Characteristics of liver injury and its correlation with interleukin - 1 beta and intercellular adhesion molecule-1 in rats with different exposure time in dry-heat environment

Xia Liang; Liu Jiang- wei; Shen Cai- fu; Zhao Yin- hui; Li Jia- jia; Ma Na; Shi Wen- hui

doi:10.3969/j.issn.1002-1949.2017.10.020

Abstract：Objective To investigate the characteristics of liver injury and its correlation with interleukin -1 beta (IL-1β) and intercellular adhesion molecule-1 (ICAM-1) in rats with different exposure time in dry-heat environment. Methods Forty male SD rats were randomly divided into two groups:normal environment control group and dry-heat environment exposure group, and the dry-heat environment exposure group was divided into three groups of 50 min, 100 min, 150 min according to different exposure time;each group had 10 rats. The dry-heat environment exposure groups were placed in the Simulated Climate Cabin for Special Environment of Northwest of China with the conditions of (41 ± 0. 5)°C temperature,(10 ± 1)% relative humidity for heat exposure. In the time point of 0 min, 50 min, 100 min, and 150 min, the rats of corresponding groups ( normal environment control group was seemed as 0 min group of heat exposure) were measured core temperature ( Tc) and then anesthetized for collecting blood and liver samples for following detection including alanine aminotransferase ( ALT ) , IL-1β, ICAM-1. Histology changes of liver were observed by light microscope and pathological scores were measured. Results The indexes showed different degrees of increase with the extension of exposure time in dry - heat environment. The liver pathology showed edema of liver cells, liver sinusoidal dilatation and inflammatory cells infiltration, central venous congestion and blotting, and the extent increased gradually. Compared with the previous time point, the differences of indexes in the time point of 50 min, 100 min, 150 min were significant (P<0. 05) except the difference of ALT between 50 min and 0 min (P>0. 05). In the time point of 100 min, the temperature of rats reached to 41. 8 ℃and caught heatstroke. Pathological scores, IL-1β and ICAM-1 increased obviously in the time point of 100 min, while ALT increased obviously in the time point of 150 min. Correlation analysis showed that pathological score was closely related to IL-1β(r=0. 924, P<0. 05) and ICAM-1 (r=0. 975, P<0.05). IL -1β and ICAM -1 were closely related (r =0.943, P <0. 05). Conclusion Liver pathological injury occurs in the early stage of heatstroke in dry-heat environment, and the extent of liver injury is parallel to the expression of IL -1β and ICAM -1. Endotoxin induces inflammatory reaction in the hepatic sinusoid and then damages the endothelial cells, resulting in microcirculatory obstruction, which might be one of the causes of liver injury. Moreover, IL-1βand ICAM-1 might be the early indicator of liver injury in heatstroke in dry -heat environment while serum ALT could not reflect the early liver injury.