| Research Objectives Through observing the weight of rats ahout the high-temperature environment for three months(short-term) andhigh-temperature environment for six months(long-term) about and statisticing analysis of spleen,liver,lung coefficient and on the levels of serum IL-1(IL-1),IL-2(IL-2)and lysozyme to investigate the effect on immune toxicity of rats and offsprings.Research Methods ① Choose Healthy adult SD(Sprangue Dawley) 80 rats,weight 200±20g.According to the principle of randomization into four groups:the medium-term exposure group(n=20,male and female);medium-term control group(n=20,male and female);long-term exposure temperature group(n=20,male and female);long-term control group(n=20,male and female).②Feed rats one week at room temperature(16~20℃).Then continue to breed medium and long-term control group in the natural environment at room temperature.put the medium-term,long-term exposure group into artificial climate chamber temperature of(38 ± 1) ℃;relative humidity(55 ± 5)%),daily 12:00-14:00conducted 2h exposure to hot environment. Observe and record changes in body weight of rats in each group.After 12 weeks on the mid-term high temperature exposure group,the control group of rats mid anatomy and physiology of immune index detection.After 24 weeks of group long-term exposure,the anatomy and physiology of the immune parameters were measured long-term control group of rats.③At the end of 16 weeks,long-term exposure group,long-term control group within each group were mated male and female rats,after a week on the femalesample under a microscope to see if the pregnancy vagina,were reared to ensure offspring after conception to birth to baby.After the rat lactation,according to the randomization principle in each group were randomly selected male and female offspring 10 each.The first generation rats were divided into sub-generation high-temperature exposure group(n=20,male and female);sub-generation control group(n=20,male and female),followed by the anatomy and physiology of immune parameters were measured.Results ①hot mid-term exposure group compared with the control group decreased the amount of weight gain. There is a significant difference, p<0.05;after the mid-term exposure to hot environment, coefficient of spleen and liver is elevated(p<0.01)compared to control group.There is no coefficient significant difference compared with the control group(p>0.05)in lung coefficient;the mid-high temperature of rats exposed to hot environment group compared with the control group,serum IL-1 levels were significantly higher(p<0.01),significantly reduced in IL-2 content(p <0.05),lysozyme activity is increased significantly(p<0.05)after long-term exposure to hot environment.②There is greater growth in body weight of rats hot environment exposure group than the control group,the difference was statistically significant(p<0.05);high temperature coefficient rat spleen decreased compared with the control group,lung coefficient than the control group,a statistically significance(p<0.05),no significantly difference in liver coefficient;hot environment exposure group compared with the control group,the serum IL-1,IL-2content and lysozyme activity were no significant difference(p<0.05).③After long-term exposure in hot environment,the amount of weight in rats is higher than the growth in the amount of weight after the mid-exposed rats,the difference was statistically significant(p<0.01);long-term exposure to high temperatureand high-temperature exposure group compared with the mid-term group,spleen,liver,lung coefficients decrease was statistically significant(p<0.05);long-term group exposure to high temperature with the mid-term group,IL-1 decreased and there is a significant difference(p<0.05);IL-2 content and lysozyme activity were increased,the difference was statistically significant(p<0.01).④After long-term exposure to hot enviroment, the amount of weight grew less than in the control group of rats,the difference was statistically significant(p<0.05);long-term set of sub-generation high-temperature coefficient spleen decreased compared with the control group,there was statistically significant(p<0.05);no liver,lung coefficient compared with the control group with a significant difference;long-term exposure to high temperature and high-temperature group first generation of rats compared with the control group,serum IL-1 was reduced,the difference was statistically significant(p<0.05);IL-2 was reduced,there was a significant difference(p<0.05);lysozyme activity decreased with statistical significance(p<0.05).Research conclusion ① Mid-exposure group of hot environment rats weight is lower than the control group;spleen,liver index is increased with the control group significantly;serum levels of IL-1 is higher than the control group,IL-2 level is lower than the control group,lysozyme levels were significantly increased.②long-term exposure to high temperatures increase the amount of weight in rats with the control group;coefficient of spleen increased and lung coefficient is decreased with the control group;serum levels of IL-1and IL-2,ysozyme activity were not significantly changed.③Weight of long-term exposure to high temperatures is increased higher than the mid-term group;spleen,liver,lung coefficient in long-term exposure group is decreasedthan in the mid-exposed group;the levels of IL-1 and IL-2 are increased in long-term exposure to high temperatures group with the mid-exposed group,Lysozyme activity was decreased. ④ the weight of sub-groups rats in long-term exposure group is decreased;the coefficient of spleen of long-term exposure sub-group is lower than the control group;the levels of IL-1,IL-2 and lysozyme activity of long-term exposure sub-group are decreased.In summary,the present study in rats by measuring the coefficient of the organ and detect serum cytokines Tip:The serum levels of IL-1 and lysozyme activitymid-term exposure to hot environment are increased,the serum levels of IL-2 are decreased;there is no significance in long-term exposure to high temperatures on serum IL-1,IL-2 and lysozyme activity;long-term exposure to high temperatures can reduce offspring in rats serum IL-1,IL-2 and lysozyme levels.The immune function of rats is destroyed by the hot environment. |
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