Construction method of desert dry and hot environment labor type heat stroke animal model

Abstract

The invention relates to the technical field of animal models, in particular to a desert dry and hot environment labor type heat stroke animal model construction method which comprises the following steps: step 1, performing running training on rats for at least 5 days in advance; and step 2, putting the rat at the temperature of 38-44 DEG C and the relative air humidity of 5-25%, and continuously running for at least 20 minutes to obtain the desert dry and hot environment labor type heat stroke animal model. According to the method, a typical labor-type heat stroke rat model in the desert dry and hot environment can be formed, the survival rate in one hour is high, the model forming time is short, and an animal model which is high in success rate, stable and standard can be provided for the labor-type heat stroke in the desert dry and hot environment.

Description

Technical Field

[0001] The present invention relates to the technical field of animal models, and in particular to a method for constructing an animal model of exertional heatstroke in a dry and hot desert environment. Background Art

[0002] Much of Xinjiang's geological exploration and natural resource development work is carried out in the dry, hot desert environment. The high intensity of physical activity and the unique high temperature and low humidity of the desert's dry, hot environment lead to an imbalance between heat production and heat dissipation, making heat stroke more likely. In severe cases, this can lead to exertional heat stroke. The main manifestations of exertional heat stroke include impaired consciousness, rhabdomyolysis, disseminated intravascular coagulation, and acute multiple organ dysfunction syndrome induced by high-intensity physical activity. Currently, there is no stable and effective animal model for exertional heat stroke research in the dry, hot desert environment. Summary of the Invention

[0003] The present invention can provide a stable and standardized animal model with a high success rate for the development of early warning of the occurrence and development of exertional heat stroke in dry and hot environments, formulation of treatment plans, standardization of treatment processes, disease occurrence and development mechanisms, and development of specific drugs.

[0004] The present invention solves the technical problem by adopting the following technical solutions: In a first aspect, the present invention provides a method for constructing an animal model of exertional heat stroke in a dry and hot desert environment, comprising the following steps: Step 1: Perform running training on rats at least 5 days in advance; Step 2: Place the rats in an environment with a temperature of 38-40°C and a relative humidity of 5-20%, and run continuously for at least 20 minutes to establish an animal model of exertional heat stroke in a dry, hot desert environment.

[0005] In one or more embodiments of the present invention, the running environment in step 1 is a temperature of 18-25° C. and a relative humidity of 35-50%.

[0006] In one or more embodiments of the present invention, the running environment in step 1 is a temperature of 20-24° C. and a relative humidity of 35-45%; The running environment in step 2 is a temperature of 41±1° C. and a relative humidity of 15±5%.

[0007] In one or more embodiments of the present invention, the running training cycle in step 1 is 5-10 days, the running training speed on the first day is 8-10 m / min, and the running training speed on the last day is 13-17 m / min. The running speed is at least 10 minutes per day during the running training cycle.

[0008] In one or more embodiments of the present invention, the running training cycle in step 1 is 6-8 days, the running training speed on the first day is 8-10 m / min, the daily speed increases by 0.5-1.5 m / min from the second to the fifth day, the running training speed on the 6th to the 8th day is 14-16 m / min, and the running speed is constant for 12-18 minutes every day during the running training cycle.

[0009] In one or more embodiments of the present invention, the running training cycle in step 1 is 7 days, the running training speed on the first day is 10 m / min, the speed increases by 1 m / min every day from the second to the fifth day, and the running training speed on the 6th to 7th day is 15 m / min. The running training cycle is carried out at a constant speed for 15 minutes every day.

[0010] In one or more embodiments of the present invention, the speed of the running training in step 2 is 12-18 m / min.

[0011] In one or more embodiments of the present invention, the speed of the running training in step 2 is 14-16 m / min.

[0012] The present invention has the following beneficial effects: the present invention can create a typical exertional heat stroke rat model in a dry and hot desert environment, with a high 1-hour survival rate and a short model formation time, and can provide a high success rate and stable and standardized animal model for exertional heat stroke in a dry and hot desert environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the animal model of exertional heat stroke in a dry and hot desert environment of Example 1.

[0014] Figure 2 This is a graph of the rectal core temperature of rats in an animal model of exertional heat stroke in a dry and hot desert environment from the beginning to the success of modeling.

[0015] Figure 3 This is a pathological diagram of myocardial damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0016] Figure 4 This is a pathological diagram of liver damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0017] Figure 5 This is a pathological image of lung tissue damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0018] Figure 6 This is a pathological diagram of renal tissue damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0019] Figure 7 This is a pathological diagram of brain tissue damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0020] Figure 8 This is a pathological diagram of skeletal muscle damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0021] Figure 9 This is a pathological diagram of intestinal damage in an animal model of exertional heat stroke in a dry and hot desert environment.

[0022] Unless stated otherwise, the terms used in the specification and claims have the following meanings.

[0023] As used herein, the term "prevention" refers to preventing the occurrence of a disease and / or preventing the recurrence of a disease. DETAILED DESCRIPTION

[0024] While the present invention specification describes specific embodiments in detail, those skilled in the art should recognize that the following embodiments are illustrative and are not to be construed as limiting the present invention. Those skilled in the art will appreciate that improvements and modifications to the present invention, without departing from the principles of the present invention, will be made, and that the resulting technical solutions will fall within the scope of the claims. The following examples illustrate the beneficial effects of the present invention.

[0025] Example 1

[0026] Experimental construction of an animal model of exertional heatstroke in a dry and hot desert environment 1. Experimental Methods 1. Experimental Animals Twenty SPF-grade SD male rats weighing 250–280 g were purchased from the Experimental Animal Center of Xinjiang Medical University [SCXK (Xin) 2016-003]. The experiment was approved by the Animal Experiment Ethics and Welfare Committee of the General Hospital of Xinjiang Military Region.

[0027] 2. Experimental Environment The experimental group (EHS group) was placed in the Northwest Special Environmental Test Chamber at the Xinjiang Military Region General Hospital, with a temperature of 41±1°C and a relative humidity of 15±5%. The control group was placed in a temperature of 22±2°C and a relative humidity of 40±5%.

[0028] 3. Adaptive training One week before the experiment, all experimental rats were trained and adapted to the forced running system. Stimulating electrodes were set at the end of each runway, and the electrical stimulation was set to 1mAh to force the rats to run. The temperature was 22±2℃ and the relative humidity was 40±5%. On the first day, the rats ran for 15 minutes at an initial speed of 10m / min. On the second day, the rats were forced to run at a speed of 12m / min for 15 minutes. Subsequently, the exercise time was 15 minutes per day, and the speed increased by 1m / min. On the sixth and seventh days, the speed was 15m / min and remained unchanged. During this period, all rats had free access to water and food.

[0029] 4. Establishment of a rat model of exertional heat stroke in a dry desert environment Rats were subjected to continuous running at a speed of 15 m / min in a hot, dry desert environment (temperature: 41 ± 1°C, relative humidity: 15 ± 5%). A core body temperature reaching 42.5°C was considered a successful rat model of exertional heat stroke (EHS). By continuously recording changes in core body temperature, the classification of post-exercise heat stroke was refined and the timing of modeling for different degrees of exertional heat stroke was determined.

[0030] 5. Metrics Collection The rats' core body temperature was continuously recorded, and changes in their mental and motor states were observed. After successful modeling, the liver, lungs, heart, brain, kidneys, small intestine, and skeletal muscle were immediately removed and fixed with 10% formaldehyde solution and then stained with HE.

[0031] 2. Experimental Results 1. Body temperature changes The rectal core temperature of the rats was monitored every 5 minutes using an electronic thermometer. Figure 2 This is a graph of the rectal core temperature of rats in the animal model of exertional heat stroke in a dry and hot desert environment from the beginning of modeling to the success of modeling. It can be seen from the graph that the average core temperature at 10 minutes is 39.54°C, the average core temperature at 20 minutes is 40.65°C, the average core temperature at 30 minutes is 41.6°C, and the average core temperature at 40 minutes is 42.51°C.

[0032] When exercising in a dry heat environment, a core body temperature of 39.5°C to 40.5°C in SD rats is considered mild heatstroke, 40.5°C to 41.5°C is moderate heatstroke, 41.5°C or higher is severe heatstroke, and 42.5°C or higher is exertional heatstroke. The average duration of exercise in a dry heat environment (temperature: 41±1°C, relative humidity: 15±5%, speed: 15 m / min) to establish different degrees of exertional heatstroke in rats is: mild heatstroke (39.5°C to 40.5°C) is 10 minutes, moderate heatstroke (40.5°C to 41.5°C) is 20 minutes, severe heatstroke (above 41.5°C) is 30 minutes, and exertional heatstroke (above 42.5°C) is 40 minutes.

[0033] The experimental rats adapted well to exercise in the dry heat environment, completing the pre-set exercise time and reaching the corresponding core body temperature. During exercise, body temperature varied significantly over time, and exertional heat stroke occurred in the experimental rats for approximately 40 minutes.

[0034] 2. Pathological damage of various organs 2.1 Cardiac pathological damage Figure 3 This image shows myocardial pathology in an animal model of exertional heat stroke in a dry, hot desert environment. The control group showed intact, neatly arranged cardiomyocytes with no apparent inflammatory cell infiltration. The dry, hot, exertional heat stroke group showed mild swelling of the myocardium, with large areas of eosinophilia, scattered cells with condensed nuclei, and extensive inflammatory cell infiltration.

[0035] 2.2 Liver pathological damage Figure 4 This image shows liver pathology in an animal model of exertional heat stroke in a dry, hot desert environment. No significant abnormalities were observed in the control group, while the EHS group showed unclear lobular structure, hepatocyte edema and granular degeneration, numerous hepatocytes with eosinophilic degeneration and nuclear condensation, and punctate necrosis.

[0036] 2.3 Pathological damage of lung tissue Figure 5 This image shows lung tissue pathology in an animal model of exertional heatstroke in a dry, hot desert environment. Microscopic observation of the EHS group revealed edema of the interstitial venous walls of the lung tissue, white thrombi in small paratracheal vessels, swelling of some endothelial cells with condensed nuclei, and sloughing into the vascular lumen. Surrounding the thrombus-containing vessels were partially shrunken alveoli with widened alveolar septa. Some lung tissue showed consolidation, condensed nuclei in alveolar epithelial cells, and occasional intra-alveolar neutrophil infiltration. Lymph nodules were observed near the trachea.

[0037] 2.4 Pathological damage of renal tissue Figure 6 These images show renal tissue pathology in an animal model of exertional heatstroke in a dry, hot desert environment. Microscopic examination of the EHS group revealed dilated and congested glomeruli in some renal cortexes, narrowed cystic cavities, and unclear lumens in the surrounding proximal and distal convoluted tubules. Some interstitial vessels were also congested and dilated. In the medulla, edema, condensed nuclei, and occasional epithelial cell detachment were observed in some collecting duct epithelial cells, and congestion of the collecting duct interstitial space was observed.

[0038] 2.5 Pathological damage of brain tissue Figure 7This image shows pathological brain tissue damage in an animal model of exertional heatstroke in a dry, hot desert environment. High-power microscopy reveals a small number of edematous cells in the cerebral cortex of the EHS group, some with condensed nuclei. Infiltration of lymphocytes and neutrophils is also evident. Capillaries are partially dilated and congested, with occasional thrombosis.

[0039] 2.6 Skeletal muscle pathological damage Figure 8 This image shows skeletal muscle pathology in an animal model of exertional heatstroke in a dry, hot desert environment. Compared to the control group, the EHS group showed disorganized muscle fiber structure, a significant increase in white muscle fibers, a small amount of inflammatory cell infiltration in the interstitium, and granular changes in some skeletal muscle fibers.

[0040] 2.7 Intestinal pathological damage Figure 9 Figure 2 shows intestinal pathological damage in an animal model of exertional heatstroke in a dry, hot desert environment. Compared to the control group, the EHS group showed ileal mucosal epithelial desquamation, exposed lamina propria, congestion of lamina propria capillaries, massive lymphocyte infiltration, hyperplasia of interglandular connective tissue in the small intestine, and ulceration of intervillus patches. Submucosal blood vessels were dilated, and the distance between the connective tissue and the basal layer of the mucosa was increased.

[0041] 3. Conclusion 1. The present invention successfully established a rat model of exertional heat stroke in a dry hot environment, which met the diagnostic criteria of exertional heat stroke: 1. body temperature ≥ 42.5°C; 2. presence of neuropsychiatric symptoms; 3. presence of multiple organ dysfunction.

[0042] 2. The average time required to establish different degrees of dry heat exertional heat stroke rat models under dry heat environment exercise conditions (temperature: 41±1°C, relative humidity: 15±5%, speed 15m / min) is: mild heat stroke (39.5°C-40.5°C) is 10 minutes, moderate heat stroke (40.5°C-41.5°C) is 20 minutes, severe heat stroke (above 41.5°C) is 30 minutes, and exertional heat stroke (above 42.5°C) is 40 minutes.

[0043] 3. This invention can create a typical exertional heat stroke rat model in a dry and hot desert environment, with a high one-hour survival rate and a short model formation time. It can provide a stable and standardized animal model with a high success rate for exertional heat stroke in a dry and hot desert environment.

[0044] The specification of the present invention describes the specific implementation scheme in detail. Those skilled in the art should recognize that the above implementation scheme is exemplary and cannot be understood as limiting the present invention. For those skilled in the art, without departing from the principles of the present invention, by making several improvements and modifications to the present invention, the technical solutions obtained by these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for constructing an animal model of exertional heat stroke in a dry and hot desert environment, characterized in that: The steps include: Step 1: Perform running training on rats at least 5 days in advance; Step 2: Place the rats in an environment with a temperature of 38-44°C and a relative humidity of 5-25%, and run continuously for at least 20 minutes to obtain an animal model of exertional heat stroke in a dry and hot desert environment.

2. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 1, characterized in that: The running environment in step 1 is a temperature of 18-25° C. and a relative humidity of 35-50%.

3. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 1, characterized in that: The running environment in step 1 is a temperature of 20-24°C and a relative humidity of 35-45%; The running environment in step 2 is a temperature of 41±1° C. and a relative humidity of 15±5%.

4. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 1, characterized in that: The running training cycle in step 1 is 5-10 days, the running training speed on the first day is 8-10 m / min, and the running training speed on the last day is 13-17 m / min. The running speed is at least 10 minutes per day during the running training cycle.

5. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 4, characterized in that: The running training cycle in step 1 is 6-8 days, the running training speed on the first day is 8-10 m / min, the daily speed increases by 0.5-1.5 m / min from the second to the fifth day, the running training speed on the 6th to the 8th day is 14-16 m / min, and the running speed is constant for 12-18 minutes every day during the running training cycle.

6. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 5, characterized in that: The running training cycle in step 1 is 7 days, the running training speed on the first day is 10m / min, the speed increases by 1m / min every day from the second to the fifth day, the running training speed on the 6th to the 7th day is 15m / min, and the running speed is constant for 15 minutes every day during the running training cycle.

7. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 1, characterized in that: The speed of the running training in step 2 is 12-18 m / min.

8. The method for constructing an animal model of exertional heat stroke in a dry and hot desert environment according to claim 7, characterized in that: The speed of the running training in step 2 is 14-16 m / min.

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