RESUMO
Objective To observe the effects of seawater immersion at different temperatures on survival time and mortality and physiological state of non-anesthetized rats.Methods Totally 100 SD male rats(The abdominal cavity was implanted with a temperature sensor in advance)were randomly divided into five groups which were immersed in 20 ℃,17 ℃,15 ℃,13 ℃ and 10 ℃ seawater,respectively.Each group contains 20 rats.The changes of respiration,heart rate and muscle fibrillation within 2 hours were observed and the survival time and mortality of each group were counted in 24 hours.The decrease trend of intraperitoneal temperature in rats was analyzed retrospectively within 2 hours.Results Soaking for 10 minutes,the respiratory and heart rate of each group were significantly increased,but there was no significant difference among groups(P>0.05).The respiratory and heart rate decreased rapidly between 10 and 40 minutes,and the decline was slower relatively between 40 and 80 minutes.Soaking for 80 minutes,the respiration rate of rats among groups had significant difference(P0.05),hereafter the muscle fibrillation was maintained at a certain level.The mean survival time of 20 ℃ group,17 ℃ group,15 ℃ group,13 ℃ group and 10 ℃ group in 24 hours were(23.6±1.23)hours,(15.0±4.16)hours,(7.7±3.21)hours,(2.4±0.91)hours and (1.1±0.39)hours,respectively,and the survival curve of each group was statistically significant(P<0.05).The intraperitoneal temperature of rats showed a decline in the cliff,the lower the water temperature,the faster the descending.Soaking for 40 minutes,the difference of intraperitoneal temperature of each group was statistically significant(P<0.05).Conclusion The effects of seawater immersion at different temperatures on the physiological state and survival time and mortality of rats are significantly different.With the decrease of water temperature,the physiological state changes more obviously,the survival time is shorter and the mortality rate is higher.