痛泻要方及拆方对腹泻型肠易激综合征模型大鼠结肠组织水通道蛋白3表达的影响

[目的]观察痛泻要方及拆方对腹泻型肠易激综合征（D-IBS）模型大鼠结肠组织水通道蛋白3（aquaporin3,AQP3）表达的影响,探讨痛泻要方的作用机制。[方法]采用慢性应激与束缚相结合方法建立D-IBS大鼠模型;免疫组化法检测AQP3含量;RT-PCR法检测AQP3mRNA的表达。[结果]与对照组比较,模型组和痛泻要方组结肠组织中AQP3表达显著下调（P〈0.01）;与模型组比较,痛泻要方与方中去陈皮组的结肠组织中AQP3表达均上调（P〈0.01）;而与方中去白术或去白芍组差异无统计学意义。[结论]痛泻要方中＂补脾止泻＂药主要是白术和白芍,并且其补脾止泻的作用机制之一可能与上调结肠组织AQP3表达有关。     

Evidence for a role of dystroglycan regulating the membrane architecture of astroglial endfeet

The dystrophin-dystroglycan complex (DDC) is a molecular array of proteins in muscle and brain cells. The central component of the DDC is dystroglycan, which comprises α- and β-subunits. α-Dystroglycan (α-DG) binds to extracellular matrix components such as agrin, whereas β-dystroglycan (β-DG) is a membrane-spanning protein linking α-DG to the cytoskeleton and other intracellular components such as α-syntrophin. In astrocytes, α-syntrophin binds to the water channel protein aquaporin-4 (AQP4). Recently, it has been shown that AQP4 expression is unaltered in agrin-knockout mice, but that formation of orthogonal arrays of particles (OAPs), consisting of AQP4, is abnormal. As the brain-selective deletion of the DG gene causes a disorganization of the astroglial endfeet, we investigated whether DG deletion has an impact on AQP4. Western blotting revealed reduced AQP4 in the parenchymal but not in the superficial compartment of the astrocyte-conditioned DG-knockout mouse brain. Accordingly, immunohistochemical stainings of AQP4 revealed a selective loss of AQP4 in perivascular but not in superficial astroglial endfeet. In both superficial and perivascular endfeet of the DG-knockout brain, we observed a loss of OAPs. We conclude that in the absence of DG the majority of superficial AQP4 molecules did not form OAPs, and that expression of AQP4 in perivascular endfeet is compromised. However, the decreased number of perivascular AQP4 molecules obviously did form a few OAPs, even in the absence of DG.     

Aquaporin-2 urinary excretion in preterm infants: relationship to diuresis and vasopressin

Aims: Few investigations have explored the urinary aquaporin-2 (u-AQP2) excretion pattern after birth in preterm infants with conflicting results regarding the correlation between u-AQP2, urinary osmolality and vasopressin. The aims of this study were to evaluate u-AQP2 excretion during the first week of life in preterm infants, to correlate u-AQP2 with other markers of renal function and to investigate the relationship between u-AQP2, urinary tonicity and arginine-vasopressin in the immature kidney. Methods: In infants born less than 33 weeks daily diuresis, u-AQP2, urinary arginine-vasopressin, urine and plasma tonicity, creatinine and electrolytes were measured through the first 7 days of life. Results: Fifty-five infants were evaluated. u-AQP2 excretion showed the following profile: the highest u-AQP2 levels were found on day 2 and values remained significantly higher until day 5 with respect to day 1. On day 6, u-AQP2 levels significantly decreased to values closer to those found on day 1. u-AQP2 excretion was not associated with arginine-vasopressin while significant, but weak association was found with urinary tonicity (r = −0.20; −0.32 < r < −0.11; P < 0.05). u-AQP2 excretion and creatinine clearance were significantly associated during the study period (r = 0.19; 0.08 < r < 0.29; P < 0.05). There was a strong association between totally u-AQP2 excretion and diuresis over the week (r = 0.72; 0.66 < r < 0.76; P < 0.0001). Conclusion: Significant variations occur in AQP2 expression levels during the first week of life in preterm infants. AQP2 does not seem to contribute to the urinary concentration ability after birth. Further investigations are required to elucidate the mechanisms underlying the strong association between diuresis and u-AQP2 excretion in early postnatal life.     

清肺化痰胶囊对慢性阻塞性肺疾病大鼠气道上皮水通道蛋白-5表达的实验研究

[目的]通过用清肺化痰胶囊治疗慢性阻塞性肺疾病（COPD）大鼠探讨其对大鼠气道上皮水通道蛋白-5（AQP-5）表达的影响进而探讨中药治疗COPD的作用机制。[方法]36只雄性Wistar成年大鼠随机分为模型组、空白组、清肺化痰组、氨溴索组、痰热清组、红霉素组。造模并干预后,免疫组化及图像分析法观察并测定各组AQP-5水平,酶联免疫吸附测定法（ELISA法）测定各组肺组织匀浆中性粒细胞弹性蛋白酶（NE）水平。[结果]肺细支气管上皮细胞AQP-5蛋白面积百分比、积分光密度、肺组织匀浆NE水平模型组明显低于清肺化痰组、沐舒坦组、红霉素组、痰热清组和空白组（P〈0．05）;清肺化痰组与空白组比较差异无统计学意义（P〉0．05）。[结论]清肺化痰胶囊能降低NE的含量,调节AQP-5的表达,调节黏蛋白分泌,从而改善黏液高分泌状态,起到缓解COPD临床症状、促进排痰、提高生活质量的目的。     

醒脑静合生脉注射液对大鼠脑出血后脑组织内水通道蛋白表达的影响

目的:探讨醒脑静合生脉注射液对大鼠脑出血后脑组织内水通道蛋白-4(AQP4)表达的影响。方法:将SD大鼠随机分为脑出血组(ICH)、生理盐水组(NS)、醒脑静合生脉注射液治疗组(XNJSM)、水蛭素治疗组(HIR),每组10只大鼠。采用自体不凝血注入法复制脑出血模型,造模后6 h,XNJSM组ip醒脑静合生脉注射液2 mL.kg-1+10 mL.kg-1(按1∶5比例混合),1次/d,连续3 d;HIR组给予脑内注入水蛭素10 U(5μL)1次。术后72 h取脑组织,HE染色观察各组血肿周围神经细胞形态学改变,免疫组化法及免疫印迹(Western blot)法检测各组血肿周围脑组织AQP4的表达。结果:脑出血后72 h脑组织内AQP4阳性细胞及蛋白表达与NS组比较明显增加(P<0.05),XNJSM组、HIR组脑组织病理形态明显改善,脑组织AQP4表达减少,与ICH组比较差异均有显著性(P<0.05)。结论:醒脑静合生脉注射液能够有效抑制大鼠脑出血后AQP4蛋白的表达,减轻脑水肿,对脑出血后脑组织发挥保护作用。     

肾康片对慢性肾衰竭微炎症状态及水通道蛋白2影响的临床研究

目的 观察肾康片对慢性肾功能衰竭(CRF)患者微炎症状态及水通道蛋白2(AQP2 )的影响,探讨其可能的作用机制.方法 选择2、3期CRF患者70例,随机分为对照组35例肾康片治疗组(治疗组)35例.对照组予西医常规治疗,治疗组在此基础上加用肾康片口服,疗程2 月.结果 治疗组总有效率86.11％优于对照组(71.87％),两组比较(P＜0.05);两组治疗后BUN、CREA均较治疗前显著下降,HGB明显升高(P＜0.05或P＜0.01),但治疗组BUN、CREA下降较对照组更显著(P＜0.01),贫血改善更明显(P＜0.05);治疗后两组炎症因子IL-6、NF-κB、AQP2水平均较治疗前显著下降(P＜0.05或P＜0.01),但治疗组上述指标下降更显著(P＜0.05或P＜0.01).结论 肾康片对CRF患者有肯定疗效,其作用机理与改善CRF患者微炎症状态、纠正水液代谢紊乱有关.     

水通道蛋白1在大鼠角膜碱烧伤新生血管形成中的表达

目的检测大鼠角膜碱烧伤后新生血管形成过程中水通道蛋白1（AQP1）的表达变化,探讨其在角膜新生血管（CNV）形成中的作用。方法碱烧伤诱导CNV模型,将25只sD大鼠按处死的时间点不同分成5组,每组5只。每日裂隙灯下观察CNV的生长情况,并采用免疫组织化学法和RT-PCR法检测AQP1及VEGF在大鼠CNV形成中的表达。结果在正常大鼠角膜组织中,AQP1和VEGF不表达或弱表达。碱烧伤后1d,AQP1表达开始增强,第7天表达最强,14d下降,21d时仍有弱表达。RT—PCR检测显示碱烧伤后AQP1表达增强,在伤后第7天表达最明显,21d后呈弱表达（t1d=3．491,t4d=10．690,t7d=12．936,t14d=10．767,t21d=8．594,P〈0．05）。免疫组织化学检测结果表明,VEGF与AQP1的表达分布相似,强度较弱,统计学分析表明二者的表达水平呈正相关（r=0．834,P〈0．05）。结论AQP1在碱烧伤后角膜巾的表达水平与新生血管的形成明显相关。     

Permeability of the plasma membrane to water and cryoprotectants in mammalian oocytes and embryos: Its relevance to vitrification

The permeability of the plasma membrane to water and cryoprotectants is one of the important factors for determining the suitable condition for the vitrification of mammalian oocytes and embryos. Water and cryoprotectants move slowly through oocytes and early embryos, principally by simple diffusion, in the mouse, bovine, pig, and human. In contrast, water, glycerol, and ethylene glycerol move rapidly through morulae and blastocysts, principally by facilitated diffusion via aquaporin 3, in the mouse and bovine; whereas, in the pig, the permeability to water and these cryoprotectants increases not at the morula stage but at the blastocyst stage and further increases at the expanded blastocyst stage. Dimethyl sulfoxide also moves rapidly via channels other than aquaporin 3 in the mouse. In contrast, propylene glycol moves through morulae and blastocysts principally by simple diffusion in the mouse, bovine, and pig, as through oocytes. Therefore, the permeability of mammalian oocytes and embryos at early stages to water and cryoprotectants is low, but that of embryos at later stages to water and some cryoprotectants is markedly high by channel processes, although species specificity exists in some cases.     

Time course of aquaporin expression after transient focal cerebral ischemia in mice

Cerebral edema contributes to morbidity and mortality in stroke. Aquaporins (AQPs)-1, -4, and -9 have been identified as the three main water channels in the brain. To clarify their role in water movement, we have compared their expression patterns with brain swelling after transient focal brain ischemia. There were two peaks of maximal hemispheric swelling at 1 hr and at 48 hr after ischemia, coinciding with two peaks of AQP4 expression. At 1 hr after occlusion, AQP4 expression was significantly increased on astrocyte endfeet in the core and in the border of the lesion. At 48 hr, AQP4 expression was increased in astrocytes in the border of the lesion over the whole cell. AQP9 showed a significant induction at 24 hr that increased gradually with time, without correlation with the swelling. The expression of AQP1 remained unchanged. These results suggest that AQP4, but not AQP1 or AQP9, may play an important role in water movement associated with the pathophysiology of edema after transient cerebral ischemia in the mouse.