Establishment of a mouse model of acute systemic cold injury induced by hypothermia / 中华急诊医学杂志

ABSTRACT

Objective:To establish an animal model of acute systemic cold injury in mice.Methods:There were 98 C57BL/6 mice, half male and half female, with body weight of 22-27 g and age of 10 weeks. The mice were randomly divided into 7 groups ( n=14) according to the changes of anal temperature in cold environment, namely, group A (38.5 ± 1) ℃, group B (35 ± 1) ℃, group C (30 ± 1) ℃, group D (25 ± 1) ℃, group E (20 ± 1) ℃, group F (15 ± 1) ℃, and group G (10 ± 1) ℃, among which, group A was the blank control group, and the rest groups were the experimental group. The mice in the blank control group were placed in the normal environment (20 ± 5) ℃, and the mice in the experimental group were placed in the low temperature artificial climate box at - 20℃. The anal temperature of the mice was measured intermittently (as the core temperature), and the time required for the core temperature of the mice to drop to groups B, C, D, E, F and G was recorded. The righting reflex was used to evaluate the consciousness state, the action ability and the general state of each organ of mice were observed, and the blood routine and HE staining of each organ were detected. Results:The lower the core temperature of the experimental group, the longer the time required. The consciousness state, action ability, general state of organs, blood routine, and HE staining of organs in groups B, C, and D were basically the same as those in group A, and there was no acute systemic cold injury. Therefore, the blood routine, general observation of organs, and HE staining of organs in groups B, C, and D were no longer displayed compared with those in group A. Compared with group A, mice in group E began to suffer from disturbance of consciousness and action ability. With the decrease of core body temperature, the damage was aggravated, and mice in group G died. Compared with group A, the indices of blood routine test (WBC, RBC, HGB, PLT) of mice in group E began to decrease, and the univariate variance calculation showed that only WBC changes had statistical significance ( P<0.05). Compared with groups A and E, the indices of blood routine test (WBC, RBC, HGB, PLT) of mice in group F were further reduced, and the changes of each index in univariate variance calculation were statistically significant ( P<0.05). The general observation results showed that compared with group A, the lung, liver and spleen surfaces of mice in group E began to darken, and compared with groups A and E, the lung, liver, spleen, kidney and heart of mice in group F were further deepened and darkened, with irregular edges. HE staining results of various organs showed that compared with group A, the mice in group E began to have partial alveolar structure destruction and a small amount of inflammatory cell infiltration, the central vein of the liver was slightly congested, and the red and white pulp of the spleen were indistinct. Compared with groups A and E, the pathological structure damage of the lung, liver, spleen, kidney, heart and brain tissues of the mice in group F was further aggravated. Conclusions:Detection of consciousness state, action ability, general state of organs, blood routine and HE staining indices of organs in mice under low temperature can simulate the progress of clinical acute cold injury, and the animal model of acute systemic cold injury was successfully prepared.