陳亞峰 奉典旭 陳騰 田繼云 謝金昆 施浩然 張靜喆 韓峰
·論著·
大承氣湯對(duì)急性壞死性胰腺炎大鼠胰腺水通道蛋白1的影響
陳亞峰 奉典旭 陳騰 田繼云 謝金昆 施浩然 張靜喆 韓峰
目的觀察急性壞死性胰腺炎(ANP)大鼠胰腺組織水通道蛋白1(AQP1)的表達(dá)以及大承氣湯對(duì)其的影響。方法160只雄性SD大鼠按隨機(jī)數(shù)字法分為對(duì)照組、ANP組、地塞米松組、乙酰唑胺組及大承氣湯組,每組32只。采用膽胰管逆行注射5%?;悄懰徕c方法制備ANP模型。地塞米松組于造模后即刻靜脈給予地塞米松4 mg/kg體重;乙酰唑胺組于造模前2 h用含乙酰唑胺的生理鹽水1 ml灌胃;大承氣湯組于造模前48、24、2 h分別用大承氣湯2 ml/次灌胃;對(duì)照組僅開腹觸摸胰腺數(shù)次后關(guān)腹。制模后3、6、12、18 h分批處死8只大鼠。記錄腹水量;檢測(cè)血清淀粉酶;胰腺組織病理檢查及電鏡觀察;伊文思蘭(EB)血管外滲法檢測(cè)毛細(xì)血管通透性;實(shí)時(shí)PCR和蛋白質(zhì)印跡法檢測(cè)AQP1 mRNA和蛋白表達(dá)。結(jié)果ANP組血清淀粉酶水平顯著升高,胰腺損傷明顯;地塞米松組和大承氣湯組淀粉酶水平較ANP組降低,胰腺損傷減輕;乙酰唑胺組淀粉酶水平高于ANP組,胰腺病理?yè)p傷較ANP組加重。造模后6 h,對(duì)照組、ANP組、地塞米松組、乙酰唑胺組、大承氣湯組胰腺組織EB含量分別為(13.44±2.56)、(126.35±14.80)、(86.31±14.46)、(108.99±15.07)、(78.29±16.85)mg/L;AQP1 mRNA表達(dá)量為(170.07±22.48)%、(83.93±8.98)%、(117.09±10.70)%、(69.00±8.98)%、(112.82±11.79)%;AQP1蛋白表達(dá)量為0.23±0.06、0.10±0.02、0.32±0.03、0.13±0.02、0.45±0.04。ANP組的EB量顯著高于對(duì)照組,而AQP1 mRNA及蛋白的表達(dá)顯著低于對(duì)照組(P值均<0.05);地塞米松組及大承氣湯組EB含量顯著低于ANP組,而AQP1 mRNA及蛋白的表達(dá)顯著高于ANP組(P值均<0.05)。結(jié)論AQP1在ANP大鼠胰腺組織毛細(xì)血管滲漏的發(fā)生中起重要作用。大承氣湯通過調(diào)控AQP1的表達(dá)可減輕ANP大鼠的胰腺損傷。
急性胰腺炎,壞死性; 大承氣湯; 水通道蛋白1; 毛細(xì)血管內(nèi)皮屏障
毛細(xì)血管內(nèi)皮屏障功能損害是重癥急性胰腺炎(SAP)發(fā)病早期重要的病理生理變化[1]。目前研究表明,經(jīng)內(nèi)皮細(xì)胞介導(dǎo)的水轉(zhuǎn)運(yùn)障礙是SAP時(shí)毛細(xì)血管通透性升高的重要環(huán)節(jié)。水通道蛋白(aquaporins,AQPs)是一組構(gòu)成水通道并與水通透有關(guān)的細(xì)胞膜轉(zhuǎn)運(yùn)蛋白,其中水通道蛋白1(AQP1)廣泛分布于機(jī)體的毛細(xì)血管內(nèi)皮,選擇性介導(dǎo)細(xì)胞膜內(nèi)外水的轉(zhuǎn)運(yùn)。糖皮質(zhì)激素可上調(diào)AQP1表達(dá)[2-3],而乙酰唑胺則可抑制其表達(dá)[4]。大承氣湯在臨床上用于治療急性胰腺炎,療效顯著。本研究觀察大承氣湯對(duì)急性壞死性胰腺炎(ANP)大鼠胰腺AQP1表達(dá)及毛細(xì)血管內(nèi)皮屏障功能的影響。
一、動(dòng)物模型制備
清潔級(jí)雄性SD大鼠160只,體重(220±30)g,購(gòu)自上海西普爾-必凱實(shí)驗(yàn)動(dòng)物有限公司,生產(chǎn)許可證為SCXK(滬)2003-0002。按數(shù)字表法隨機(jī)分為對(duì)照組、ANP組、地塞米松組、乙酰唑胺組及大承氣湯組,各32只。采用膽胰管逆行注射5%?;悄懰徕c(Sigma公司)1.5 ml/kg體重的方法制備ANP模型。地塞米松組于造模后即刻經(jīng)陰莖靜脈給予地塞米松4 mg/kg體重[5];乙酰唑胺組于造模前2 h給予乙酰唑胺56 mg/kg體重[6](生理鹽水稀釋)灌胃;大承氣湯組于制模前48、24、2 h分別用大承氣湯(大黃12 g、厚樸24 g、枳實(shí)12 g、芒硝6 g)[7]2 ml灌胃[8]。造模后3、6、12、18 h分批處死8只大鼠。處死前1 h經(jīng)陰莖靜脈注入2%伊文思蘭(EB,Sigma公司)1 ml/kg體重。記錄腹水量;抽取血樣本;取胰腺組織,部分置2.5%戊二醛溶液中固定,部分甲醛固定,部分液氮凍存。
二、檢測(cè)項(xiàng)目及方法
1.血清淀粉酶測(cè)定:采用酶法在全自動(dòng)生化分析儀上測(cè)定。
2.胰腺組織病理學(xué)檢查:由病理科醫(yī)師盲法閱片,并根據(jù)Schmidt標(biāo)準(zhǔn)[9]進(jìn)行病理學(xué)評(píng)分。
3.毛細(xì)血管通透性測(cè)定:取胰腺組織300 mg,加入1 ml甲酰胺溶液,60℃孵育24 h。2000 r/m離心30 min,取上清液。采用紫外分光光度計(jì)法測(cè)定620 nm處吸光值(A),以空白管調(diào)零。根據(jù)已知EB濃度繪制標(biāo)準(zhǔn)曲線。根據(jù)所測(cè)組織的A620值計(jì)算組織中EB含量。
4.胰腺組織超微結(jié)構(gòu)檢查:取2.5%戊二醛固定的胰腺組織,經(jīng)1%鋨酸后固定、脫水、滲透包埋、切片、電子染色,于透射電鏡下觀察超微結(jié)構(gòu)變化。
5.AQP1 mRNA表達(dá)檢測(cè):取凍存的胰腺組織,Trizol(Invitrogen公司)法抽提總RNA。先逆轉(zhuǎn)錄為cDNA,再行實(shí)時(shí)熒光定量PCR。AQP1正義序列5′-CTCCGGGCTGTCATGTATATCA-3′,反義序列5′-ATGGCGGAGGCAACGA-3′,探針5′-CGCCCAGTG-TGTGGGAGCC-3′;內(nèi)參DAPDH正義序列5′-CCGAGGGCCCACTAAAGG-3′,反義序列5′-GCTGTT-GAAGTCACAGGAGACAA-3′, 探針5′-CATCCTGGG-CTACACTGAGGACCA-3′。PCR反應(yīng)條件: 95℃ 2 min,95℃ 30 s、58℃ 30 s,40次循環(huán)。每個(gè)樣本測(cè)2次。應(yīng)用儀器自帶軟件獲取Ct值。mRNA相對(duì)定量通過2-△Ct×100%計(jì)算,△Ct值= Ct值A(chǔ)QP1-Ct值GAPDH。
6.AQP1蛋白檢測(cè):凍存的胰腺組織經(jīng)裂解后制成勻漿,采用BCA試劑盒測(cè)定蛋白濃度后常規(guī)行蛋白質(zhì)印跡法,以β-actin作為內(nèi)參。用ImageJ(1.33h, National Institutes of Health)分析軟件獲取條帶的灰度值,以AQP1與β-actin的灰度比值表示蛋白相對(duì)表達(dá)量。
三、統(tǒng)計(jì)學(xué)處理
一、腹水量
對(duì)照組大鼠無(wú)腹水形成;ANP組可見淡黃色或紅色血性腹水,制模后12 h腹水量最多;乙酰唑胺組腹水量較ANP組多;地塞米松組及大承氣湯組腹水量明顯少于ANP組(P<0.01,表1)。
二、胰腺組織病理學(xué)改變
對(duì)照組胰腺未見明顯異常;ANP組胰腺水腫、出血、壞死,有炎性細(xì)胞浸潤(rùn);乙酰唑胺組胰腺組織病理改變較ANP組稍有加重,但差異無(wú)統(tǒng)計(jì)學(xué)意義;地塞米松組及大承氣湯組胰腺組織病變較ANP組明顯減輕(P<0.05,表1,圖1)。
三、血清淀粉酶水平
ANP組血清淀粉酶水平顯著高于對(duì)照組;地塞米松組及大承氣湯組各時(shí)間點(diǎn)淀粉酶水平均低于同時(shí)點(diǎn)ANP組(P值均<0.05);乙酰唑胺組血清淀粉酶水平較ANP組高,但差異并無(wú)統(tǒng)計(jì)學(xué)意義(表2)。
四、胰腺組織毛細(xì)血管超微結(jié)構(gòu)改變
對(duì)照組胰腺組織毛細(xì)血管結(jié)構(gòu)完整,管壁連接完整,內(nèi)容物清晰,紅細(xì)胞形狀規(guī)整,管周組織正常,細(xì)胞內(nèi)細(xì)胞器完整;ANP組毛細(xì)血管管壁變薄,內(nèi)皮細(xì)胞間連接復(fù)合體被破壞,管內(nèi)紅細(xì)胞大量聚集,結(jié)構(gòu)不完整;乙酰唑胺組毛細(xì)血管結(jié)構(gòu)破壞較ANP組嚴(yán)重;地塞米松組及大承氣湯組較ANP組減輕(圖2)。
五、胰腺組織毛細(xì)血管通透性改變
ANP組胰腺組織毛細(xì)血管通透性從3 h起較對(duì)照組顯著增加;乙酰唑胺組僅3 h點(diǎn)的毛細(xì)血管通透性較ANP組顯著增加;地塞米松組及大承氣湯組從6 h起血管通透性均較ANP組顯著降低(P值均<0.05,表3)。
六、胰腺組織AQP1 mRNA和蛋白表達(dá)
ANP組大鼠胰腺組織AQP1 mRNA和蛋白表達(dá)從3 h起明顯低于對(duì)照組;乙酰唑胺組的表達(dá)顯著低于ANP組;地塞米松組及大承氣湯組的表達(dá)顯著高于ANP組(P值均<0.05,表4,圖3)。
表1 各組大鼠腹水量、胰腺病理評(píng)分的變化
注:a指各組每個(gè)時(shí)點(diǎn)的只數(shù);與ANP組比較,bP<0.05
圖1 對(duì)照組(a)、ANP組(b)、乙酰唑胺組(c)、地塞米松組(d)、大承氣湯組(e)的胰腺病理改變(HE ×200)
表2 各組大鼠血清淀粉酶水平的變化
注:a指各組每個(gè)時(shí)點(diǎn)的只數(shù);與對(duì)照組比較,bP<0.05;與ANP組比較,cP<0.05
圖2 對(duì)照組(a)、ANP組(b)、乙酰唑胺組(c)、地塞米松組(d)、大承氣湯組(e)胰腺毛細(xì)血管的超微結(jié)構(gòu)變化( ×8200)
表3 各組胰腺組織毛細(xì)血管通透性比較
注:a指各組每個(gè)時(shí)點(diǎn)的只數(shù);與對(duì)照組比較,bP<0.05;與ANP組比較,cP<0.05
表4 各組胰腺組織AQP1 mRNA和蛋白表達(dá)的變化
注:a指各組每個(gè)時(shí)點(diǎn)的只數(shù);與對(duì)照組比較,bP<0.05;與ANP組比較,cP<0.05
圖3對(duì)照組(1)、ANP組(2)、乙酰唑胺組(3)、地塞米松組(4)、大承氣湯組(5)胰腺組織AQP1蛋白表達(dá)
毛細(xì)血管內(nèi)皮屏障功能損害是SAP發(fā)病的關(guān)鍵環(huán)節(jié)。多種因素?fù)p傷毛細(xì)血管內(nèi)皮,引起血管通透性升高,局部的炎癥介質(zhì)通過高通透性的微血管進(jìn)入血液,造成全身性炎癥反應(yīng),同時(shí)血管內(nèi)液外滲到組織間隙,造成廣泛的水腫及血液循環(huán)障礙,進(jìn)一步加重病情。水通道蛋白AQP1參與急性胰腺炎的發(fā)病過程。Ohta等[10]研究發(fā)現(xiàn),AQP1敲除小鼠對(duì)雨蛙素誘導(dǎo)的水腫性胰腺炎易感性升高。Ko等[11]研究也發(fā)現(xiàn),自身免疫性胰腺炎患者的胰管質(zhì)膜的AQP1表達(dá)上調(diào)。高振明等[12]研究表明,AQP1參與急性胰腺炎相關(guān)肺損傷的形成。
本實(shí)驗(yàn)結(jié)果顯示,造模后3 h起,ANP組血清淀粉酶顯著升高,出現(xiàn)明顯的腹水,胰腺組織EB含量顯著增加,AQP1 mRNA和蛋白的表達(dá)顯著下降,表明在ANP大鼠模型早期,由于AQP1表達(dá)下降引起胰腺組織的毛細(xì)血管通透性顯著升高。
地塞米松可上調(diào)AQP1表達(dá),而乙酰唑胺下調(diào)其表達(dá)。本實(shí)驗(yàn)分別用地塞米松和乙酰唑胺干預(yù)ANP大鼠,結(jié)果顯示,地塞米松組大鼠胰腺AQP1基因表達(dá)增加,胰腺病理?yè)p傷減輕,胰腺毛細(xì)血管通透性降低,而乙酰唑胺組的表現(xiàn)與其相反,進(jìn)一步證實(shí)AQP1基因參與毛細(xì)血管通透性的調(diào)控。本實(shí)驗(yàn)又應(yīng)用大承氣湯干預(yù)ANP大鼠,結(jié)果顯示,大承氣湯與地塞米松干預(yù)的效果一致。它們?cè)谡{(diào)控AQP 1基因表達(dá)、減輕胰腺病理?yè)p傷、降低胰腺組織毛細(xì)血管通透性等方面的效應(yīng)無(wú)顯著差異,而在減少腹水量及降低血清淀粉酶水平方面,大承氣湯較地塞米松更顯著。
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EffectofDachengqidecoctiononpancreasaquaporin1inratswithacutenecrotizingpancreatitis
CHENYa-feng,FENGDian-xu,CHENTeng,TIANJi-yun,XIEJin-kun,SHIHao-ran,ZHANGJing-zhe,HANFeng.
DepartmentofGeneralSurgery,PutuoHospital,ShanghaiUniversityofTraditionalChineseMedicine,Shanghai200062,China
FENGDian-xu,Email:fdianxu@sohu.com
ObjectiveTo detect the expression of aquaporin 1 in pancreas of rats with acute necrotizing pancreatitis (ANP) and to study the effect of Dachengqi decoction on it.MethodsOne hundred and sixty male SD rats were randomly divided into control group (C group,n=32), ANP group (n=32), Dexamethasone group (De group,n=32), Acetazolamide group (A group,n=32) and Dachengqi decoction group (DD group,n=32). ANP model was induced by retrograde injection of 5% sodium taurocholate into the biliary and pancreatic duct. Rats in De group
dexamethasone (4 mg/kg) intravenously after ANP induction; while rats in A group received 1 ml acetazolamide via gastric lavage 2 h before ANP induction; rats in DD group received 2 ml Dachengqi decoction via gastric lavage 48, 24, 2h before ANP induction;rats in C group received laparotomy. Eight rats in each group were sacrificed at 3 h, 6 h, 12 h and 18h after induction of ANP models. Quantity of ascites and levels of serum amylases were measured. Pathological changes in pancreas tissue were detected by HE and electron microscope. Capillary permeability in pancreas tissue was detected by Evans Blue (EB) extravasations method. AQP1 expression in pancreas tissue was detected by real-time PCR and Western blotting.ResultsLevels of serum amylase in ANP group was significantly higher, and the pancreatic injuries were obvious; the levels of serum amylase in De group and DD group was lower than that in ANP group, and the pancreatic injuries were attenuated. The levels of serum amylase in A group were higher than that in ANP group, and the pancreatic injuries were more severe than that in ANP group. Six hours after ANP induction, the levels of EB in pancreas were (13.44±2.56), (126.35±14.80), (86.31±14.46), (108.99±15.07), (78.29±16.85)mg/L In C group, ANP group, De group, A group and DD group, and the expression of AQP1 mRNA in pancreatic tissue was (170.07±22.48)%, (83.93±8.98)%, (117.09±10.70)%, (69.00±8.98)%, (112.82±11.79)%; and the expression of AQP1 protein was 0.23±0.06, 0.10±0.02, 0.32±0.03, 0.13±0.02, 0.45±0.04. The content of EB in ANP group was higher than that in C group, while the expression of AQP1 mRNA and protein in ANP group was significantly lower than that in C group (P<0.05). The content of EB in De group and DD group was significantly lower than that in ANP group, while the expression of AQP1 mRNA and protein was significantly higher than that in ANP group (P<0.05).ConclusionsAQP1 plays an important role in the pathogenesis of capillary endothelial barrier dysfunction in rats with ANP. Dachengqi Decoction can attenuate pancreatic injuries of rats by regulating the expression of AQP1.
Acute pancreatitis, necrotizing; Dachengqi decoction; Aquaporin 1; Capillary endothelial barrier
10.3760/cma.j.issn.1674-1935.2012.01.013
國(guó)家自然科學(xué)基金(30701136);上海市青年科技啟明星計(jì)劃(05QMX1450)
200062 上海,上海中醫(yī)藥大學(xué)附屬普陀醫(yī)院普外科(陳亞峰、奉典旭、陳騰、田繼云、謝金昆、施浩然、韓峰);上海中醫(yī)藥大學(xué)附屬龍華醫(yī)院普外科(張靜喆)
奉典旭,Email:fdianxu@sohu.com
2011-05-23)
(本文編輯:呂芳萍)