论文部分内容阅读
Abstract [Objectives]This study was conducted to study the antigout effect of Phellodendron amurense and its different processed products.
[Methods]Extracts of P. amurense and its different processed products were fed to rats respectively, to observe uric acid and creatinine in the serum and swelling index.
[Results]Compared with the data of positive control, P. amurense and the processed products could significantly reduce the high uric acid and creatinine in the serum, and also could resist the swelling in rats.
[Conclusions]P. amurense and its processed products showed different degrees of antigout effect, and the processing methods were found to have no remarkable impact on this effect.
Key words Phellodendron amurense; Antigout effect; Processed products; Hyperuricemia
Gout is a kind of metabolic disease closely related to hyperuricemia, which is caused by the settlement of monosodium urate (MSU) on joints and surrounding connective tissues due to excessive uric acid or reduced excretion of uric acid. Hyperuricemia is the precondition and biochemistry of gout which is inevitably accompanied by hyperuricemia, and therefore, for the control of gout, hyperuricemia and gout are often discussed together. With the continuous improvement of people’s living standard and the change dietary structure and living habit, the incidence rates of hyperuricemia and gout increase year by year[1]. Therefore, the development of medicines for the prevention and control of gout and hyperuricemia has become one of the hotspots in the research of gout.
Currently, gout is mainly treated with colchicine, nonsteroid antiinflammatory drugs, corticosteroids, adrenocorticotrophic hormone, xanthine oxidase and xanthine dehydrogenase inhibitors. These drugs play a role in controlling symptoms and stabilizing the disease to a certain extent, but they have many adverse effects, such as nausea, vomiting, diarrhea, allergic reaction, liver and kidney damage, etc. For instance, the effective dose of colchicine in the treatment of gout is proximate to the dose causing gastrointestinal symptom. Therefore, scholars at home and abroad have been researching and searching for new highlyeffective lowtoxic drugs. The traditional Chinese medicine (TCM) theory deems that gout belongs to pyretic arthralgia when it acutely attack human body[2-3], and it is treated mainly with dampclearing, painrelieving and kidneynourishing traditional Chinese medicines[4], among which Phellodendron amurense is a medicine commonly used. In Chinese pharmacopoeia (2015 version), "Ermiao Wan" and "Sanmiao Wan" for treating gout both take P. amurense as the main material, and therefore, the potential value of P. amurense in treating gout attracts more and more attention. P. amurense is the dry bark of P. amurense Rupr. and P. chinense Schneid. in Rutaceae family. It has the effects of clearing away heat and drying dampness, purging intense heat, and curing furuncles. The traditional processing theory deems that processing P. chinense with salt could alleviate its bitter taste and reduce its cold nature, thereby enhancing its effects of clearing heat and drying dampness. P. chinense contains alkaloids, among which berberine is a main component, which accounts for 72.27%-90.64% of the total content of alkaloids[5]. In early period, the components in raw P. chinense, salt P. chinense and plaindried P. chinense were separated by HPLC separation, and it was found that the salt processed product contained very low berberine content, but contained 28.30% of berberrabine converted from berberine, the plainfried P. chinense had the berberine content as low as 3.78% and berberrabine content of 14.36%[6]. Whether the salt processing method or the processing methods affect the effect of P. chinense in treating gout and have synergistic effect, has not been systematically understood. In this study, directing at uric acid and the acute arthritis caused by it, an animal experiment was carried out to discuss the antigout effect of P. chinense and its processed products, and investigate the change in the pharmaceutical effect before and after the processing of P. chinense. This study will provide a basis for the expounding of the processing mechanism of P. chinense.
Materials and Methods
Materials
Colchicine Tablet (Yunnan Phytopharmaceutical Co., Ltd., 0.5 mg/table; lot number: 20070601); adenine, ethambutol, uric acid, pentobarbital sodium (SIGMA, Shanghai); blood uric acid test kit (Nanjing Jiancheng Bioengineering Institute, lot number: 200701108); P. chinense, purchased from Sichuan Medicinal Material Company, identified by professor Wang from the teaching and research section of medicinal plants, Liaoning University of Traditional Chinese Medicine to be dry bark of P. chinense Schneid in Rutaceae.
Sample preparation
Saltprocessed P. chinense: The salt processing was performed according to Chinese Pharmacopoeia (2010 edition). Shredded P. chinense with uniform size was placed in a suitable container, sprayed with salt water and mixed well. The P. chinense was moistened in a closed sate for 2 h. At the temperature of 150-160 ℃, the P. chinense was fried in a pot for 6 min, taken out and cooled. Salt was used according to 5 kg per 100 g of P. chinense and dissolved in 30 L of water. Plainfried P. chinense: Without adding salt and moistening, the shredded P. chinense was processed in a pot according to the temperature and time of the optimal salt processing method.
Preparation of water decoction: Each of the processed products was decocted in water for two times, and filtrates were merged and concentrated to extract (1 ml equal to 1 g of raw drug) which was preserved in a refrigerator.
Experimental animals
140 adult male SD rats (half male half female) with a body weight of (220±24) g were purchased from China Medical University, with the License number: SCXK(Liao)20020002. The environment of the experimental animals was of clean class.
Instruments
Hitachi 7080 fully automatic biochemical analyzer; EasyTouch blood glucose uric acid difunctional tester (EASYTOUCH, Taiwan).
Experimental methods
Effects of samples on uric acid and creatinine in blood of hyperuricemia model rate (test 1)
Test grouping
Sixty SD rats adaptively raised for 1 week were randomly selected and divided into the blank control group, the hyperuricemia model group (model group), colchicine treatment group (positive control group), salt P. chinense treatment group (salt P. chinense group), raw P. chinense treatment group(raw P. chinense group) and plainfried P. chinense treatment group (plainfried P. chinense group), each of which included 10 rats.
Effect of sample on experimental acute gouty arthritis model rats (test 2)
Sixty SD rats adaptively raised for 1 week were randomly selected, and grouping was performed according to "Test grouping".
Modeling method
Hyperuricemia rat model
Blank control was given equal volume of water by gavage, and animals in other groups were given adenine (200 mg/kg) and ethambutol (250 mg/kg) by gavage for 7 d continuously, resulting in hyperuricemia rats.
Acute gouty arthritis rat model
Preparation of sodium urate: According to McCARTY D.J. method, 8 g of uric acid was dissolved in 1 600 ml of distilled water. Then, 49 ml of 1 mol/L NaOH was added into the solution, followed by stirring with a magnetic bar to cool the solution, and the pH value was adjusted with l mol/L HCl to 7.2. The solution was placed in a refrigerator at 4 ℃ for 24 h, the supernatant was discarded, and water on the precipitate was absorbed with water. The precipitate was dried at 60 ℃ for 24 h, obtaining the sodium urate crystal. The sodium urate was subjected to autoclaved sterilization, and prepared to 100 g/L suspension with normal saline. According to the typical method of CODENE et al. with some modification, animals were given agents. Except the blank control group, rats in other groups were all administered pentobarbital sodium (40 mg/kg) by intraperitoneal injection to anesthetize them. The rear part of the right ankle joint was selected as the puncture point, which was disinfected with 75% and punctured using No. 4.5 syringe needle with the slant upwards forming an angle of 45° with the shin bone to inject 100 g/L (0.1g/ml) sodium urate suspension until the offside of the joint capsule plumped up, so as to induce acute arthritis model. The normal control group was injected with equal volume of PBS buffer.
Administration method
Test 1
Five days before modeling, except that the blank and model groups were given equal amount of distilled water, other groups were subjected to intragastric adminstration. According to the reduction formula of human drug dose and experimental animal drug dose, the dosage of administration of each rate was calculated. Each rat was administrated adenine 200 mg/kg and ethambutol 250 mg/kg once daily. From the 6th day, intragastric adminstration was performed in the morning, modeling was carried out in the afternoon, the operations were continued for 7 d, and on the 7th day, intragastric adminstration was performed 0.5 h before modeling, once.
Test 2
The normal control group was administrated 2 ml of normal saline every day by gavage, continuously for 10 d. The model group was administrated 2 ml of normal saline every day by gavage, continuously for 10 d, and injected with 0.19 ml of sodium urate suspension subcutaneously at the hind foot compartment to induce inflammation. The positive control group was administrated colchicine (0.6 g/kg) dissolved in 2 ml of normal saline for 10 d continuously. The rats in the salt, raw and painfried P. chinense groups were administrated salt, raw and plainfried P. chinense solutions, respectively, for 10 d, at the gavage doses converted according to adult doses.
Detection of uric acid and creatinine concentrations in serum
At first, 0.5 h after modeling, rats in various groups were administrated pentobarbital sodium (40 mg/kg) by intraperitoneal injection to anesthetize them. Then blood was collected from postglomus venous plexus and stood in a water bath at 37 ℃ to layering, and centrifugation was performed at 2 500 r/min for 10 min, obtaining serum for later use. The operation was completed with the assistance of the Clinical Laboratory of the First Hospital of Liaoning University of Traditional Chinese Medicine. Determination of joint swelling index
At first, foot swelling was detected 1, 2, 4 and 24 h after modeling. The volume of foot volume was represented by volume of drained water (ml), and the change of foot volume (the difference of drained water before and after induction of inflammation) represents the swelling degree.
Swelling degree∥%=(Volume of the right hind foot of rat after modelingVolume of the right hind foot of rat before modeling)/Volume of the right hind foot of rat before modeling×100%
Methods for statistical processing of data
The data were represented as X±SD. Statistical analysis was performed in SPSS13.0, and ANOVA test was performed.
Results and Analysis
Effects on uric acid and creatinine in blood of hyperuricemia model
In the test, no animals died and suffered from terminal loss. The uric acid and creatinine concentrations in the blood of rats in the model group were significantly higher than those in the blank control group (P<0.01), while the levels in other groups had no remarkable differences from the blank control group (P>0.05). The data are shown in Table 1.
2.2 Swelling degree of the right foot of rats in test 2
General comparison
After induction of inflammation, the rats exhibited swollen feet which could not tough the ground, and they could not walk steadily, and squealed sometimes. Above symptoms were remarkably improved after treatment, accompanied by improved urine volume.
Comparison of swelling degree of the right foot after the induction of inflammation
After the induction of inflammation, the rats in the model group showed remarkable swelling, which was the most severe at 8 h and slightly alleviated after 24 h. The swelling conditions of rats in the positive control group, salt P. chinense group, raw P. chinense group and fried P. chinense group were basically the same in corresponding time. The data are shown in Table 2.
Agricultural Biotechnology2018
Results and Discussion
Gout is a kind of heterogeneous disease caused by hyperuricemia produced due to uric acid metabolism disorder. The TCM theory deems that uric acid would poison organisms if it is accumulated excessively in body, and the disease is caused by turbid dampness, and treated according to the principle of clearing heat and promoting diuresis, and dispelling the wind and relieving rheumatic pains. P. chinense tastes bitter, and is cold in nature, and effective on the kidney. The medicinal material has the effects of clearing away heat and drying dampness, and purging fire for removing toxin. In this study, it was found that the uric acid and creatinine concentrations in hyperuricemia model rats increased remarkably, the joints of the experimental acute gouty arthritis model rats swelled remarkably, while the colchicine, salt P. chinense, raw P. chinense, and fried P. chinense all could remarkably reduce the uric acid and creatinine levels in hyperuricemia model rats, and inhibit swelling of joint, indicating that P. chinense has antigout effect. According to the research results of chemical components, after salt processing of P. chinense, berberine is converted to berberrubine. After the plain frying of P. chinense, the content of berberine is reduced, but meanwhile, berberrubine is produced. However, the change of components in P. chinense was not correlated with its antigout effect, or whether the berberine type of alkaloids are the main effective components still needs further study. In addition, no differences were observed in antigout effect between different processed P. chinense products, which might be due to that the high, medium and low dose contrast groups were not set. Furthermore, because the toxic and side effect of P. chinense is lower than colchicine, its antigout value still should be further explored.
References
[1]SURESH E. Diagnosis and management of gout: a rational approach[J]. Postgrad Med, 2005, 81: 572-579.
[2]XU SL. Syndrome differentiation and treatment of gout[J]. Chinese Journal of Traditional Medical Traumatology & Orthopedics, 1993, 1(4): 21. (in Chinese)
[3]WAN TB. Experience of professor Liu in treatment of gout with Tongfeng Dingtong Soup[J]. Journal of Nanjing University of Traditional Chinese Medicine, 1994, 10(4): 18. (in Chinese)
[4]ZHAI LM. 27 cases of treating hyperuricemia with traditional Chinese medicine[J]. Journal of Traditional Chinese Medicine, 2007(6): 54-55. (in Chinese)
[5]DONG YQ, HE XH, ZHONG GY. Discussion of the situation and problems of quality research of Phellodendron chinense[J]. Research and Practice on Chinese Medicines, 2007,22(3):58-61. (in Chinese)
[6]LIAN L. Study on the processing principle of Phellodendron chinense[D]. Shenyang: Liaoning University of Traditional Chinese Medicine, 2008. (in Chinese)
Editor: Yingzhi GUANG Proofreader: Xinxiu ZHU
[Methods]Extracts of P. amurense and its different processed products were fed to rats respectively, to observe uric acid and creatinine in the serum and swelling index.
[Results]Compared with the data of positive control, P. amurense and the processed products could significantly reduce the high uric acid and creatinine in the serum, and also could resist the swelling in rats.
[Conclusions]P. amurense and its processed products showed different degrees of antigout effect, and the processing methods were found to have no remarkable impact on this effect.
Key words Phellodendron amurense; Antigout effect; Processed products; Hyperuricemia
Gout is a kind of metabolic disease closely related to hyperuricemia, which is caused by the settlement of monosodium urate (MSU) on joints and surrounding connective tissues due to excessive uric acid or reduced excretion of uric acid. Hyperuricemia is the precondition and biochemistry of gout which is inevitably accompanied by hyperuricemia, and therefore, for the control of gout, hyperuricemia and gout are often discussed together. With the continuous improvement of people’s living standard and the change dietary structure and living habit, the incidence rates of hyperuricemia and gout increase year by year[1]. Therefore, the development of medicines for the prevention and control of gout and hyperuricemia has become one of the hotspots in the research of gout.
Currently, gout is mainly treated with colchicine, nonsteroid antiinflammatory drugs, corticosteroids, adrenocorticotrophic hormone, xanthine oxidase and xanthine dehydrogenase inhibitors. These drugs play a role in controlling symptoms and stabilizing the disease to a certain extent, but they have many adverse effects, such as nausea, vomiting, diarrhea, allergic reaction, liver and kidney damage, etc. For instance, the effective dose of colchicine in the treatment of gout is proximate to the dose causing gastrointestinal symptom. Therefore, scholars at home and abroad have been researching and searching for new highlyeffective lowtoxic drugs. The traditional Chinese medicine (TCM) theory deems that gout belongs to pyretic arthralgia when it acutely attack human body[2-3], and it is treated mainly with dampclearing, painrelieving and kidneynourishing traditional Chinese medicines[4], among which Phellodendron amurense is a medicine commonly used. In Chinese pharmacopoeia (2015 version), "Ermiao Wan" and "Sanmiao Wan" for treating gout both take P. amurense as the main material, and therefore, the potential value of P. amurense in treating gout attracts more and more attention. P. amurense is the dry bark of P. amurense Rupr. and P. chinense Schneid. in Rutaceae family. It has the effects of clearing away heat and drying dampness, purging intense heat, and curing furuncles. The traditional processing theory deems that processing P. chinense with salt could alleviate its bitter taste and reduce its cold nature, thereby enhancing its effects of clearing heat and drying dampness. P. chinense contains alkaloids, among which berberine is a main component, which accounts for 72.27%-90.64% of the total content of alkaloids[5]. In early period, the components in raw P. chinense, salt P. chinense and plaindried P. chinense were separated by HPLC separation, and it was found that the salt processed product contained very low berberine content, but contained 28.30% of berberrabine converted from berberine, the plainfried P. chinense had the berberine content as low as 3.78% and berberrabine content of 14.36%[6]. Whether the salt processing method or the processing methods affect the effect of P. chinense in treating gout and have synergistic effect, has not been systematically understood. In this study, directing at uric acid and the acute arthritis caused by it, an animal experiment was carried out to discuss the antigout effect of P. chinense and its processed products, and investigate the change in the pharmaceutical effect before and after the processing of P. chinense. This study will provide a basis for the expounding of the processing mechanism of P. chinense.
Materials and Methods
Materials
Colchicine Tablet (Yunnan Phytopharmaceutical Co., Ltd., 0.5 mg/table; lot number: 20070601); adenine, ethambutol, uric acid, pentobarbital sodium (SIGMA, Shanghai); blood uric acid test kit (Nanjing Jiancheng Bioengineering Institute, lot number: 200701108); P. chinense, purchased from Sichuan Medicinal Material Company, identified by professor Wang from the teaching and research section of medicinal plants, Liaoning University of Traditional Chinese Medicine to be dry bark of P. chinense Schneid in Rutaceae.
Sample preparation
Saltprocessed P. chinense: The salt processing was performed according to Chinese Pharmacopoeia (2010 edition). Shredded P. chinense with uniform size was placed in a suitable container, sprayed with salt water and mixed well. The P. chinense was moistened in a closed sate for 2 h. At the temperature of 150-160 ℃, the P. chinense was fried in a pot for 6 min, taken out and cooled. Salt was used according to 5 kg per 100 g of P. chinense and dissolved in 30 L of water. Plainfried P. chinense: Without adding salt and moistening, the shredded P. chinense was processed in a pot according to the temperature and time of the optimal salt processing method.
Preparation of water decoction: Each of the processed products was decocted in water for two times, and filtrates were merged and concentrated to extract (1 ml equal to 1 g of raw drug) which was preserved in a refrigerator.
Experimental animals
140 adult male SD rats (half male half female) with a body weight of (220±24) g were purchased from China Medical University, with the License number: SCXK(Liao)20020002. The environment of the experimental animals was of clean class.
Instruments
Hitachi 7080 fully automatic biochemical analyzer; EasyTouch blood glucose uric acid difunctional tester (EASYTOUCH, Taiwan).
Experimental methods
Effects of samples on uric acid and creatinine in blood of hyperuricemia model rate (test 1)
Test grouping
Sixty SD rats adaptively raised for 1 week were randomly selected and divided into the blank control group, the hyperuricemia model group (model group), colchicine treatment group (positive control group), salt P. chinense treatment group (salt P. chinense group), raw P. chinense treatment group(raw P. chinense group) and plainfried P. chinense treatment group (plainfried P. chinense group), each of which included 10 rats.
Effect of sample on experimental acute gouty arthritis model rats (test 2)
Sixty SD rats adaptively raised for 1 week were randomly selected, and grouping was performed according to "Test grouping".
Modeling method
Hyperuricemia rat model
Blank control was given equal volume of water by gavage, and animals in other groups were given adenine (200 mg/kg) and ethambutol (250 mg/kg) by gavage for 7 d continuously, resulting in hyperuricemia rats.
Acute gouty arthritis rat model
Preparation of sodium urate: According to McCARTY D.J. method, 8 g of uric acid was dissolved in 1 600 ml of distilled water. Then, 49 ml of 1 mol/L NaOH was added into the solution, followed by stirring with a magnetic bar to cool the solution, and the pH value was adjusted with l mol/L HCl to 7.2. The solution was placed in a refrigerator at 4 ℃ for 24 h, the supernatant was discarded, and water on the precipitate was absorbed with water. The precipitate was dried at 60 ℃ for 24 h, obtaining the sodium urate crystal. The sodium urate was subjected to autoclaved sterilization, and prepared to 100 g/L suspension with normal saline. According to the typical method of CODENE et al. with some modification, animals were given agents. Except the blank control group, rats in other groups were all administered pentobarbital sodium (40 mg/kg) by intraperitoneal injection to anesthetize them. The rear part of the right ankle joint was selected as the puncture point, which was disinfected with 75% and punctured using No. 4.5 syringe needle with the slant upwards forming an angle of 45° with the shin bone to inject 100 g/L (0.1g/ml) sodium urate suspension until the offside of the joint capsule plumped up, so as to induce acute arthritis model. The normal control group was injected with equal volume of PBS buffer.
Administration method
Test 1
Five days before modeling, except that the blank and model groups were given equal amount of distilled water, other groups were subjected to intragastric adminstration. According to the reduction formula of human drug dose and experimental animal drug dose, the dosage of administration of each rate was calculated. Each rat was administrated adenine 200 mg/kg and ethambutol 250 mg/kg once daily. From the 6th day, intragastric adminstration was performed in the morning, modeling was carried out in the afternoon, the operations were continued for 7 d, and on the 7th day, intragastric adminstration was performed 0.5 h before modeling, once.
Test 2
The normal control group was administrated 2 ml of normal saline every day by gavage, continuously for 10 d. The model group was administrated 2 ml of normal saline every day by gavage, continuously for 10 d, and injected with 0.19 ml of sodium urate suspension subcutaneously at the hind foot compartment to induce inflammation. The positive control group was administrated colchicine (0.6 g/kg) dissolved in 2 ml of normal saline for 10 d continuously. The rats in the salt, raw and painfried P. chinense groups were administrated salt, raw and plainfried P. chinense solutions, respectively, for 10 d, at the gavage doses converted according to adult doses.
Detection of uric acid and creatinine concentrations in serum
At first, 0.5 h after modeling, rats in various groups were administrated pentobarbital sodium (40 mg/kg) by intraperitoneal injection to anesthetize them. Then blood was collected from postglomus venous plexus and stood in a water bath at 37 ℃ to layering, and centrifugation was performed at 2 500 r/min for 10 min, obtaining serum for later use. The operation was completed with the assistance of the Clinical Laboratory of the First Hospital of Liaoning University of Traditional Chinese Medicine. Determination of joint swelling index
At first, foot swelling was detected 1, 2, 4 and 24 h after modeling. The volume of foot volume was represented by volume of drained water (ml), and the change of foot volume (the difference of drained water before and after induction of inflammation) represents the swelling degree.
Swelling degree∥%=(Volume of the right hind foot of rat after modelingVolume of the right hind foot of rat before modeling)/Volume of the right hind foot of rat before modeling×100%
Methods for statistical processing of data
The data were represented as X±SD. Statistical analysis was performed in SPSS13.0, and ANOVA test was performed.
Results and Analysis
Effects on uric acid and creatinine in blood of hyperuricemia model
In the test, no animals died and suffered from terminal loss. The uric acid and creatinine concentrations in the blood of rats in the model group were significantly higher than those in the blank control group (P<0.01), while the levels in other groups had no remarkable differences from the blank control group (P>0.05). The data are shown in Table 1.
2.2 Swelling degree of the right foot of rats in test 2
General comparison
After induction of inflammation, the rats exhibited swollen feet which could not tough the ground, and they could not walk steadily, and squealed sometimes. Above symptoms were remarkably improved after treatment, accompanied by improved urine volume.
Comparison of swelling degree of the right foot after the induction of inflammation
After the induction of inflammation, the rats in the model group showed remarkable swelling, which was the most severe at 8 h and slightly alleviated after 24 h. The swelling conditions of rats in the positive control group, salt P. chinense group, raw P. chinense group and fried P. chinense group were basically the same in corresponding time. The data are shown in Table 2.
Agricultural Biotechnology2018
Results and Discussion
Gout is a kind of heterogeneous disease caused by hyperuricemia produced due to uric acid metabolism disorder. The TCM theory deems that uric acid would poison organisms if it is accumulated excessively in body, and the disease is caused by turbid dampness, and treated according to the principle of clearing heat and promoting diuresis, and dispelling the wind and relieving rheumatic pains. P. chinense tastes bitter, and is cold in nature, and effective on the kidney. The medicinal material has the effects of clearing away heat and drying dampness, and purging fire for removing toxin. In this study, it was found that the uric acid and creatinine concentrations in hyperuricemia model rats increased remarkably, the joints of the experimental acute gouty arthritis model rats swelled remarkably, while the colchicine, salt P. chinense, raw P. chinense, and fried P. chinense all could remarkably reduce the uric acid and creatinine levels in hyperuricemia model rats, and inhibit swelling of joint, indicating that P. chinense has antigout effect. According to the research results of chemical components, after salt processing of P. chinense, berberine is converted to berberrubine. After the plain frying of P. chinense, the content of berberine is reduced, but meanwhile, berberrubine is produced. However, the change of components in P. chinense was not correlated with its antigout effect, or whether the berberine type of alkaloids are the main effective components still needs further study. In addition, no differences were observed in antigout effect between different processed P. chinense products, which might be due to that the high, medium and low dose contrast groups were not set. Furthermore, because the toxic and side effect of P. chinense is lower than colchicine, its antigout value still should be further explored.
References
[1]SURESH E. Diagnosis and management of gout: a rational approach[J]. Postgrad Med, 2005, 81: 572-579.
[2]XU SL. Syndrome differentiation and treatment of gout[J]. Chinese Journal of Traditional Medical Traumatology & Orthopedics, 1993, 1(4): 21. (in Chinese)
[3]WAN TB. Experience of professor Liu in treatment of gout with Tongfeng Dingtong Soup[J]. Journal of Nanjing University of Traditional Chinese Medicine, 1994, 10(4): 18. (in Chinese)
[4]ZHAI LM. 27 cases of treating hyperuricemia with traditional Chinese medicine[J]. Journal of Traditional Chinese Medicine, 2007(6): 54-55. (in Chinese)
[5]DONG YQ, HE XH, ZHONG GY. Discussion of the situation and problems of quality research of Phellodendron chinense[J]. Research and Practice on Chinese Medicines, 2007,22(3):58-61. (in Chinese)
[6]LIAN L. Study on the processing principle of Phellodendron chinense[D]. Shenyang: Liaoning University of Traditional Chinese Medicine, 2008. (in Chinese)
Editor: Yingzhi GUANG Proofreader: Xinxiu ZHU