摘要
目的为探讨环境因素对飞行的影响，用高温、噪声及两者结合观察对大鼠心脏扩张素（CDD）的影响。方法80只Wistar大鼠随机分为四组：即高温组（40℃，湿度82％）、噪声组（115dB）、两组条件相加的复合组和对照组。用特异性放射免疫法测定CDD含量。结果对照组、高温组、噪声组及复合组血浆CDD含量分别为73．32±8.29、111．72±12．97、328．65±67．27及79.25±11.14Pmol／L。与对照组比较，噪声组及高温组均有明显增高（P＜0．05），复合组无显著性差异（P＞0．05）。结论血浆CDD增高是机体增加心排出量的一种代偿反应。在复合因素的作用下，大鼠血浆CDD含量未增加，说明它们处于代偿低下状态。
Objective Plasma cardiodilatin(CDD) levels were determined in rats following exposure to high temperature, noise and combination of them. Methods Eighty Wistar rats were randomly divided into 4 groups (20 each):control group (gr 1),high temperature group (gr 2),noise group(gr 3),and combined group (gr 4). In gr 2 rats were exposed to 40℃ atmospheric temperature, 82 % relative humidity, gr 3 exposed to 115 dB(A) noise, and gr 4 to both for 1 h. Arterial blood samples weretaken immediately after exposure and CDD levels were determined with radioitnmunoassay. Results Itwas found that plasma CDD level in gr 1 - 4 were 73- 32;8- 29, 111. 72 ± 12. 97, 328. 65 ± 67. 27 and79. 25± 11. 14 pmol/L respectively. The plasma CDD level of noise group was significantly increased,compared with those of other three groups (P＜0.01). The CDD level of gr 2 was also significantlyhigher than gr 1 (P＜0.01), CDD level of gr 4 had no significant change, compared with the CDD levelof gr 1 (P＞0.05). Conclusion Increase of plasma CDD is considered as a compensatory response toenhance cardiac function. Unchanged CDD level in gr 4 may be due to lowering of compensative abilityunder the combined influence of high temperature and strong noise.
