褪黑素对大鼠急性坏死性胰腺炎的干预作用及机制

目的: 观察褪黑素前干预对急性坏死性胰腺炎(ANP)大鼠的胰腺和肺组织的保护作用与硫氧还蛋白-1(Trx-1)表达的关系.方法: 72只♂SD大鼠随机分成ANP模型组(A组)、褪黑素前干预组(M组)、对照组(C组). A组的大鼠腹腔注射6%左旋精氨酸(25 mL/kg体质量), 每次间隔1 h, 共3次, 诱发ANP, 且在诱发ANP前、后0.5 h腹腔注射生理盐水(20mL/kg体质量)各1次;M组的大鼠诱发ANP的方法同A组, 但在诱发ANP前0.5 h腹腔注射0.25%褪黑素(20 mL/kg体质量)1次, 替代生理盐水;C组的大鼠腹腔注射相当于A组各次注射用量的等容积生理盐水. 每组术后6 h、12 h及24 h时点分批处置大鼠. 抽血测定Trx-1、白介素-6(IL-6)、谷胱甘肽(GSH)、总超氧化物歧化酶(T-SOD)、丙二醛(MDA)的含量;取胰腺和肺组织做病理学检查.结果: 大鼠胰腺组织的病理变化和病理学评分证实左旋精氨酸导致A组的ANP. 与A组比较, M组胰腺和肺组织的病理损伤显著减轻. 与C组比较, A组的大鼠血清的Tr x-1的量在6 h、12 h时点显著降低, 24 h时点显著升高, 呈现出先降低后升高的趋势;与A组比较,M组的大鼠血清的Trx-1的量在6 h、12 h时点显著增高, 他们表达的峰值前移. 与C组比较,A组的大鼠血清的IL-6、MDA水平显著增高,血清的T-SOD活力、GSH的含量显著降低;与A组比较, M组的大鼠血清的IL-6、MDA水平显著降低, 血清的T-SOD活力、GSH的含量显著增高.结论: ANP可诱导Trx-1的表达;而褪黑素前干预可进一步促进Trx-1的表达, 提高T-SOD活力和GSH水平, 降低IL-6、MDA水平, 故能显著减轻大鼠胰腺和肺组织的病理损伤, 发挥其对胰腺和肺组织的保护作用.     

褪黑素前后干预对左旋精氨酸诱导的实验性急性坏死性胰腺炎大鼠肺胰组织损伤的保护作用

目的探讨褪黑素前、后干预对急性坏死性胰腺炎(acute necrotizing pancreatitis,ANP)大鼠肺和胰腺组织的保护作用。方法将96只SD大鼠随机分成对照组(C组,n=24)、急性坏死性胰腺炎组(A组,n=24)、褪黑素前干预组(M1组,n=24)和后干预组(M2组,n=24)。A组用6%的左旋精氨酸(L-Arginine,L-Arg)腹腔内注射,每次25mL/kg体质量,共3次,注射间隔1h,诱导ANP模型,在首次注射L-Arg前0.5h腹腔注射生理盐水20mL/kg体质量1次;C组同法注射相当于A组各次注射用量的等容积生理盐水;M1和M2组分别在诱导胰腺炎前和后0.5h腹腔内注射0.25%褪黑素(20mL/kg体质量)干预。在末次注射L-Arg后的第6h、第12h和第24h3个时点分批处死大鼠,观察各组对应各时点胰腺和肺组织病理学改变的变化。结果 A组大鼠胰腺和肺组织病理损伤在各时点较C组明显加重(P0.01);M1组胰腺和肺组织病理损伤较A组减轻,尤以第6h、第12h显著(P0.01或0.05)。M2组上述改变介于A组和M1组之间。M1组较M2组病变轻;在第24h,A组血清淀粉酶较C组显著升高(P0.01);M2组淀粉酶较A组降低(P0.05);M1较A组低。结论在ANP肺组织损伤程度与胰腺组织损伤程度密切相关。褪黑素在一定程度上减轻ANP的胰腺和肺损伤。M1组对肺和胰腺组织的保护作用明显强于M2组。     

褪黑素干预对硫氧还蛋白-2表达的影响及胰腺组织的保护作用

目的:观察在大鼠急性坏死性胰腺炎(acute necrotizing pancreatitis,ANP)时胰腺组织中硫氧还蛋白-2(thioredoxin-2,Trx-2)的表达,探讨褪黑素对胰腺保护作用与Trx-2表达的关系.方法:72只♂SD大鼠随机分为ANP组(A组)、褪黑素干预组(M组)、对照组(C组),每组24只.A组、M组腹腔注射6%左旋精氨基酸25 m L/kg体质量3次,诱发ANP;M组在首次注射左旋精氨基酸前0.5 h腹腔注射0.25%褪黑素20 m L/kg体质量,而A组首次注射左旋精氨基酸前0.5 h腹腔注射生理盐水20 m L/kg体质量;C组同法注射等量生理盐水.各组大鼠在末次腹腔注射后6、12、24 h分批处死.光镜下观察胰腺病理改变并进行评分.RTPCR检测胰腺Trx-2 m RNA水平,并检测胰腺组织中丙二醛(malondialdehyde,MDA)和髓过氧化物酶(myeloperoxidase,MPO)含量.结果:A组各时点胰腺病理评分显著高于C组,而Trx-2 m RNA表达较C组显著降低(均P0.05),MPO和MDA较C组显著升高(均P0.05).M组各时点胰腺病理评分较A组降低,Trx-2 m RNA较A组显著升高(P0.05).MPO和MDA较A组显著降低(均P0.05).结论:Trx-2在ANP时的表达显著降低;外源性褪黑素可通过促进Trx-2的表达,减轻胰腺组织的损伤.     

褪黑素对急性坏死性胰腺炎并肝损伤的保护作用及肝Ghrelin的表达

目的观察在大鼠急性坏死性胰腺炎并肝损伤时肝组织中ghrelin的表达,探讨ghrelin在肝脏损伤中的作用及抗氧化剂褪黑素对其的影响和可能机制。方法72只雄性SD大鼠随机分为对照组(C组,n=24)、急性坏死性胰腺炎组(A组,n=24)、褪黑素干预组(M组,n=24)。A组、M组分3次腹腔注射6%左旋精氨酸(L-Arg)1.5 g/kg,诱发急性坏死性胰腺炎,M组在首次注射L-Arg前0.5 h腹腔注射1%褪黑素50μg/kg,C组同法注射等量生理盐水。各组大鼠在末次腹腔注射后6、12、24 h分批处死。光镜下观察胰腺及肝脏病理改变并进行评分,测定血清淀粉酶水平,RT-PCR检测肝脏ghrelin mRNA水平,并检测肝组织中SOD、MDA含量。结果A组各时点胰腺及肝脏病理评分、血清淀粉酶显著高于C组,ghrelin mRNA表达较C组明显降低(P均0.05),SOD较C组降低,而MDA升高(P均0.05)。M组各时点胰腺及肝脏病理评分、血清淀粉酶较A组降低,ghrelin mRNA较A组升高(P0.05),SOD较A组升高,MDA降低(P均0.05)。结论Ghrelin在急性胰腺炎并肝损伤时的表达可能与病变严重程度有关;外源性褪黑素通过对抗氧化应激,可减轻急性胰腺炎的胰腺和肝脏损伤。     

腹腔注射左旋精氨酸诱导急性坏死性胰腺炎大鼠肺损伤的实验研究

目的探讨大剂量左旋精氨酸腹腔注射诱导大鼠急性坏死性胰腺炎相关性肺损伤模型。方法将48只SD大鼠随机分成对照组(C组,n=24)、急性胰腺炎组(A组,n=24)。A组用6%的左旋精氨酸(L-Arginine,L-Arg)腹腔内注射,每次1.5 mg/g体重,共3次,注射间隔1h,诱导ANP和APALI模型;C组同法注射等量生理盐水。在注射完L-Arg后的第6、12和24小时三个时点分批处死大鼠,分别测定两组各时点血清淀粉酶水平,并观察各组对应各时点胰腺和肺组织病理学改变的变化。结果 A组大鼠胰腺和肺组织病理损伤在各时点比C组明显加重(P0.01);在肺损伤评分均呈正相关(r_s=0.374,P=0.046;r_s=0.452,P=0.027)。结论大剂量L-精氨酸分次腹腔内注射可成功诱导急性坏死性胰腺炎相关性肺损伤大鼠模型,ANP肺组织损伤程度与胰腺组织损伤程度密切相关。     

硫氧还蛋白-1在急性坏死性胰腺炎并急性胃黏膜损伤中的作用

目的探讨硫氧还蛋白-1（TRX-1）在实验性急性坏死性胰腺炎（ANP）并急性胃黏膜损伤发病机制中的作用以及抗氧化剂褪黑素对其的影响。方法72只大鼠随机分为对照组（C组,n=24）、ANP组（A组,n=24）和褪黑素干预组（M组,n=24）。A组分3次腹腔内注射6％L-精氨酸（L—Arg）1．5g／kg建立ANP模型;C组同法注射等量生理盐水;M组于首次注射L—Arg前0．5h腹腔内注射1％褪黑素50μg／kg。各实验组大鼠于末次腹腔内注射后6h、12h和24h分批处死。光镜下观察胰腺和胃组织并进行病理学评分,采用免疫组化检测TRX-1在胃黏膜的表达,并检测胃黏膜中MDA、MPO的含量。结果A组各时点胃黏膜TRX-1的染色积分及MDA、MPO的含量明显高于C组（P均〈0．05）;M组各时点胃黏膜中TRX一1的染色积分及MDA、MPO的含量明显低于A组（P均〈0．05）,胰腺和胃组织病理改变较A组明显减轻（P均〈0．05）。结论内源性的TRX-1可能是胃黏膜组织抵御氧化应激损伤的重要因子之一,TRX-1的表达量可能与组织氧化应激损伤的严重程度有关。外源性的褪黑素在ANP时可能通过其抗氧化作用,减轻胃黏膜氧化应激损伤的程度,对胃黏膜有一定的保护作用。     

硫氧还蛋白-1 在急性坏死性胰腺炎大鼠中的表达及褪黑素对其的影响

目的 观察硫氧还蛋白-1(TRX-1)在急性坏死性胰腺炎(ANP)大鼠胰腺组织的表达和褪黑素干预对其的影响.方法 72只雄性SD大鼠随机分成ANP组、褪黑素组和对照组,每组24只.以腹腔注射6%L-Arginine 25 mL/kg体重3次、每次间隔1 h的方法制备ANP模型.褪黑素组在制模前30min腹腔注射0.25%褪黑素20 ml/kg体重;ANP组和对照组大鼠腹腔注射等容积生理盐水.术后6、12、24 h分批处死大鼠.抽血测定血清淀粉酶含量;取胰腺组织行病理学检查,并评分;检测胰腺组织丙二醛(MDA)、髓过氧化酶(MPO)含量;免疫组化检测胰腺组织TRX-1蛋白表达;RT-PCR检测胰腺组织TRX-1 mRNA的表达.结果 ANP组12 h点血清淀粉酶、胰腺组织MDA和MPO以及TRX-1 mRNA和蛋白表达水平分别为(3 012±1 425)u/L、(4.13±1.85)nmol/mg prot、(7.45±1.26)nmol/mg prot、0.68±0.18、66.8±8.1;褪黑素组分别为(1 835±499)U/L、(3.03±2.12)nmol/mg prot、(5.32±1.06)nmml//mgprot、0.50±0.09、80.29±8.14,两组比较均有显著差异(P<0.05).褪黑素组胰腺TRX-1 mRNA和蛋白表达峰值从ANP组的制模后12 h提前到制模后6 h.结论 ANP大鼠胰腺组织TRX-1 mRNA和蛋白表达增高;褪黑素干预能促进胰腺组织早期表达TRX-1 mRNA和蛋白,减轻胰腺组织的损伤.     

乌司他定对急性坏死性胰腺炎大鼠合并肺损伤的影响

目的 探讨乌司他定(UT1)对急性坏死性胰腺炎大鼠(ANP)合并肺损伤时肺内ET-1和NF-κB表达及肺损伤的影响.方法 60只SD大鼠按随机数字法分成假手术组、ANP组和UTI组,各20只.采用胆胰管逆行注射5%牛磺胆酸钠溶液1 ml/kg体重制备ANP模型,假手术组胰管注射等量生理盐水,UT1组在ANP制模成功后即从大鼠尾静脉注射UTI 10 000 U/kg体重.24 h后处死动物,测血清淀粉酶、TNF-α、肺组织湿/干重比,免疫组化法检测肺组织NF-κB和ET-1蛋白表达以及使用TUNEL法检测细胞凋亡.结果 UTI组术后24 h血清淀粉酶、TNF-α和肺湿/干重比分别为(5 648±378)U/L、(89.19±3.54)ng/L和4.55±0.07,较ANP组的(6 799±437)U/L、(183.30±8.18)ng/L和4.89±0.20显著降低(P＜0.05).假手术组末见NF-κB和ET-1表达,未见凋亡细胞.UTI组NF-κB和ET-1阳性表达率分别为(19±3)%和(8±1)%,较ANP组的(25±2)%和(13±1)%显著降低(P＜0.05).UTI组细胞凋亡指数为13.75±1.25,较ANP组的6.90±0.85显著升高(P＜0.05).结论 ANP时肺组织NF-κB和ET-1的高表达可能导致肺损伤.UTI能改善肺微循环,减轻肺炎症性损伤.     

巨噬细胞移动抑制因子在急性坏死性胰腺炎发病中的作用

目的 探讨巨噬细胞移动抑制因子(MIF)在实验性急性坏死性胰腺炎(ANP)发病机制中的作用以及抗炎细胞因子白介素-10(IL-10)对其的影响和意义.方法 92只大鼠随机分为对照组、ANP组和IL-10治疗组.腹腔注射左旋-精氨酸制作ANP模型.治疗组于末次精氨酸注射后第2、5、8 h腹腔内注射IL-10 10 000U.各组再分4 h、12 h、24 h和36 h点.检测血清巨噬细胞移动抑制因子(MIF)水平以及胰腺和肺组织的MIF表达.结果 ANP组MIF在造模后4 h已升至高值,并持续维持在较高水平,波动于(117.82 ± 15.73)μg/L至(120.97 ± 11.24)μg/L,显著高于对照组的血清MIF浓度(P ＜0.01或P ＜0.05);治疗组各时点血清MIF浓度低于ANP组(P ＜0.05).对照组大鼠胰腺组织的外分泌部、肺组织的支气管上皮细胞及肺泡细胞有MIF弱表达,ANP组和治疗组胰腺及肺组织MIF阳性细胞数增加、染色明显增强.结论 (1)MIF水平在ANP早期明显升高,ANP时肺及胰腺组织中MIF表达增强,提示MIF参与了大鼠ANP及肺损伤的发病;(2)抗炎细胞因子IL-10对血清及胰腺和肺组织的MIF水平有抑制作用,IL-10可能减轻实验性ANP的胰腺及肺的损害,对胰腺及肺组织有一定保护作用.     

抗氧化剂对急性坏死性胰腺炎大鼠一氧化氮、丙二醛的影响

目的　探讨抗氧化剂N_乙酰半胱氨酸 (NAC)对急性坏死性胰腺炎 (ANP)大鼠胰腺组织一氧化氮 (NO)及丙二醛(MDA)的影响。方法　雄性SD大鼠 114只 ,随机分成正常对照组 (C组 ,n =3 0 )、急性胰腺炎组 (A组 ,n =42 )和NAC干预组 (N组 ,n= 42 )。A组分 2次腹腔内注射 8%L_精氨酸 (L_Arg) 1 2mg/g诱导ANP ;C组同法腹腔内注射等量生理盐水 ;N组先提前 1小时 (h)腹腔内注射 0 5mol/L的NAC 0 0 5mg/g ,然后同A组方法诱导ANP。在首次注射L_Arg后于 6h、12h、2 4h、3 6h、48h、72h分批处死大鼠 ,观察大鼠胰腺组织NO和MDA水平及胰腺病理变化。结果　N组各时点NO和MDA水平均较A组明显降低 (均P <0 0 1或P<0 0 5) ,N组 12h、2 4h、3 6h、48h、72h的胰腺病理改变较A组的明显减轻 (均P <0 0 1或P <0 0 5)。结论　NAC可降低胰腺组织NO、MAD水平 ,减轻了实验性ANP大鼠的胰腺损害 ,对胰腺组织有保护作用     

Effect of melatonin on the severity of L-arginine-induced experimental acute pancreatitis in rats

AIM: To determine the effect of melatonin pre- and post-treatment on the severity of L-arginine (L-Arg) -induced experimental pancreatitis in rats. METHODS: Male Wistar rats (25) were divided into five groups. Those in group A received two injections of 3.2 g/kg body weight L-Arg i.p. at an interval of 1 h. In group MA, the rats were treated with 50 mg/kg body weight melatonin i.p. 30 min prior to L-Arg administration. In group AM, the rats received the same dose of melatonin 1 h after L-Arg was given. In group M, a single dose of melatonin was administered as described previously. In group C the control animals received physiological saline injections i.p. All rats were exsanguinated 24 h after the second L-Arg injection. RESULTS: L-Arg administration caused severe necrotizing pancreatitis confirmed by the significant elevations in the serum amylase level, the pancreatic weight/body weight ratio (pw/bw), the pancreatic IL-6 content and the myeloperoxidase activity, relative to the control values. Elevation of the serum amylase level was significantly reduced in rats given melatonin following L-Arg compared to rats injected with L-Arg only. The activities of the pancreatic antioxidant enzymes (Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and catalase (CAT)) were significantly increased 24 h after pancreatitis induction. Mela- tonin given in advance of L-Arg significantly reduced the pancreatic CAT activity relative to that in the rats treated with L-Arg alone. In the liver, L-Arg significantly increased the lipid peroxidation level, and the glutathione peroxi-dase and Cu/Zn-SOD activities, whereas the Mn-SOD activity was reduced as compared to the control rats. Melatonin pre-treatment prevented these changes. CONCLUSION: Melatonin is an antioxidant that is able to counteract some of the L-Arg-induced changes during acute pancreatitis, and may therefore be helpful in the supportive therapy of patients with acute necrotizing pancreatitis.     

银杏苦内酯B对急性坏死性胰腺炎大鼠肺组织PAF—R表达的影响

目的观测银杏苦内酯B（BN52021）干预前后ANP大鼠肺组织血小板活化因子受体（PAF-R）mRNA和蛋白质表达的变化,探讨其作用机制。方法180只大鼠随机分为对照组（NC组）、ANP组和BN52021治疗组（BN组）,每组再分为制模后1h、2h、3h、6h、12h、24h6个亚组。逆行胰胆管内注射牛磺胆酸钠诱导ANP。BN组于制模后15min股静脉注入BN52021（0.5mg/100g体重）。各时间点取血检测血清淀粉酶,取胰腺和肺组织行病理学检查,采用RT-PCR和Western blot检测肺组织PAF-R mRNA和蛋白质表达。结果ANP组和BN组各时点血清淀粉酶均高于NC组（P〈0.05）,BN组1h、2h、3h、6h、24h时点均低于ANP组（P〈0.05）。ANP组和BN组胰腺和肺的病理分值均高于NC组,BN组在3h、6h、12h显著低于ANP组（P〈0.05）。ANP组和BN组PAF-R mRNA和蛋白质水平分别在3h和1h显著高于NC组,BN组与ANP组相比无显著差异。结论PAF-R在ANP早期急性肺损伤中起重要作用,BN52021对其表达无显著影响。     

Effects of Chai-Qin-Cheng-Qi Decoction on cefotaxime in rats with acute necrotizing pancreatitis

AIM： To investigate the effect of Chai-Qin-Cheng-Qi Decoction （CQCQD） on cefotaxime （CTX） concentration in pancreas of rats with acute necrotizing pancreatitis （ANP）. METHODS： Sixty healthy male Sprague-Dawley rats were divided randomly into an ANP group （ANP model ＋ CTX, n = 20）, treatment group （ANP model ＋ CTX ＋ CQCQD, n = 20） and control group （normal rats ＋ CTX, n = 20）. ANP models were induced by retrograde intraductal injection of 3.5% sodium taurocholate （1 mL/kg）, and the control group was injected intraductally with normal saline. All rats were injected introperitoneally with 0.42 g/kg CTX （at 12-h intervals for a continuous 72 h） at 6 h after intraductal injection. Meanwhile, the treatment group received CQCQD （20 mL/kg） intragastrically at 8-h intervals, and the ANP and control group were treated intragastrically with normal saline. At 15 min after the last CTX injection, blood and pancreas samples were collected for the determination of CTX concentration using validated high-performance liquid chromatography. Pathological changes and wet-to-dry-weight （W/D） ratio of pancreatic tissue were examined. RESULTS： Serum CTX concentrations in three groups were not significantly different. Pancreatic CTX concentration and penetration ratio were lower in ANP group vs control group （4.4 ± 0.6 μg/mL vs 18.6±1.7μg/mL, P = 0.000; 5% vs 19%, P = 0.000）, but significantly higher in treatment group vs ANP group （6.4 ± 1.7 μg/mL vs 4.4 ± 0.6 μg/mL, P = 0.020; 7% vs 5%, P = 0.048）. The histological scores and W/D ratio were significantly decreased in treatment group vs ANP and control group. CONCLUSION： CQCQD might have a promotive effect on CTX concentration in pancreatic tissues of rats with ANP.     

胰岛β细胞参与急性胰腺炎后胰腺再生过程的研究

目的 探讨胰岛β细胞在实验性急性胰腺炎(AP)后胰腺再生过程中的作用.方法 SD大鼠87只,按数字表法随机分为对照组(15只)、糖尿病组(24只)、AP组(24只)和糖尿病+AP组(24只).采用腹腔注射链脲佐菌素(STZ,60 mg/kg体重)或左旋精氨酸(L-Arg,2.5 g/kg体重,2次)方法分别建立糖尿病和AP模型.术后1、3、5、7d分批处死大鼠.检测血淀粉酶和血糖水平;计算胰腺湿重比;胰腺组织常规病理学检查,计算胰腺坏死面积百分比和组织转化区域百分比;免疫荧光检测胰岛β细胞的再生基因( Reg4)和胰岛素的表达.结果 注射STZ后,大鼠血糖明显升高,注射L-Arg后大鼠胰腺组织水肿、坏死、炎细胞浸润,血淀粉酶明显升高,表明制模成功.制模后第3天糖尿病+ AP组的胰腺坏死面积为(71.6±6.0)％,显著大于AP组的(42.3±4.0)％;第7天的组织转化面积为(45.6±5.4)％,显著小于AP组的(78.5±6.4)％.糖尿病+AP组胰岛β细胞的Reg4和胰岛素表达均较AP组明显减少.结论 STZ破坏了胰岛β细胞,加重精氨酸诱导的AP的损伤,并抑制胰腺的再生过程.     

Melatonin ameliorates acute necrotizing pancreatitis by the regulation of cytosolic Ca2+ homeostasis

ObjectivesThis study aims to investigate the relationship between the protective effects of melatonin in pancreas and the expression of sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) and Na⁺/Ca²⁺ exchanger (NCX) in rats with acute necrotizing pancreatitis (ANP), to verify whether melatonin ameliorates ANP by alleviating calcium overload.MethodsNinety-six male Sprague-Dawley rats were randomly divided into four groups (sham operation group, ANP group, melatonin treatment group, melatonin contrast group). ANP was induced by the retrograde injection of 4% taurocholate (1 ml/kg body weight) into the biliopancreatic duct. Melatonin (50 mg/kg body weight) was administered 30 min before the induction of ANP in the melatonin treatment group. Rats in each group were euthanized at 1, 4, and 8 h after ANP induction. Pancreatic tissues were removed to measure SERCA and NCX levels and cytosolic calcium ion (Ca²⁺) concentration ([Ca²⁺]_i).ResultsAt each time point, SERCA and NCX levels in the melatonin treatment group were significantly higher than that in the ANP group, and lower than that in the sham group and the melatonin contrast group. These levels did not differ between the 4- and 8-h time points in the ANP group. [Ca²⁺]_i in pancreatic acinar cells was higher in the melatonin treatment group than in the sham group and the melatonin contrast group, but lower than in the ANP group, at each time point.ConclusionMelatonin can reduce pancreatic damage via the up-regulation of SERCA and NCX expression, which can alleviate calcium overload in pancreatic acinar cells.     

急性坏死性胰腺炎胰腺组织中褪黑激素受体表达及褪黑激素干预作用

目的 探讨急性坏死性胰腺炎(ANP)胰腺组织中褪黑激素受体MT1表达及褪黑激素(MT)干预作用.方法 54只SD大鼠随机分为假手术组(SO组)、急性坏死性胰腺炎组(ANP组)、MT干预组(MT组),每组18只.应用胰胆管逆行注射牛磺胆酸钠的方法诱导ANP模型,MT组于诱导模型前30 min腹腔注射MT.术后4 h、8 h和12 h分批处死大鼠(每个时间点6只),以免疫组化和实时定量PCR分别检测胰腺组织中MT1蛋白及MT1 mRNA的表达;检测血清淀粉酶、胰腺组织中丙二醛(MDA)、超氧化物歧化酶(SOD)及TNFα的含量,并行胰腺病理检查.结果 (1)ANP组胰腺病理损伤呈进行性加重,MT组胰腺病理损伤较ANP组明显减轻(P＜0.05).(2)淀粉酶、MDA、TNFα水平在ANP组较S0组明显增高(P＜0.05或P＜0.01),而MT组较相应时间点ANP组显著降低[12 h,(2348.00±278.90)U/L比(3194.83±538.10)U/L,(2.255±0.472)μmol/L比(2.960±0.722)μmol/L,(102.929±29.399)ng/L比(378.544±183.454)ng/L,P＜0.05].SOD水平在ANP组各时点较SO组显著降低(P＜0.01),而MT组较ANP组显著升高[12 h,(11.448±1.594)U/L比(8.427±1.950)U/L,P＜0.05].(3)与SO组相比,MT1蛋白及MT1 mRNA表达在ANP组胰腺组织中明显下降(P＜0.05),且随ANP病变加重表达减弱,而MT组表达较ANP组明显增多.结论 MT干预可提高SOD活力,降低MDA、TNFα水平,故能显著减轻ANP时胰腺病理损伤,MT1在ANP发病机制中可能具有重要作用,MT对ANP中的干预作用可能与上调胰腺组织中MT1的表达有关.     

L-精氨酸对哮喘大鼠气道平滑肌细胞增殖的影响

目的 观察L-精氨酸（L-Arg）对哮喘气道重构大鼠气道平滑肌细胞（ASMC）的细胞周期分布及细胞周期调节蛋白（CCRP）表达水平的影响,探讨L-Arg体内干预哮喘大鼠ASMC增殖的可能作用机制。方法实验分成对照组、哮喘组、L-Arg组,建立大鼠哮喘气道重构模型,检测血清NO2^-／NO3^-含量、肺内支气管内管壁和平滑肌层厚度及ASMC核数、ASMC的细胞周期分布以及ASMC内细胞周期素E（cyclin E）、cyclinA、cyclinB、蛋白27^kip1（P27^kip1）的表达。结果 哮喘组大鼠支气管内管壁、平滑肌层的厚度和ASMC数目显著大于对照组（P〈0．05）;L-Arg组大鼠支气管内管壁的厚度、平滑肌层的厚度和ASMC数目显著小于哮喘组（P〈0．05）。哮喘组血清一氧化氮（nitricoxide,NO）水平显著低于对照组（P〈0．05）;L-Arg组血清NO水平显著高于哮喘组（P〈0．01）。哮喘组G0／G1期ASMC比例及P27^kip1表达水平显著低于对照组（P〈0．01）,G2／M＋S期ASMC比例及cyclinE、cyclinA和cyclinB表达水平显著高于对照组（P〈0．01）;L-Arg组G0／G1期ASMC比例及P27^kip1表达水平显著高于哮喘组（P〈0．05）,G2／M＋S期ASMC比例及cyclinE和cyclinA表达水平显著低于哮喘组（P〈0．05）。结论 L-Arg通过调控CCRP的表达水平阻滞细胞从G1期进入S期而抑制哮喘ASMC的增殖。     

Changes of gastric and intestinal blood flow, serum phospholipase A2 and interleukin-1β in rats with acute necrotizing pancreatitis

AIM: To explore the relationship between gastric and intestinal microcirculatory impairment and inflammatory mediators released in rats with acute necrotizing pancreatitis (ANP).METHODS: A total of 64 rats were randomized into control group and ANP group. ANP model was induced by injection of 5% sodium taurocholate under the pancreatic membrane.Radioactive biomicrosphere technique was used to measure the gastric and intestinal tissue blood flow at 2 and 12 h after the induction of ANP, meanwhile serum phospholipase A2 (PLA2) activities and interleukin-1β levels were determined. Pathologic changes in pancreas, gastric and intestinal mucosae were studied. RESULTS: The gastric blood flow in ANP group (0.62±0.06 (P＜0.01) at 2 and 12 h after induction of ANP. The intestinal blood flow in ANP group (0.80±0.07 and (P＜0.01). Serum PLA2 activities (94.29±9.96 and 103.71± 14.40) U/L and IL-1β levels (0.78±0.13 and 0.83±0.20) μg/L in ANP group were higher than those in control group (65.27±10.52 and 66.63±9.81) U/L, (0.32±0.06 and 0.33±0.07) μg/L (P＜0.01). At 2 and 12 h after introduction of the model, typical pathologic changes were found in ANP. Compared with control group, the gastric and intestinal mucosal pathologic changes were aggravated significantly (P＜0.01) at 12 h after induction of ANP. Gastric and intestinal mucosal necrosis, multiple ulcer and hemorrhage occurred.CONCLUSION: Decrease of gastric and intestinal blood flow and increase of inflammatory mediators occur simultaneously early in ANP, both of them are important pathogenic factors for gastric and intestinal mucosal injury in ANP.