Explore the direct and/or the synergistic antihypertensive effects of wind-dispelling herbs involving Fangfeng and Baizhi on hypertensive rats with liver-yang hyperactivity based on vasoactive substances

Bo Liang,Feng-Ying Luo,Hui-Ling Liao*

1School of Integrated Traditional and Western Medicine of Southwest Medical University;2Hospital(T.C.M)Affiliated to Southwest Medical University,Luzhou,Sichuan,China.

Abstract Objective:To explore the direct and/or the enhancing antihypertensive effects of wind-dispelling herbs involving Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix)using liver-yang hyperactivity renal hypertension rat.M ethods:Model rats with hyperactivity of liver-yang hyperactivity were prepared using male SD rats.Once successful,the rats were random ly divided into groups and given medicine by gavage for 4 weeks.Blood was collected from the abdom inal aorta to prepare serum.Serum nitric oxide(NO)concentration was determined by chemical colorimetry.The contents of ET,TXB2 and 6-K-PGF1a were determined by enzyme linked immunosorbent assay(ELISA).Results:Compared with the control model group,the blood pressure,serum ET and TXB2 of rats in the wind dispelling medicine group was not significantly reduced,while those of rats in captopril group,Tianma Gouteng Decoction I group(TGD group)decreased significantly(P＜0.05 for both).Interestingly,the blood pressure,serum ET and TXB2 of rats in the combination group(wind dispelling medicine&TGD)decreased significantly compared with both wind dispelling medicine group and TGD group.Meanwhile,the levels of serum NO and 6-K-PGF1a in the combination group was much higher than those in the wind dispelling medicine group or TGD group(P＜0.05 for both).However,the levels of serum NO and 6-K-PGF1a in the wind dispelling medicine group was not significantly increased compared with the model group.Conclusion:There is no direct pressure lowering effects of wind dispelling medicine alone,while wind dispelling medicine could potentiates the antihypertensive effects of Tianma Gouteng Decoction I.Besides,the synergistic effects may be related to decreased ET and TXB2 levels and the increased NO and 6-K-PGF1a levels.

Keywords:Liver-yang hyperactivity renal hypertension,Vasoactive substances;Wind dispelling medicine(Fangfeng(Saposhnikoviae Radix),Baizhi(Angelicae dahuricae Radix)),Synergistic antihypertensive mechanism

Background

Hypertension is a cardiovascular syndrome characterized by elevated system ic arterial pressure and is defined as a systolic blood pressure of≥140 mmHg and/or diastolic blood pressure of≥90 mmHg without antihypertensive drugs[1].Since 1950s,the prevalence of hypertension in our country has been on the rise,accounting for one-fifth of the people suffering the disease in the world.However,the rates of awareness,treatment and control are very low[2-4].In our country,nearly half of 35-75-year-old patients have high blood pressure,one-in-three of which receive treatment,and only less than one-in-twelve of the patients receiving treatment had good blood pressure control[5].Therefore,it’s urgent to improve the treatment of hypertension.Chinese medicine has a long history and has accumulated rich experience in this field.Tianma Gouteng Decoction(TGD)with the effect of Ping Gan Qian Yang is derived from the book“M iscellaneous Diseases Zheng Governance New Meaning”w ritten by Huguangci.In recent years,the formula in clinical was used to treat hypertension in patients caused by liver-yang hyperactivity with obvious antihypertensive effect.Orthogonal experimental design was adopted to confirm that orthogonal 1 formula(TGD)can increase the antihypertensive effect[6].The pathological mechanism of hypertensive vascular remodeling is complex,and mainly related with the release of vasoconstrictric substances,decreasing the secretion of vasorelaxant substances and other factors.Therefore,maintaining the balance of the vasomotor factor,ie,the homeostasis of nitric oxide(NO)/endothelin(ET)and thromboxane B2(TXB2)/6-keto-prostaglandin F1a(6-K-PGF1a)should be of great concern.In recent years,the combination of traditional Chinese and western medicine has made great achievements in the treatment of hypertension.Relevant clinical studies have confirmed that the treatment of hypertension with wind dispelling medicines or combined with wind dispelling medicines has significant effect[7,8].However,the study of wind dispelling medicine induced synergistic antihypertensive effect and the mechanism of that based on vasoactive substances is less reported.In this experiment,the model of hypertensive rat with liver-yang hyperactivity was established to observe the effect of the wind dispelling medicine on the blood pressure of the hypertensive rats and to evaluate the synergistic antihypertensive effect.By detecting the change of NO,ET,TXB2 and 6-K-PGF1a,we initially explored the mechanism of antihypertensive effect of wind medicine,and provided the experimental basis and theoretical basis for the clinical application of“wind dispelling medicine”in treatment of hypertension.

M aterials and Methods

Experimental animals

100 healthy 6-week-old SPF healthy male SD rats(200±20 g)were selected as experimental animals and provided by Animal Experimental Center of Southwest Medical University(license number:SYXK(Chuan)2013-181).

M ain experimental reagents

Liquid preparation.Fuzi decoction:Fuzi(Aconiti Lateralis Radix Praeparata)20 g was formulated as 0.10 g/m L;Wind dispelling medicine(No.1):Fangfeng(Saposhnikoviae Radix)10 g and Baizhi(Angelicae dahuricae Radix)10 g,were formulated as 0.18 g/m L;TGD(No.2):Tianma(Gastrodiae Rhizoma)10 g,Gouteng(Uncariae Ramulus Cum Uncis)15g,Shijuem ing(Haliotidis Concha)20 g,Niuxi(Achyranthis Bidentatae Radix)10 g,and Sangjisheng(Taxilli Herba)9 g,were formulated as 0.576 g/m L.Wind dispelling medicine combined with TGD(No.3),were formulated as 0.756 g/m L.

M ajor drugs and reagents.Captopril tablets(Harbin Pharmaceutical Group),NO nitrate reductase kit(Nanjing Jiancheng biological),ET,TXB2 and 6-K-PGF1a ELISA Kit(Beijing Chenglin Biology).

Establishment of the renal hypertension model

100 SD rats were fed adaptively for 3 days.Basal blood pressure of all rats were measured using a noninvasive blood pressure measurement system(5-10 times for each measurement,and take an average).A fter fasting and water-deprivation for 24 hours,12 rats were selected to serve as the normal group(blank control group),and the remaining 88 rats(12 in the sham-operated group and 76 in the operated group)were served as the experimental group(including the operated group and the sham-operated group)by computer random ly.The surgery group was established according to the literature[9-12]by ligaturing the left renal artery to establish renal hypertensive rat model.Blood pressure of all rats was measured again 2 weeks after surgery.According to the domestic research standards and foreign hypertensive rat standards[13,14],a successful hypertensive rat model is the postoperative systolic blood pressure higher than 20 mmHg before surgery and higher than 150 mmHg.Model rats were fed with Fuzi decoction for 4 weeks and irritated every other day to establish a rat model of liver-yang hyperactivity renal hypertension rat model[15,16].The modeling method in sham operated group was same as that of the surgery group,but the left renal artery was only isolated without ligation.

Grouping and adm inistration

After establishing the model successfully,10 rats in the normal group and in sham-operated group were given 10 mL/(kg•d)normal saline respectively.50 rats in the operated group were random ly divided into model group,wind dispelling medicine group,captopril group,TGD group,and combination group(wind dispelling medicine+TGD group)of 10 rats respectively,and were given normal saline,No.1,captopril,No.2,No.3(both 10 mL/(kg•d))by gavage.Adm inistered doses were calculated according to the converting of the body surface area of human and animal[17].No.1,Captopril,No.2,No.3 by gavage were equivalent to the original drug 1.8,3.31,5.76,7.56g/(kg•d).After the model was established,the rats were administered by gavage for 4 weeks at fixed time per day,and the dosage was adjusted according to the body weight.

Preparation of serum sam p le

The blood pressure of the rats were measured 1 h after the last adm inistration,and the blood serum of the abdominal aorta blood was collected by centrifugation and centrifuged at-70°C for storage.

Test indicators

General and behavioral observation.Spirit,diet,coat color,temperament,rotation time were observed.

Serum NO detection:chem ical colorimetry.Take out frozen serum NO and leave it to thaw at room temperature.Refer to the instructions of NO nitrate reductase reagent kit to prepare the reagent,and then carry the sample operation.The specific sample operation steps are as follows(Table 1).

Table 1 Adding sam p le program of NO detection(m L)

After thoroughly mixing again at room temperature for 10 minutes,double distilled water is zeroed,the wave length of 550 nm and the optical path of 0.5 cm are selected,and the absorbance value(OD value)of each test tube is measured.

Calculation formula:NO content(μmol/L)=(OD value of test tube-OD value of control tube)/(OD value of test tube-OD value of blank tube)×standard concentration(100 μmol/L)×dilution ratio before sample testing.

Serum ET,TXB2,6-K-PGF1a detection:Use ELISA.Specific steps are as follows:(1)Frozen serum sample processing:take out the frozen serum to be measured,make it thaw at room temperature slowly;(2)carry out the experiment in accordance with the experimental steps of each detection index:①Take out the microtiter plates,followed by preparing 37.5,75,150,300,600 pg/m L standard.②Number the samples,blank wells were without samples,biotin-labeled anti-ET antibody/anti-TXB2 antibody/6-K-PGF1a antibody and streptavidin-HRP,only add chromogenic agent A&B and stop solution.③Add50μL of standard and streptavidin-HRP to the standard wells,and then add 40 μL of sample,10 μL of anti-ET antibody/anti-TXB2 antibody/6-K-PGF1a antibody and50μL of streptavidin-HRP.④Cover the microplate sealers,m ix the well and incubate it at 37°C for 1 h.⑤Open the microplate sealers,fill each hole with washing liquid,discard the liquid after 30 s,repeat this for 5 times,and pat it dry. ⑥each hole followed by dropping 50 μL of reagent A,B liquid,m ix them,avoid light at 37°C and color for 10 min.⑦each hole was followed by dropping 50 μL stop solution to term inate the reaction. ⑧set the blank hole to zero within 10 min,wavelength at 450 nm,followed by measuring the absorbance of each well(OD value).⑨calculate the standard linear regression equation,and then use this equation and the OD value of the sample to calculate the concentration of the sample.

Statistical methods

IBM SPSS22.0 software was used for statistical analysis,measurement data was shown as mean±standard deviation(X±S),and one-way ANOVA was used to determine the difference between groups.LSD test was employed to analyze the significance of the two single-agent groups.P＜0.05 was statistically significant.

Results

The establishment of model

By incomplete ligation of the left renal artery and adm inistration of Fuzi decoction,a hypertensive rat model with liver-yang hyperactivity was successfully established(53 was successful,18 was unsuccessful and 5 was dead).During the experiment,the rats in both normal group and sham-operated group had clean and glossy coat color,normal water intake,sweet-temper,physical agility.The rotation time in the both groups was not shortened.In the model group,the coat color turned yellow and tarnished,the state was sluggish,tired and lying,the amount of water intake was increased,had slow response,and the rotation time was shortened.After the rats were given with Fuzi decoction,they appeared irritable,and even bit each other.In the late treatment period,the mental status of the rats in each drug group became better,coat color became glossy,temper got much gentle,and water intake and biting phenomenon decreased.

Effect of drugs on blood pressure in hypertensive rats with liver-yang hyperactivity

The basal blood pressure in rats.The blood pressure in normal group,sham-operated group,model group,captopril group,wind dispelling medicine group,TGD group and the combination group were no significantly different.

The blood pressure of rats 2 weeks after surgery.There was no significant difference between the sham-operated group and the normal group.The systolic blood pressure of the model group was significantly higher than that of the sham-operated group and exceeded the baseline blood pressure of 20mmHg,and exceeded 150mmHg(P＜0.05).There was no significant difference among model group,captopril group,wind dispelling medicine group,TGD group and the combination group.According to the judgment criterion of rat model of renal hypertension,it indicated that renal hypertension models in each group were successfully established in each group.

Rat blood pressure 6weeks after surgery.No significant difference between the sham-operated group and the normal group;blood pressure 6 weeks after surgery in the model group was significantly higher than the sham-operated group(P＜0.05).There was no significant difference among model group,captopril group,wind dispelling medicine group,TGD group and the combination group.On the basis of the general situation and behavioral changes of rats,renal hypertensive rat models with liver-yang hyperactivity in the model group and other drug groups were successfully established.

Rat blood pressure after 4 weeks of treatment.There was no significant difference between sham-operated group and the normal group;blood pressure in the model group was significantly higher than that in the sham-operated group(P＜0.05);compared with the model group,that in the wind dispelling medicine group was not significantly reduced(P＞0.05),and blood pressure in captopril group,TGD group and the combination group were significantly lower than sham-operated group(P＜0.05);blood pressure in Captopril group is significant higher than that in the sham-operated group(P＜0.05).Compared with the Captopril group,blood pressure in wind dispelling medicine group was significantly higher(P＜0.05),but TGD group was not(P＞0.05),and the combination group was significantly lower(P＜0.05).Compared with wind dispelling medicine group,the TGD group and the combination group were both significantly lower(P＜0.05).(Table 2)

Table 2 Changes of systolic blood pressure in rats before and after treatment(¯±S)

Table 2 Changes of systolic blood pressure in rats before and after treatment(¯±S)

▲P＜0.05 vs Sham-operated group,★P＜0.05 vs Model group,◆P＜0.05 vs Captopril group,■P＜0.05 vs wind dispelling medicine group;▼P＜0.05 vs Tianma gouteng Decoction I group;Combination group(wind dispelling medicine group+Tianma gouteng Decoction I group)

ps Cases Basic blood Blood pressure 2Blood pressure 6Blood pressure Grou pressure(mmHg)after treatment for 4 weeks(mmHg)Normal group10105.00±3.08108.00±3.52109.00±2.02107.00±2.47 Sham-operated group weeks after surgery(mmHg)weeks after surgery(mmHg)10106.00±3.05110.00±4.24108.00±4.72108.00±2.47 Model group10106.00±3.78154.00±3.40▲158.00±5.27▲152.00±2.73▲Captopril group10105.00±4.47155.00±3.00▲158.00±5.05▲140.00±3.11★Wind dispelling medicine group 10107.00±5.04154.00±2.10▲161.00±4.81▲151.00±1.77◆Tianma Gouteng Decoction I group 10106.00±4.13155.00±3.00▲160.00±4.33▲138.00±3.24★■Combination group10105.00±3.54154.00±2.50▲162.00±4.29▲131.00±3.38★◆■▼F value0.73490.46316.62457.74

Effects of drugs on vasoactive substances in serum of renal hypertensive rats with liver-yang hyperactivity

Serum ET and TXB2.There was no significant difference between the sham-operated group and the normal group;Serum ET and TXB2 in the model group was significantly higher than that of the sham-operated group(P＜0.05);Compared with the model group,Serum ET and TXB2 in the wind dispelling medicine group did not decrease significantly,and those in the Captopril group,TGD group and the combination group were significantly decrease(P＜0.05);Serum ET and TXB2 in Captopril group was much higher than those in the sham-operated group(P＜0.05);Compared with captopril group,Serum ET and TXB2 in wind dispelling medicine group has significant increase(P＜0.05)and there was no significant difference with those in TGD(P＜0.05).Compared with wind dispelling medicine group,Serum ET and TXB2 in the combination of TGD group and combination group decreased significantly(P＜0.05).Compared with TGD group,Serum ET and TXB2 in the combination group was significantly lower(P＜0.05).(Table 3)

Table 3 Changes of ET,TXB2 in groups of rats(¯±S)

Table 3 Changes of ET,TXB2 in groups of rats(¯±S)

▲P＜0.05 vs Sham-operated group,★P＜0.05 vs Model group,◆P＜0.05 vs Captopril group,■P＜0.05 vs wind dispelling medicine group;▼P＜0.05 vs Tianma Gouteng Decoction I group;Combination group(wind dispelling medicine group+Tianma Gouteng Decoction I group)

Groups Cases ET(pg/m L)TXB2(pg/m L)Normal group1093.81±2.1899.72±1.98 Sham-operated group1093.45±2.4999.95±2.10 Model group10154.30±3.48▲154.12±3.21▲Captopril group10117.80±2.10★120.48±2.79★Wind dispelling medicine group 10117.40±2.08★■121.45±3.12★■Combination group10105.24±3.04★◆■▼106.95±2.18★◆■▼F value945.86717.49 10152.85±2.60◆152.80±3.12◆Tianma Gouteng Decoction I group

Serum NO and 6-K-PGF1a.There was no significant difference between the sham-operated group and the normal group,the model group decreased significantly than the sham-operated group(P＜0.05).Compared with the model group,serum NO and 6-K-PGF1a in the wind dispelling medicine group did not increase obviously(P＞0.05),and those in Captopril group,TGD group,and combination group increased obviously(P＜0.05),serum NO and 6-K-PGF1a in Captopril group was much higher than sham-operated group(P＜0.05);Compared with Captopril group,wind dispelling medicine group decreased significantly,the combination group increased markedly(P＜0.05),and no significant difference was found between TGD group and Captopril group.Compared with the wind dispelling medicine group,TGD group and combination group increased significantly(P＜0.05).Compared with TGD group,the combination group was much higher(P＜0.05)(Table 4).

Table 4 Changes of NO,6-K-PGF1a in groups of rats(±S)

Table 4 Changes of NO,6-K-PGF1a in groups of rats(±S)

▲P＜0.05 vs Sham-operated group,★P＜0.05 vs Model group,◆P＜0.05 vs Captopril group,■P＜0.05 vs wind dispelling medicine group;▼P＜0.05 vs Tianma gouteng Decoction I group;Combination group(wind dispelling medicine group+Tianma gouteng Decoction I group)

Groups Cases NO(µmol/m L)6-K-PGF1a(pg/m L)Normal group1031.73±1.7945.72±2.79 Sham-operated group1031.22±1.4345.86±2.41 Model group1023.05±2.10▲30.75±2.66▲Captopril group1050.24±2.53★65.61±2.99★Wind dispelling medicine group 1050.03±2.55★■64.35±3.22★■Combination group1059.90±1.88★◆■▼85.33±3.42★◆■▼F value441.55487.05 1024.64±2.67◆32.94±2.06◆Tianma Gouteng Decotion I group

Discussion

In traditional Chinese medicine(TCM),hypertension belongs to “headache”,“dizziness”,“stroke”etc.,and the lesions locate in the brain.The pathogenesis is associated with wind,fire,phlegm,stasis,and weakness.The TCM syndrome types of primary hypertension are diverse,and the syndrome of liver-yang hyperactivity is most common in clinic.This syndrome is mainly treated by calm ing liver to stop endogenous wind,and activating blood and clearing heat.Tianma Gouteng Decoction is derived from book Zabingzhengxinyi by Hu GuangCi,with the effect of calm ing liver and suppressing yang.In recent years,many clinical studies have shown that Tianma Gouteng Decoction has a good antihypertensive effect[18-30].Orthogonal test results showed that orthogonal 1 party(TGD)was confirmed to increase the antihypertensive effect[6].TGD consisted of Tianma(Gastrodiae Rhizoma),Gouteng(Uncariae Ramulus Cum Uncis),Shijueming(Haliotidis Concha),Niuxi(Achyranthis Bidentatae Radix),Sangjisheng(Taxilli Herba).Sovereign drugs include Tianma(Gastrodiae Rhizoma)and Gouteng(Uncariae Ramulus Cum Uncis),exerting the effect of calming liver to stop endogenous wind.Shijueming(Haliotidis Concha)can calm the liver,suppress yang and clear heat.Meanwhile,it can be coordinated with the sovereign drugs to calm liver and stop endogenous wind;Niuxi(Achyranthis Bidentatae Radix)can ensure proper downward flow of the blood,activate blood and promote diuresis,tonify the liver and kidney to nourish Yin,and downbear fire and suppress yang;Sangjisheng(Taxilli Herba)can tonify the liver and kidney.A reasonable compatibility of these herbs can calm liver and stop endogenous wind,clear heat and active blood,and tonify the liver and kidney.

“Wind med ic ine”firstly o rig inated from the Yixueqiyuan published in Jin Dynasty(A.D.1115-A.D.1234)by Zhang YuanSu.“Analogizing Chinese medicines with natural phenomenon”was firstly initiated by Zhang,it takes the five evolutive phases from the world as the law,indicating that“The herbs have the thickness of sm ell,the property of the ascendingdescending-floating-sinking,the method of reinforcing and reducing,and are different from each other”.Herbs commonly used were summarized as“wind,ascend and generate”,“heat,flo tation and grow th”,“w et,transformation,complete”,“dry,descend,and reapness”,“cold,sink,and storage”.Among them,“wind,ascend an d gene ra te”ca teg o ry con tain s Fang feng(Saposhnikov iae Radix),Qianghuo(No top terygh Rhizoma Et Radix),Shengma(Cim icifugae Rhizoma),Chaihu(Bup leuri Radix),Gegen(Puerariae Lobatae Radix),Weilingxian(Clematidis Radix Et Rhizoma),Xixin(Asari Radix Et Rhizoma),Duhuo(Angelicae Pubescentis Radix),Baizhi(Angelicae dahuricae Radix),Niubangzi(Arctii Fructus),Jiegeng(Platycodonis Radix),Gaoben(Ligustici Rhizom a Et Radix),Chuanxiong(Chuanxiong Rhizoma),M anjingzi(Viticis Fructus),Qin jiao(Gen tianae Macrophy llae Radix),Tianm a(Gastrodiae Rhizom a),M ahuang(Ephed rae Herba),Jing jie(Sch izonepetae Herba),Bohe(M en thae Hap localycis Herba),Qianhu(Peucedani Radix)and other 20 herbs,described as the origin of wind dispelling medicine at later ages[31,32].In modern times,most of the wind dispelling medicine refer to a class of drugs that have the effect of expelling wind and dispersing evil[33,34].They are good at regulating functional activities and directing d rugs.They are mostly used for treating diseases caused by wind-evil in clinic.Suwen-Zhizhenyaodalun records that:“The pathogenesis of all the wind-induced symptoms is due to the liver”,and dizziness means “no wind,no dizziness”.Lin Ping-Qing pointed out that the use of expelling wind medicine was not lim ited to expelling wind,but also extinguishing wind,which is the main function of wind expelling medicine.Zhang Jing-Yue said “no weakness,no dizziness”.The wind dispelling medicine can act as a synergist of tonic medicine.On the basis of Wei Yu-Huang’s all-along decoction,Shengma(Cim icifugae Rhizoma)and Niuxi(A chy ran this Biden tatae Radix)w ere added with excellent effect.Dizziness has the statement that“no stasis,no dizziness”,the wind dispelling medicine can promote circulation and remove stasis indirectly or directly,as“Medications made from flying insects have a rising effect.M edications made from crawling insects have a declining effect.When the blood flowis not blocked,the flow of Qi will be unobstructed”,Zhu Dan-Xi said:“no phlegm,no dizziness”,wind dispelling med ic ine can elim inate dam pness and ph legm.

Fangfeng(Saposhnikoviae Radix)was first recorded in the Shennongbencaojing as spicy,sweet,and mild in nature.Bencaogangmu recorded:“Among the thirty-six kinds of wind,Fangfeng(Saposhnikoviae Radix)can remove wind and evil in upper-jiao,ease smolder of head and eyes,expel dampness in meridians,and relieve joint pain.It’s a dispelling wind and elim inating dampness drug.Yaoleifaxiang records that it is in common use to cure wind-induced disease,reduce the lung excess,disperse smolder of head and eyes,and remove wind and evil in upper-jiao.The dispersing smolder of head and eyes of Fangfeng(Saposhnikoviae Radix)is accordance with the disease lesion of hypertension is in brain.Stagnation of qi will block the circulation of blood,and finally cause blood stasis after a long time.Losing the warm effect can cause phlegm coagulation,and a long time of qi stagnation will lead to fire formation and heat formation.Besides,the aspect of treating wind is accordance with“wind,heat,phlegm,stasis” of hypertension.In addition,three kinds of lactones in Saposhnikoviae Radix(macrocyclic diterpenoids in traditional Chinese medicine Fangfeng(Saposhnikoviae Radix))had obvious antihypertensive effect on anesthetic dogs[35].Fangfengtongsheng pills(Mangxiao(Natrii Sulfas)，Dahuang(Rhei Radix Et Rhizoma)，Gancao(Glycyrrhizae Radix Et Rhizoma),Fangfeng(Saposhnikoviae Radix))could decrease the artery pressure of rabbits,with the mechanism of active Mreceptor on blood vessel.Fangfeng(Saposhnikoviae Radix)can treat “tinnitus”, “dizziness”,and other hypertensive disease[37].Baizhi(Angelicae dahuricae Radix)was firstly recorded in Shennongbencaojing,and is spicy in flavor and warm in nature.Bencaoqiuzhen records that Baizhi(Angelicae dahuricae Radix)has strong effect,can open the apertures and relieve exterior syndrome,as the main herb exerting the effect of dispelling wind and dissipating wet of the Stomach Meridian of Foot-yangm ing.So it can treat all disease of yangm ing.Bencaogangmu records that“Baizhi(Angelicae dahuricae Radix),white in color and spicy in flavor,warm in nature and thick of smell,effects at hand-yangm ing.Aroma ascends and goes into the Lung Meridian of Hand-Taiyin,treating head,eyes,eyebrow,teeth,and other disease,which is accordance with the lesion location in brain in hypertension.Bencaogangmu records that:“Baizhi(Angelicae dahuricae Radix)is the main herb of yangm ing,so it can cure blood disease.”Bencaozhengyi records that:“Baizhi(Angelicae dahuricae Radix),spicy and warm and especially fragrant,can dry wetness of the body.Benjing records that it makes skin grow th and skin color moist by the effect of raising and warm ing Qi.It does not mean that it can treat all ulcers,and speed up muscle building.Damingbencao said it could remove stale blood,produce new blood,discharge pus and relieve pain,used for acute mastitis,lumbodorsal carbuncle,crewels,anal fistula,trauma,acariasis. “Dry wet”, “treat blood disease”, “warm Qi”,“remove stale blood”,all are accordance with “phlegm,stasis,deficiency”in hypertension.In addition,Zhaohongwan,et al[38-40]demonstrated that Baichuan capsules had obvious antihypertensive effect.Baichuan capsules can alleviate the property of hemorheology and microcirculation disturbance,and suppress extrinsic blood coagulation system,so it has the effects of promoting circulation and removing stasis.Lubai capsules(Lugen(Phragm itis Rhizoma),Baishao(Paeoniae Radix Alba),Fangfeng(Saposhnikoviae Radix),Jingjiehui(Schizonepetae Spica))can alleviate the property of hemorheology and microcirculation disturbance,and suppress extrinsic blood coagulation system,so it has the effect of promoting circulation and removing stasis[41].From aspect of the five flavors,Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix)belong to pungent.Neijing firstly summarizes the representative herbs of five flavors,and regards pungent has the effect of dispersing,pungent,could diffuse and promote Qi,which could relieve the exterior and elim inating pathogens from exterior and promote the circulation of Qi and blood,which is accordance with the pathogenesis of hypertension“wind,phlegm,stasis”.Wind drug can enhance the effect of promoting circulation and removing stasis[31].In the present study,we choose Fangfeng(Saposhnikoviae Radix),and Baizhi(Angelicae dahuricae Radix)to enhance the effect of Tianma Gouteng Decoction I by dispelling wind,clearing heat,invigorating the circulation of blood,and promoting the falling of blood pressure.The experiment revealed that Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix),expelling pathogenic wind,calming endogenous wind,relieving the exterior and elim inating pathogens from exterior,promoting circulation and removing stasis,kept the circulation function normally and lowered the blood pressure.So,Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix)have synergistic effect with TGD on reducing blood pressure.

Currently vascular endothelial injury was regarded as the main factor of vascular remodeling and hypertension.Vascular endothelial cells can secrete anti-atherosclerotic and atharosclerosis substances.The former includes NO and 6-K-PGF1a,with the effects of anticoagulation,vascular dilation effects;the latter includes ET and TXB2,with procoagulant and vasodilative effects[42].The two types of substances interact with each other to maintain homeostasis,and regulate the vasomotor function together.The experimental results showed that Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix)could enhance the effect of Tianma Gouteng Decoction I by maintaining the dynam ic balance of vasoactive substances.Combining the experiment results and modern pharmacological studies[43-46],we found that Fangfeng(Saposhnikoviae Radix)and Baizhi(Angelicae dahuricae Radix)[43-46]were likely to regulate the level of vasoconstrictor substances in vivo,inhibit platelet aggregation,regulate the stability and liquidity of blood circulation,protect vascular endothelial cells,and lower blood pressure.