal physiological activities and reproductive health.3.Ammonia caused a decrease in the positive rate of immunohistochemistry of the apoptosis-inhibiting factor Bcl-2,while the fluorescence intensity of the immune tissue of the endogenous apoptotic gene Cyt C was significantly higher than that of the normal control group（P<0.05）.In the two control groups,the relative expression of protein and m RNA of pro-apoptosis factors p53,Caspase8,Bax,and Apaf1 were significantly higher than those of the normal group after the introduction of ammonia（P<0.01）,while the relative expression of m RNA of anti-apoptotic factor Bcl-2 was significantly lower than that of the normal group after the introduction of ammonia（P<0.05）,and the relative expression of protein was significantly lower than that of the normal group（P<0.01）.4.Ammonia caused the decrease of the immunohistochemical positive rate of autophagy inhibitor p62 in mouse testicular tissue;The fluorescence intensity of the autophagic factor LC3B was significantly increased（P<0.05）;The expression of autophagy promoting factors Beclin1,ATG5 and LC3B in the two control groups increased significantly after the introduction of ammonia（P<0.01）,while the relative expression of m RNA and protein of autophagy inhibiting factor p62 decreased significantly in the ammonia environment（P<0.01）.To sum up,this experiment has successfully established a mouse model of ammonia poisoning.The introduction of ammonia will significantly reduce the reproductive capacity of male mice,and increase the expression level of inflammatory factors and apoptosis factors;At the same time,down-regulating the expression of apoptosis-inhibiting factors increased the apoptosis of the body in this way;In terms of autophagy,autophagy can be increased by increasing the expression of pro-autophagy factors and down-regulating the anti-autophagy factors.This experiment explored the effect of ammonia gas on the testis of mice to provide basic data for studying the effect of environment on mammalian reproductive function.