Fig. 1 HE staining results of DSS acute colitis section

2.Zebrafish modeling

1) Zebrafish embryos were cultured in E3 embryo medium containing methyl blue at 28.5 ℃ until 1 dpf;

2) 0.5% DSS drinking water was configured with E3 medium and then filtered through a 0.22 μm filter membrane;

3) Zebrafish were treated with 0.5% DSS from 3 dpf to 6 dpf.

4) Experimental results: all 0.5% DSS drug treatments resulted in darkening of zebrafish liver color and inflammatory stress.

Fig. 2 DSS causes an inflammatory response in the zebrafish liver

3.Pig molding

1) Four to five day old Yorkshire piglets, experimental group: perfused with DSS, control group: perfused with saline

2) Daily intake of 1.25g DSS/kg per piglet, infused for 5 days

3) Experimental results: After instillation of DSS, the plasma D-mannitol uptake rate of the experimental group was significantly higher than that of the control group, indicating that the piglets showed symptoms of enteritis visible to the naked eye.

Fig. 3 DSS induced higher concentration of D-mannitol in piglets than in controls

4.Drosophila modeling

1) 5- to 10-day-old female Drosophila were placed in an empty vial containing 2.5 × 2.5 × 1-cm vials in culture with 3.75-cm chromatography paper (Fisher) feed media moistened with 5% sucrose solution;

2) Feeding media containing different components were prepared separately with 5% sucrose solution, and the categories included 3% DSS each and 25 μg/ml bleomycin;

3) Drosophila were placed in flasks containing chromatography paper and incubated at 29°C for three days, during which time the surviving Drosophila were transferred daily to empty flasks containing fresh medium;

4) Experimental results: DSS has a lethal function and DSS induces proliferation of ISC precursor cells.

Fig. 4 DSS induces proliferation of ISC precursor cells in Drosophila

IV. How to evaluate the success of modeling?

1.DiseaseActivity Index (DAI score)

Three aspects were assessed and scored: weight, fecal consistency, and fecal occult blood, and the DAI score was the sum of the three indicators.

Table 2 DAI scoring rules

score (of student's work)	Percentage of weight loss	fecal viscosity	fecal occult blood
0	0	normalcy	negatives
1	1-5%	soft stool	pale blue
2	5-10%	mucus-like stool	blue (color)
3	10-20%	loose, liquidy stool	Deep Blue
4	＞20%	/	Bloody stool to the naked eye

 

2.Scoring of histologic changes

Histologic changes were scored as the sum of the above, and lymph node formation was not scored in the acute colitis model. The standard method for histologic analysis was HE staining (Cat. NO: 60524ES60).

Table 3 Histological change scores

score (of stude nt's work )	Ulcers (number)	Epithelial cell changes	inflammatory infiltrate	Lymph nodes (nos.)
0	0	Normal	None	None
1	1	Absence of cupped cells	Pericryptal infiltration	1
2	2	Large deletion of cupped cells	Infiltration of the muscular layer of the mucosa	2
3	3	crypt fossa	Generalized infiltration of the muscular layer of the mucosa with thickening of the mucosa	3
4	＞3	Large absence or polypoid regeneration of the crypt fossa	submucosal infiltration	＞3

 

3.Colon length

Colonic length shortening was detectable on day 8 in the acute colitis model; it was more pronounced in the chronic colitis model.

4.Summary

DSS UC animal model construction should be preceded by pre-tests to feel the modeling conditions, and it is recommended that pre-tests be conducted with 8-10 samples in each group, and a control group should be set up. Usually, the appearance of weight loss, loose stools, diarrhea, bloody stools or fecal occult blood, ulceration can be regarded as the DSS drug is effective and the modeling is successful.

VI.Yeasen DSS Modeling Case Study

Yeasen DSS (Cat. No: 60316ES, MW:36000~50000) is widely used in the construction of UC models. Yeasen

 DSS can successfully build UC models with results comparable to imported brands.

Objective: To compare the extent of change in body weight of mice affected by DSS-induced acute colitis from different manufacturers.

Mouse type: BALB/c mice ;

Modeling protocol: 2% DSS concentration, continuous free-flow drinking for 1 week.

Conclusion: The trend of body weight loss induced by Yeasen DSS in mice was consistent with that of the imported brand.

And we found that the acute colitis modeling time is mainly concentrated in about 7 days, the effect is very significant. The following table is the data feedback from some customers.

Table 4 Modeling different types of enterocolitis with DSS

Mould	Template	Molding Solutions	Molding results	Testimonials
acute colitis	BALB/c mice, female, 6-8 weeks, 25 g	3%-5% DSS for 7 days of continuous free-flowing consumption	Day5 presentation with shortened colon length, HE staining, and marked inflammation	Fast modeling speed and short time. Conforms to the characteristics of the acute colitis model
	C57BL/6 mice, male, 8 weeks, 20 g	3%-5% DSS by gavage, continuous administration	Day5 present, shortened colon length, weight loss, blood in stool, diarrhea	High modeling rate and short time. Consistent with acute colitis model characteristics
chronic  colitis	C57BL/6 mouse, male, 8 weeks, 22 g	1-2% DSS by gavage, continuous administration	Day40 present, shortened colon length, weight loss, blood in stool, diarrhea	High modeling rate. Consistent, with chronic colitis model characteristics
Colon cancer	C57BL/6 mouse, male, 8 weeks, 21 g	1%-2% DSS freely available for 5 days for 3 weeks	14 weeks Present, shortened colon length, weight loss, HE staining, inflammation evident	High modeling rate. Consistent with colon cancer model characteristics

 

Product Features:

1. Symptomsarehighly similar to those of human UC: it can be used to study the mechanism of colitis and pharmacodynamic studies.
2. Highmoldformation rate: free drinking DSS aqueous solution, simple and easy, 
3. canconstructa variety of colitis models: acute colitis, chronic colitis, can also be combined with AOM to construct colitis- associated cancer (CAC) model.
4. Itissuitable for the modeling of many kinds of animals: mice, rats, zebrafish, pigs, fruit flies and so
5. highsecurity:DSS can be degraded by the natural ecosystem, safe for the environment; 6, high purity: high purity (98%), sulfur content 17-19%;

VII. Frequently asked questions

Whether acute DSS colitis model or chronic DSS colitis model, the severity and success of enteritis is related to mouse species (different genetic backgrounds), DSS concentration, and dosing cycle.

Table 5 Frequently asked questions for DSS colitis modeling

Possible problems	Possible causes	Suggested solutions
High lethality in mice	DSS concentration too high	Reduced concentration of DSS administration
Mice with no or low signs of enteritis	DSS concentration too low	Elevated DSS dosing concentration; reduced cycle interval (10- 14 days)
In the same group of mice, the symptoms of enteritis varied greatly	Clogged cap	Check mouse drinking bottles daily

 

VIII.Product Ordering

Product name	Catalog number	Specification
Dextran Sulfate Sodium Salt (DSS) Dextran Sodium Sulfate for Colitis Modeling MW:36000~50000	60316ES25	25 g
Dextran Sulfate Sodium Salt (DSS) Dextran Sodium Sulfate for Colitis Modeling MW:36000~50000	60316ES60	100 g
Dextran Sulfate Sodium Salt (DSS) Dextran Sodium Sulfate for Colitis Modeling MW:36000~50000	60316ES76	500 g
Dextran Sulfate Sodium Salt (DSS) Dextran Sodium Sulfate for Colitis Modeling MW:36000~50000	60316ES80	1 kg
Hematoxylin and Eosin Staining Kit Hematoxylin Eosin (H&E) Staining Kit	60524ES60	2 x 100 mL

 

Modeling of acute pancreatitis in animals

Caerulein is a gastric regulatory molecule functionally and compositionally similar to cholecystokinin (CCK) that stimulates gastric, biliary and pancreatic secretion. Rainfrogin can be used to study signaling pathways mediated by NF-κB up-regulated proteins such as Intercellular Adhesion Molecule (ICAM-1), inflammation-related factors such as NADPH oxidase, and Janus kinase. And it has been successfully used in the establishment of acute pancreatitis (AP) models in rats, mice, dogs and Syrian hamsters.

Moulding Advantage:

1. easyoperation
2. lower cost
3. rapid prototyping
4. multiplemodesof drug delivery

Modeling Mechanisms:

1. Upregulationof intercellular adhesion molecule (ICAM-1) expression in pancreatic alveolar cells by stimulating intracellular NF-KB. Surface ICAM-1 in turn promotes neutrophil adhesion to alveolar cells thereby enhancing pancreatic inflammatory effects;
2. Inducespancreatitis by inducing dysregulation of digestive enzyme secretion and cytoplasmic vacuolization leading to death of alveolar cells and pancreatic edema;
3. Activation of inflammation-promoting factors.

Related Reagents

Yeasen provides decapeptide molecular form, purity ≥97% (HPLC) rain frogin; high molding efficiency, favorable price, spot supply.

Product name	Catalog number	Specification
Caerulein	60321ES03	1 mg
DMSO Dimethyl Sulfoxide (cell culture grade)	60313ES60	100 mL

Diabetes disease modeling

Streptozocin (STZ) is an antitumor antibiotic produced from a certain type of Streptomyces fungus, Aureobasidium pullulans, and can also be synthesized. It is often used in the treatment of pancreatic cancer. At the same time, STZ has a selective destructive effect on the pancreatic islet β-cells of certain species of animals, and can induce diabetes in many animals, generally using rats and mice to create animal models. It has been widely studied in anti-leukemia, DNA methylation, and anti-nephritis.

1.1 Preparation of animals

Try to use male animals, females contain hormones that affect modeling efficiency. Some studies have shown that female animals have poor modeling rates and may experience higher mortality rates than males, especially for type I.

Type I diabetes (Type I diabetes) can generally be selected according to the body weight, recommended 170-200g for rats and 17-22g for mice, and the modeling rate is relatively ideal when STZ is injected in fasting after 1~2 weeks of adaptive feeding.

For Type II diabetes, rats (e.g. SD/Wistar) are selected at 4-5 weeks of age, weighing 90-100g, and fed high-fat (high-sugar) diets for 4-6 weeks to reach a body weight of about 240-280g. For mice (e.g. C57/ICR/Kunming mice) are selected at 4-5 weeks of age, weighing 16-20g, and fed high-fat (high-sugar) diets for 4-6 weeks to reach a body weight of about 30-35g. For newly purchased animals or those changing feeding environments, they need to be fed on regular diets for one week before selecting the appropriate age/weight to switch to high-fat (high-sugar) feed. For mice (e.g. C57/ICR/Kunming mice), select 4-5 weeks old, weighing 16-20g, and fed high-fat (high sugar) diets for 4-6 weeks to reach a body weight of about 30-35g. For newly purchased animals or a change of feeding environment, it is necessary to adaptively feed the animals with normal diets for one week, and then select the appropriate weekly age/body weight animals and switch to high-fat, high-sugar diets. In terms of modeling success, SD is recommended for rats and C57 for mice.

1.2 Feeding before molding

Feeding before modeling, type I diabetes model is relatively fast, usually rats can start modeling after 2 weeks of adaptive feeding on normal feed; type II diabetes model: high-fat diet induction plus a small dose of STZ. high-fat (high-sugar) feed was fed before modeling, which induced insulin resistance.

1.3 Preparation of reagents

①High-fat (high-sugar) feeds

High-fat (high-sugar) feed ingredients: contains 10% sucrose, 10% lard, 5% cholesterol

High-fat and high-sugar feeds were made by combining basic rat feed with sucrose, condensed lard and egg yolk in the following mass ratio: 18 % lard, 20 % sucrose, 3 % egg yolk, and 59 % basic feed.

② Preparation of STZ solvent - sodium citrate buffer

Preparation of Liquid A and Liquid B: Weigh 2.1g of citric acid (FW:210.14) and add it to 100mL of double-distilled water to make Liquid A. Weigh 2.94g of sodium citrate (FW:294.10) and add it to 100mL of double-distilled water to make Liquid B.

Preparation of sodium citrate buffer: Mix A and B liquid in a certain proportion (1:1.32 or 1:1), pH meter to determine the pH value, adjust the pH value to 4.2-4.5, that is, the required sodium citrate buffer.

1.4 Preparation before injection

Before preparing STZ injection, STZ lyophilized powder was placed in a dry sterilized vial, wrapped externally with aluminum foil or tinfoil, pre-cooled in an ice bath with sodium citrate buffer, and brought to the animal room for backup.

Note: After removing the STZ lyophilized powder from the -20°C refrigerator, leave it dry and protected from light at room temperature for about 10min to allow it to thaw completely (very important).

1.5 Preparation of injection solution

Rats were weighed and blood glucose concentrations were measured after overnight fasting (no water). Rats were grouped in order to prepare the STZ injection according to the number of animals and the dose to be injected. Dissolve STZ at 1% concentration (w/V), filter and sterilize, keeping in mind that STZ is completely dissolved.

Attention:

①STZ is unstable and easy to inactivate, the remaining reagent after rapid weighing still requires drying and light protection, and it is recommended to wrap it with dry aluminum foil (or tin foil) paper.

②If you are not skilled in injection, do not dissolve the STZ at one time, and it is recommended that you dissolve the STZ in groups, such as 10 or 15 rats/group, depending on your skill level.

③The STZ can also be weighed in advance and dispensed in the amount required for animal grouping.

1.6 Injection

Inject intraperitoneally or caudal vein according to the fasting body weight of the animal. If the injection operation technique is not skillful, two groups should be injected alternately, and the injection should be completed within 30 minutes. Note: Most of the injections require rapid injection.

Attention:

Type I diabetes model: rat dose 70-65mg/kg

Type II diabetic model: Rats fed with high sugar and high fat for 1-2 months were treated with STZ at a dose of 25-40mg/kg.

1.7 After injection

After the injection of STZ, the animals should be given enough water and food (the basic living characteristics of diabetic rats), and the bedding needs to be changed daily to keep the cage dry. When feeding, take care to avoid strong sunlight. Sterilize as often as possible.

Note: After STZ modeling, fluctuations in apparent blood glucose levels show 3 temporal phases, transient hyperglycemia (1- 2h), transient hypoglycemia (6-10h), and persistent hyperglycemia (>72h). Insulin and glucose must be appropriately supplemented.

2.Indicators for assessing the modeling effect of STZ-induced diabetes modeling

The following indicators were counted in comparison with the control group:

1. Generalindicators:the phenomenon of excessive drinking, eating and urinating, and weight loss;
2. Otherindicators:fasting blood glucose, fasting serum insulin level, serum insulin level, insulin sensitivity, glucose tolerance and so on;
3. Serumbiochemicalindicators: T-Cho, TG, HDL-C, LDL-C, CR, BUN, Alt, etc.
4. Pathologicalslides:histopathological slides of the pancreas

3.Explanation of the reasons for the failure of the STZ-induced diabetes model

1. 1. thequality ofSTZ is the key, the purity of STZ for modeling should be not less than 98% (HPLC test).
2. 2. STZ failure: should be stored dry, avoid moisture. Avoid prolonged room temperature placement of the powder. DissolvedSTZis very unstable, with a half-life of 15 minutes at neutral  Pay attention to dissolve STZ with acidic pH, preferably in an ice bath.
3. Whether ornot the intraperitoneal injection is injected into the intestines and other organs.

If the model is not up to standard, it is recommended that, if the model is not up to standard, it should be re-injected for another 3 days.

4. Explanation of the causes of STZ-induced high mortality in mice/rats

4.1. The rat's weight is too low;

4.2. Enough drinking water must be guaranteed (insufficient drinking water can easily lead to dead rats).

4.3. High blood sugar and low blood sugar will cause dead rats, avoid dead rats can be injected by insulin or temporary sugar supplementation, two ways: ① Commonly high blood sugar. Insulin supplementation method, supplement some medium-acting insulin. For example, give Novolin N or NPH (neutral fish protein zinc insulin), 2-3 units each time, after 3-5 days, the general mortality rate of rats will be low; ②sugar supplementation method, after fasting rats, the injection has been in a hypoglycemic state, the molding of 4 hours after the intraperitoneal injection of 20% glucose, can be avoided due to the injection of hypoglycemia death of the rats;

4.4. Prevent animals from killing each other. Lack of food and insufficient water supply will tear each other apart and nibble on their own kind, so food and water should be supplied in sufficient quantities, preferably in two ways.

4.5.Prevent infection. Diabetic rats urinate a lot, the bedding is moist and needs to be changed frequently, so diabetic rats are more prone to infections than other rats, especially urinary tract infections and abdominal infections. Before and after invasive operations such as intraperitoneal injection, subcutaneous injection and blood glucose collection, attention should be paid to sterilization. For example, tetracycline (or gentamycin ophthalmic ointment) can be applied locally to treat the wound to prevent infection after each blood glucose collection.

5. Factors affecting diabetes modeling

The influencing factors of diabetes disease modeling include the quality of STZ modeling reagents, animal condition and administration method. Among them, the main properties of the reagents are purity, stability, solubility characteristics, etc. The animal condition mainly includes genetic background, male and female, gender, body weight, feeding environment, dietary structure, etc., and the mode of administration includes administration time, administration interval and administration route. Differentiated factors bring differentiated modeling effects.

6. The STZ modeling methodology ideas sorted out

Standardization of the influencing factors is a guarantee of achieving the modeling purpose and modeling stability.Theoretically, all animal modeling experiments require preexperimentation.

In the case of STZ-induced diabetes model, the dosage of STZ should refer to the results of the pre-tests, and try not to blindly follow the dosage in the literature or others to use directly, as the average weight of rats and fasting (low glucose state) resistance, the length of fasting, the timing of injections, as well as the previous feeding process, the time of glucose measurement, and so on, are different, and it is the most scientific to determine the dosing measurements in accordance with their own experimental mice through the pre-tests. The most scientific way is to determine the dosage of the drug by pre-testing.

7.High Modeling Success Rate STZ Usage Guidelines

STZ preservation, dissolution, dispensing and other precautions for use, see the official website of the relevant reagents.

8.Products

High success rate: purity ≥98% (HPLC determination); stable quality, cost-effective, spot supply, after-sale guarantee.

Product name	Catalog number	Specification
Streptozocin	60256ES60/76	100/500mg
Streptozocin	60256ES80	1g
Citric Acid, Monohydrate Citric Acid Monohydrate	60347ES25	25g
Citric Acid Trisodium Salt, Dihydrate	60348ES25	25g

(For more information on the use of STZ molding, please check the special article on yeasen website)

Product Line Published Articles (partial)

• Li, , Dong, J., Xiao, H., Zhang, S., Wang, B., Cui, M., & Fan, S. Gut commensal derived-valeric acid protects against radiation injuries. Gut Microbes,.2020 .1-18. IF=10.245
• Wang Y, Jia M, Yan X, et al. Increased neutrophil gelatinase-associated lipocalin (NGAL) promotes airway remodelling in chronic obstructive pulmonarydisease[J]. Clinical Science, 2017, 131(11): 1147-1159. IF=6.124
• Su J, Sun H, Meng Q, et  Enhanced Blood Suspensibility and Laser-Activated Tumor-specific Drug Release of Theranostic Mesoporous Silica Nanoparticles by Functionalizing with Erythrocyte Membranes[J]. Theranostics, 2017, 7(3): 523. IF=11.556
• Wu J, Lv Q, He J, et al. MicroRNA-188 suppresses G 1/S transition by targeting multiple cyclin/CDK complexes[J]. Cell Communication and Signaling,2014, 12(1): 66. IF=5.712
• ZhangT Q, Wang J  Shoot Regenerative Capacity Assays in Arabidopsis and Tobacco [J].The Plant Cell, 2015. IF=10.69
• YaoC, Ni Z, Gong C, et  Rocaglamide enhances NK cell-mediated killing of non-small cell lung cancer cells by inhibiting autophagy[J]. Autophagy, 2018, 14(10): 1831-1844. IF=16.016
• FanH, Chen W, Zhu J, et  Toosendanin alleviates dextran sulfate sodium-induced colitis by inhibiting M1 macrophage polarization and regulating NLRP3 inflammasome and Nrf2/HO-1 signaling[J]. International immunopharmacology, 2019, 76: 105909. IF=4.932
• Gao X , Fan W , Tan L , et al. Soy isoflavones ameliorate experimental colitis by targeting ERα/NLRP3 inflammasome pathways[J]. The Journal of Nutritional Biochemistry, 2020, 83. IF=6.048

Rheumatoid arthritis modeling

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease characterized by persistent synovitis, systemic inflammation, accompanied by bone and cartilage erosion, which can eventually lead to joint ankylation and deformity.

Freunds Adjuvant was invented by Jules Freund in the 40s of the 20th century, which is an antigen emulsion that mixes an equal amount of antigen aqueous solution with an oil and then adds an emulsifier to make water-in-oil, which is the most commonly used adjuvant in animal experiments. Freund's adjuvant is divided into Complete Freund's Adjuvant (CFA) containing Mycobacterium tuberculosis and Incomplete Freund's Adjuvant (IFA) without Mycobacterium tuberculosis, which are mainly used to induce collagen-induced arthritis CIA model and adjuvant-induced arthritis AA model in mice.

1.Collagen-induced arthritis (CIA) modeling steps (for reference only)

1) Prepare relevant reagents, pay attention to setting up the experimental group and the control group.

2) Bovine type 2 collagen (CII.) was dissolved in glacial acetic acid solution at a concentration of 2 mg/mL at 4°C overnight.

3) Freund's incomplete adjuvant was supplemented with inactivated Mycobacterium tuberculosis at a concentration of 2-5 mg/mL to prepare Freund's complete adjuvant. The concentration of Mycobacterium tuberculosis in the 60718ES Freund's complete adjuvant provided by Yisheng Biotech was less than 10 mg/mL.

4) Bovine collagen type 2 (CII.) acetic acid solution is mixed with an equal amount of Freund's complete adjuvant and emulsified.

5) Subcutaneous injection of 0.1-0.2 mL on the back of each experimental mouse.

6) After 3 weeks, the same amount of Fund incomplete adjuvant was mixed with bovine collagen type 2 (CII.) acetic acid solution and emulsified, and each mouse was injected subcutaneously at the base of the tail for a total of 0.1-0.2 mL.

7) Pathological examination: mice in the experimental group and the control group were removed, 4% formaldehyde was fixed for more than 48 h, 5% nitrate decalcified for 2 h, xylene infiltrated, and paraffin embedded. Sections were made, HE staining, and observed with conventional light microscopy.

2.Adjuvant-Induced Arthritis (AA) Modeling Steps (for reference only)

1) Prepare relevant reagents, pay attention to setting up the experimental group and the control group.

2) Observation record: Generally, 7-12 days after the second immunization, more than 80% of mice have arthritis symptoms. According to the redness, swelling and activity of the joint parts of the mice, the clinical symptoms were graded, and the observation records were observed before the experiment and on the 3rd, 5th, 7th, and 12th days after the experiment, respectively, and the grade classification reference is as follows:

Grade Index	Symptom
0	Activity is normal, no signs of erythema and swelling
1	Normal activity, redness of the skin, but no significant swelling
2	The activity is slightly affected, and there is redness and swelling in the paws and feet or knee joints
3	Activity is affected, and the paws, toes, or knees are mildly deformed, red, and swollen
4	Impaired movement, severe redness and swelling of the toes or knees of the feet, claws, toes, or knees, and stiffness or deformity

 

3) Mouse measurement: The volume of the hind limb joints of mice before and after the experiment was measured by using a mouse claw foot volume measuring meter, and the volume of the knee joints of the hind legs of each mouse was measured below about 5 mm, repeated three times, the average value was recorded, and the test was carried out once every three days.

4) Pathological examination: mice in the experimental group and the control group were removed, 4% formaldehyde was fixed for more than 48 h, 5% nitrate was decalcified for 2 h, xylene was infiltrated, and paraffin was embedded. Sections were made, HE staining, and observed with conventional light microscopy.

3.FAQ

Problems that may arise	Answer
What is the difference between 60718ES Freund's Complete Adjuvant (CFA) and 60719ES Freund's Incomplete Adjuvant (IFA)?	Freund's complete adjuvant (CFA) contains heat-killed, inactivated Mycobacterium tuberculosis bacilli that stimulate a strong immune response; Incomplete Freund's adjuvant (IFA) lacks Mycobacterium tuberculosis and stimulates a weaker immune response.
What is the specific amount of BCG in 60718ES Freund's Complete Adjuvant (CFA)?	The BCG content is less than 10 mg/mL.
When used for rheumatoid arthritis animal modeling, how to choose Freund's complete adjuvant (CFA) and Freund's incomplete adjuvant (IFA)?	Because rats are generally more sensitive than mice, mice are generally treated with CFA, and rats can also be treated with IFA, but CFA will be better used.

Related product recommendations

Classify	Product name	Catalog number	Specification
Rheumatoid arthritis model	Complete Freund's Adjuvant (CFA)	60718ES	10 mL/5x10 mL
	Incomplete Freund's Adjuvant (IFA)	60719ES	10 mL/5x10 mL

 

Hypertensive modeling

Hypertension is characterized by increased systemic arterial blood pressure (systolic and/or diastolic blood pressure), which is manifested in systemic arterial blood pressure (systolic blood pressure≥ 140 mmHg and/or diastolic blood pressure ≥90 mmHg), which is the most common chronic disease and the most important risk factor for cardiovascular and cerebrovascular diseases, and is often accompanied by clinical syndromes with functional or organic damage to heart, kidney, brain and other organs. The study of the prevention and treatment of hypertension is of great practical significance, and the establishment of animal hypertension model is an important part of the study of hypertension.

Animal hypertension models can be divided into genetically related models and non-genetically related models. Genetically related models include hereditary and genetically engineered animal models, while non-genetically related models generally refer to models induced by environmental, surgical, and drug factors. The research subjects of modeling generally include pigs, sheep, rabbits, dogs, mice and rats, etc., but most of the experiments are modeled in mice and rats, and the commonly used animal hypertension models are the SHR model of spontaneous hypertensive rats and the drug-induced hypertension model.

1. Animal hereditary hypertension model

1.1 SHR model of spontaneously hypertensive rats

Spontaneous hypertensive rats, also known as SHR rats, have an incidence of hypertension of nearly 100% and are the most widely used animal models. The systolic blood pressure of normal rats is 110-120 mmHg, and the blood pressure of SHR rats begins to increase after 4-6 weeks of age, and the blood pressure is as high as more than 200 mmHg after breeding.

Advantages: The incidence of hypertension is high, the course of the disease is short, and the pathological changes of the target organs during the onset can be observed.

Disadvantages: The breeding cycle is long, the feeding conditions have certain requirements, and the price is slightly more expensive than that of ordinary rats.

1.2 SHRsp model of stroke-prone spontaneous hypertension rats

Stroke-prone spontaneous hypertension rats, also known as SHRsp rats, have an incidence of hypertension of nearly 100% and stroke of nearly 80%. Blood pressure in SHRsp rats began to increase after 4-6 weeks of age, and could reach 200 mm Hg after 10-15 weeks of age.

Advantages: The incidence of hypertension is close to 100%, and the incidence of stroke is 80%, which is an ideal animal model for stroke research.

Disadvantages: long cultivation cycle, troublesome genetic breeding, easy to mutate, breakage.

2. Drug-induced hypertension model

2.1 Angiotensin II (AngII.) induction

2.1.1 Experimental methods (for reference only)

Male mice aged 8-12 weeks were injected with angiotensin II and normal saline by osmotic pump subcutaneous injection, and the dose of AngII was generally 100 ng/(kg·min) for 2-4 weeks. The administration time can be shortened or extended accordingly according to the actual situation.

2.1.2 Experimental pictures (excerpts from the literature)

Application 1: Angiotensin II. mice fed with NaCl solution for 28 days, the experimental group compared with the control group, the blood pressure increased significantly.

Fig.5 Changes in blood pressure and heart rate in mice (A is systolic blood pressure, B is average blood pressure, C is diastolic blood pressure, D is heart rate)

2.2 Deoxycorticosterone acetate (DOCA) induction

Deoxycorticosterone acetate (DOCA) can inhibit the renin-angiotensin system, resulting in low plasma renin activity, thereby mediating an increase in blood pressure, generally by implanting a subcutaneous DOCA extended-release pump or injecting DOCA, and adding NaCl solution to induce the formation of hypertension.

It is mainly applicable to the research of renin-angiotensin system (RAS) and water and sodium metabolism in hypertension, and the model can make the blood pressure increase stably and the method is simple.

2.2.1 Experimental methods (for reference only)

The left kidney of 250-275 g normal male rats was resected, and the rubber medium made of DOCA and silica gel was placed under the skin between the shoulder blades on both sides of the rat, or after the left kidney was removed, DOCA was injected subcutaneously at 50 mg/(kg·d) per day, and it should be noted that the DOCA rats needed to drink 1% NaCl solution during the feeding process, and the blood pressure of the rats was measured after 3-5 weeks of operation.

2.2.2 Experimental pictures (excerpts from the literature)

Application 1: After the unilateral kidney was removed, DOCA was added, and the results showed that the blood pressure of the mice in the control group was relatively constant, but the blood pressure of the mice in the experimental group increased significantly.

Fig.6 Diagram of blood pressure changes in mice

2.3 N-nitro-L-arginine methyl ester (L-NAME)-induced animal model of hypertension

L-NAME is a competitive inhibitor of nitric oxide synthase, an active substance that promotes endothelial function and decreases blood pressure when nitric oxide rises. L-NAME, a competitive inhibitor of nitric oxide synthase, can weaken the vasodilatory effect of nitric oxide and lead to the occurrence of hypertension. Therefore, an animal model of hypertension caused by long-term NO deficiency can be established, and the model experimental research objects are mostly seen in rats.

It is mainly suitable for the study of nitric oxide system and cardiovascular system in hypertension, and the model can make the blood pressure rise stably and continuously, and the method is simple.

2.3.1 Experimental methods (for reference only)

Male rats aged 3-4 weeks were intraperitoneally injected (or gaved) with L-NAME at 20-50 mg/(kg·d) and administered once a day for 4 weeks, and the control group was only intraperitoneally injected (or gaved) with distilled water, and the changes of the rats were monitored daily.

After the experiment, the body weight, blood pressure, heart rate, serum biochemical indexes and other biochemical indexes of the experimental group and the control group were measured.

2.3.2 Experimental tables and pictures (excerpts from the literature)

Application 1: After enrollment, the blood pressure of the model group gradually increased with the extension of L-NAME intake time, and reached the standard of hypertension at the 4th week, which was significantly higher than that of the corresponding control group.

Application 2: Hypertension was formed after 4 weeks of irrigation in rats, which was significantly higher than that of rats in the corresponding control group, and the aqueous extract of cassia seed could reduce pressure and improve kidney lesions.

2.4 Comparison of drug-induced hypertension models

Drug-induced hypertension model	Angiotensin II. （AngⅡ）	Deoxycorticosterone acetate （DOCA）	N-Nitro-L-Arginine Methyl Ester (L-NAME)
Description of the method	Osmotic pump subcutaneous injection, AngII. dose is generally 100 ng/(kg·min)	First, the unilateral kidney was resected, and 50 mg/(kg·d) DOCA was injected subcutaneously, and 1% NaCI solution was drunk at the same time	Intraperitoneal injection (or gavage) of 20-50 mg/(kg·d) L-NAME, such as drinking 1% NaCI solution, can accelerate molding
Mold cycle	2-4 weeks	3-5 weeks	4-5 weeks
Application scenarios	Research on oxidative stress damage and RAS	RAS related studies and sodium water Metabolism-related research	NO system, cardiovascular system-related research

 

Related Product Recommendations (Summary)

Classify	Product name	Catalog number	Specification
Hypertension model	L-NAME hydrochloride(L-NAME HCl)	52302ES	100 mg
	Angiotensin II human	54041ES	10 mg
	Deoxycorticosterone Acetate	54344ES	50 mg/500 mg
Rheumatoid arthritis model	Complete Freund's Adjuvant (CFA)	60718ES	10 mL/5x10 mL
	Incomplete Freund's Adjuvant (IFA)	60719ES	10 mL/5x10 mL
Colitis model	Dextran Sulfate Sodium Salt(DSS) MW:36000~50000 DSS Colitis modeling grade	60316ES	25 g/100 g/500 g/1 kg
Animal model of acute pancreatitis	Caerulein	60321ES	1 mg
Diabetic Disease Model	Streptozocin (STZ)	60256ES	100 mg/500 mg/1 g

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