Effects Of Extreme Climate Change On Lung Immune Function In Rats Based On The Theory Of "Heaven And Man 's Correspondence"

The theory of "Correspondence between man and nature" from Huangdi Neijing is an important part of the theoretical system of traditional Chinese medicine. And it has been guiding physiology, pathology, diagnosis, treatment and health preservation for more than two thousand years. It is also the world outlook and methodology of ancient Chinese people. Suilulun of Lingshu says:"Man and nature are interlinked", which highly summarizes the relationship between man and nature as both opposite and united. And with the rising of time, geographical and meteorological medicine, the interpretation of this theory become more and more comprehensive. It also contains a wealth of meteorological medical thoughts. For instance, " Many diseases are due to wind, cold, damp and dry" in Zhizhenyaodalun of Suwen indicates that diseases are related with wind, cold, heat, dryness, fire and others meteorological factors. Siqitiaoshendalun of Suwen also emphasizes that abnormal climate will not only cause diseases but also lead to the death of all living creatures. Extreme climate are abnormal, sudden and disastrous natural phenomena, whose frequent occurrence in recent years and impact on human physiology and pathology have drawn attention from scholars. Thus it is significant to reduce the damage of unavoidable extreme climate to the body through exploring the effects of extreme climate on human immune function.1 ObjectiveArtificial simulation system was used to explore and reveal the mechanism of lung immune function in rats under extreme climate conditions. And to provide new ideas and methods for the theory of "correspondence between man and nature" and to offer scientific data for the preventing diseases (especially respiratory infection and infectious diseases).2 Methods2.1 Experimental methods2.1.1 Experimental animals:One hundred Wistar male rats, weighted 120±20g, were bought from Beijing Weitong Lihua animal study center one week before experiment. They were randomly divided into natural control group and 6 groups of extreme climate with eight rats in natural control group and fifteen rats in each extreme climate group. Rats in the natural control group were put in the laboratory animal room with temperature of 25 degrees Celsius, humidity of about 50% and natural light. While temperature and humidity in extreme climate groups were manually controlled. All rats had free access to water and feed. Then, tissue sampling were taken at both 4h and 8h for the abruptly soared temperature group and abruptly dropped temperature group and at both 24h and 72h for the other extreme climate groups.2.1.2 Test methods:①INF-γ、IL-6 and sIgA in bronchoalveolar lavage fluid were detected by ELISA. ②MT and IL-10 in the rat lung were also detected also by ELISA.2.1.3 Analysis method:All the data were showed by mean±standard error and the difference of group were tested by SPSS20.0. Extreme climate groups were compared using single factor analysis of variance,.P<0.05 meaning obvious difference.3 Results3.1 INF-y、IL-6 and sIgA in bronchoalveolar lavage fluid showed the same variation: ①There was no significant difference (P>0.05) under conditions with sudden soared or dropped temperature.②Levels of the above three indices reduced under continuous high temperature condition and raided under normal temperature and high humidity condition, both changed with extremely significant difference (P<0.01).③These indices also reduced at 24h of continuous low condition and increased at 24h of high temperature and high humidity condition, both of which were significantly different (P<0.05).Thus, continuous high temperature condition and normal temperature and high humidity condition had the most significant effect on slgA, IL-6 and INF-y. The second influential states were high temperature and high humidity condition and the continuous low temperature condition, followed by abruptly soared and dropped temperature conditions.3.2 IL-10 and MT in rats lung tissue showed same changes:①IL-10 and MT lowered under the abruptly dropped temperature condition and significantly lowered under continuous low temperature condition (P<0.01). ②These two indices also decreased under abruptly soared temperature condition and high temperature and high humidity condition. And among them there were very significant difference (P<0.01) at 4h of the abruptly soared temperature condition and 72h of high temperature and high humidity condition.③At 24h of normal temperature and high humidity condition, IL-10 and MT also reduced significantly (P<0.05). ④Under continuous high temperature condition, IL-10 and MT raised but there was no significant difference (P>0.05).Therefore, the continuous low temperature condition and abruptly dropped temperature condition had the most significant influence on IL-10 and MT. And the second most influential states were abruptly soared temperature condition and high temperature and high humidity condition. This was followed by normal temperature and high humidity condition, with continuous high temperature condition being the least.3.3 The thymus and the spleen index:No obvious law showed in the thymus and the spleen index. As for the thymus index, it significantly increased (P<0.01) at both 8h of the abruptly dropped temperature condition and 24h of continuous low temperature condition. However, it reduced under high temperature and high humidity condition, but the difference was not significant(P>0.05). Thus, it indicated that sudden temperature drop and continuous low temperature had significant influence on rats thymus index, while the effect of other extreme climates was not significant. With regards to the spleen index, it reduced significantly (P<0.01) under the continuous high temperature and high temperature and high humidity conditions; And it raised under continuous low temperature condition with a significant difference (P<0.05) at 72h; Besides, it lowered under the normal temperature and high humidity condition and the difference at 72h was also significant (P<0.01).Therefore, the effects of continuous high temperature and high temperature and high humidity conditions on the spleen index was the most significant. Continuous low temperature and the normal temperature and high humidity conditions could also affect the spleen index. And the abruptly soared and dropped conditions were the least influential. As a result, the spleen index was significantly influenced by both high temperature and high humidity. Comparatively, it was low temperature that affected the thymus index significantly. 4 Conclusions4 ConclusionsThe changes of extreme climate have different degrees of impact on the immune function of rats lung, and different intervention factors can cause different immune factors in rats lung to response.