丹參酮ⅡA對腦缺血再灌注損傷大鼠腦組織及血清中NO含量及NO

1、丹參酮A對腦缺血再灌注損傷大鼠腦組織及血清中NO含量及NOS、iNOS活性的影響 11-05-06 15:14:00 作者：李浩,劉開祥,俸軍林編輯：studa20【摘要】 目的 觀察丹參酮A(Tan A)對腦缺血再灌注損傷大鼠腦組織及血清中一氧化氮(NO)含量、一氧化氮合酶(NOS)及誘導(dǎo)型一氧化氮合酶(iNOS)活性的影響,探討其對腦缺血再灌注損傷保護(hù)作用的可能機(jī)制。方法 將大鼠隨機(jī)分為假手術(shù)組、缺血再灌注組、Tan A低、高劑量組,線栓法建立局灶性腦缺血再灌注模型。Tan A高、低劑量組于術(shù)前連續(xù)灌胃給予高、低劑量Tan A 3 d,每日1次。各組于腦缺血90 min再灌注24 h后進(jìn)行

2、HE染色,觀察病理形態(tài)學(xué)變化,檢測腦組織和血清中NO含量和NOS、iNOS活性的變化。結(jié)果 Tan A高、低劑量組腦組織缺血損傷病理學(xué)改變明顯輕于缺血再灌注組,Tan A高劑量組缺血改變亦輕于低劑量組。與假手術(shù)組比較,缺血再灌注組腦組織和血清中NO含量和NOS、iNOS活性明顯升高；與缺血再灌注組比較,Tan A高、低劑量組腦組織和血清中NO含量和NOS、iNOS活性均明顯降低,高、低劑量組之間差異具有統(tǒng)計學(xué)意義(P0.05)。結(jié)論 Tan A可減輕神經(jīng)元損傷程度,對缺血再灌注腦損傷具有保護(hù)作用,其機(jī)制可能與降低NOS、iNOS活性,減少NO含量有關(guān)。 【關(guān)鍵詞】 缺血再灌注損傷；一氧化氮；一

3、氧化氮合酶；誘導(dǎo)型一氧化氮合酶；丹參酮A；大鼠 Abstract：Objective To study effect of Tanshinone A (Tan A) on the content of NO and the activities of NOS and iNOS in cerebral ischemia reperfusion (I/R) injury rats, and explore its protective mechanism. Methods Rats were randomly divided into 4 groups, which were sham opera

4、ted group, I/R group, low dose Tan A treated group and high dose Tan A treated group. The focal middle cerebral arterymocclusion (MCAO) model was made by suture-occluded method. Rats were pretreated with Tan A, ig for 3 d before MCAO. After 90 min MCAO following 24 h of reperfusion, pathomorphologic

5、 changes was investigated with HE staining. The content of NO and the activities of NOS and iNOS was also determined. Result The change of ischemic impairment in low or high dose Tan A treated group was lighter than that of I/R group, and high dose Tan A treated group was lighter than that of low do

6、se Tan A treated group. Compared with sham operated group, the content of NO and the activities of NOS and iNOS increased at 24 h of reperfusion in the ischemic territory (P0.05). Compared with I/R group, low and high dose Tan A treated group reduced the content of NO and the activities of NOS and i

7、NOS dose-dependently (P0.05). Conclusion Tan A has protective effect on cerebral I/R injury by reducing the content of NO and the activities of NOS and iNOS dose-dependently. Key words：ischemiareperfusion injury；NO；NOS；iNOS；Tanshinone A；rat 一氧化氮(NO)是機(jī)體內(nèi)重要的信使分子和效應(yīng)分子,為神經(jīng)傳遞、血管舒張、調(diào)節(jié)神經(jīng)功能的內(nèi)源性介質(zhì),與神經(jīng)系統(tǒng)的生理和病

8、理過程關(guān)系密切1,而一氧化氮合酶(NOS)是NO生物合成的限速酶。丹參為唇形科鼠尾草屬植物,具有活血化瘀、寧心安神等功效,目前在缺血性腦血管病的治療中廣為應(yīng)用。有研究發(fā)現(xiàn),丹參能下調(diào)缺血所致的NOS表達(dá),使NO合成減少,減輕缺血性腦損傷2。本實驗采用大鼠局灶性腦缺血再灌注模型,研究丹參酮A(Tanshinone A,Tan A)對大鼠腦缺血再灌注損傷腦組織和血清中NO含量和NOS、誘導(dǎo)型一氧化氮合酶(iNOS)活性變化的影響,探討其保護(hù)作用的可能分子生物學(xué)機(jī)制。1 材料與方法1.1 動物 健康Wistar大鼠,雄性,清潔級,共40只,體質(zhì)量(25030) g,廣西醫(yī)科大學(xué)動物實驗中心提供。1.

9、2 分組及給藥 將大鼠隨機(jī)分為假手術(shù)組、缺血再灌注組、Tan A低劑量組及Tan A高劑量組,每組10只。TanA低劑量組(15 mg/kg)和高劑量組(30 mg/kg)均于術(shù)前連續(xù)灌胃給藥3 d,每日1次,假手術(shù)組和缺血再灌注組給予等量的生理鹽水灌胃。第3 日給藥后1 h建立局灶性腦缺血90 min再灌注24 h動物模型。1.3 造模 參照文獻(xiàn)3方法制備大鼠局灶性腦缺血再灌注模型。采用頸外動脈插入線栓法,各組均進(jìn)行左側(cè)大腦中動脈栓塞。采用石蠟線栓,直徑約0.27 mm,插入深度約18 mm,此時線栓頭位于大腦中動脈起始部。缺血90 min時,抽提線栓實現(xiàn)再灌注。神經(jīng)功能缺陷評分按照Longa等3評分標(biāo)準(zhǔn),分?jǐn)?shù)在13分為模型成功。1.4 HE染色病理形態(tài)學(xué)觀察 再灌注24 h,各組隨機(jī)取5只大鼠,用生理鹽水和多聚甲醛進(jìn)行心臟灌流固定,斷頭取腦。在左側(cè)大腦半球距離嗅球尖端711 mm之間冠狀切取約5 mm厚腦組織塊,固定、脫水、包埋成臘塊,連續(xù)切片,厚5 m。連取5張作HE染色,觀察病理形態(tài)學(xué)改變。1.5 指標(biāo)檢測 再灌注24 h,大鼠均內(nèi)眥取血,置于干燥試管中,離心,然后將上清液置于干凈EP管中,低溫保存,用于測定NO、NOS和iNOS。取血完畢后立即將各組大鼠斷頭取腦,冰盤上快速取一側(cè)大腦皮層,用冰冷生理鹽水沖洗掉血液