大鼠肾切除术后留存肾代偿早期细胞凋亡状态和collectrin基因表达关系的研究

目的探讨调控脏器形态稳定的重要因素一细胞凋亡和新基因Collectrin在肾代偿性生长中的作用。方法用荧光染色、DNA梯度电泳分析、原位DNA片段末端标记等凋亡检测的手段,RT-PCR、免疫组织化学等Collectrin基因表达研究手段系统研究青、老年大鼠正常肾及代偿肾内细胞凋亡情况及Collectrin基因表达的差异。结果青年正常肾无细胞凋亡表现,而老年正常肾皮、髓质小管均有细胞凋亡存在,且皮质凋亡水平高于髓质;青年肾代偿3d时细胞凋亡明显增加,且髓质高于皮质,老年肾代偿3d时,留存肾细胞凋亡水平明显降低,且以皮质降低更为明显。这些过程都伴随着Collectrin基因表达的同步变化。结论凋亡是肾代偿性生长形态学改变的重要组成部分,肾代偿性生长的年龄差异与细胞凋亡有关,同时也和Collectrin基因的表达有关。     

Histochemical changes effected by aldosterone on compensatory renal growth in the rat

The activity of succinic dehydrogenase, adenosine triphosphatase, alkaline phosphatase and cytochrome oxidase was studied histochemically in the remaining kidney of male albino rats which had been subjected to unilateral nephrectomy and were subsequently treated with aldosterone. A marked increase in the activity of succinic dehydrogenase, adenosine triphosphatase and alkaline phosphatase was noted on the initial postoperative days. The increase noted in succinic dehydrogenase activity is considered particularly important because in the control group succinic dehydrogenase activity remained unchanged throughout the experiment.     

Effects of uninephrectomy and mercuric chloride on renal glutathione homeostasis

The effects of uninephrectomy and i.v. injections of inorganic Hg on renal glutathione(GSH) homeostasis were studied in rats. Compensatory renal growth occurred in all uninephrectomized (NPX) rats 12 days after surgery. The weights of, and the amounts of total protein in, the remnant left kidneys from the NPX rats were significantly greater than those of the corresponding left kidneys from sham-operated (SHAM) rats. The concentration of GSH in samples of whole kidney, cortex and outer stripe of the outer medulla increased after uninephrectomy, with the most striking changes occurring in the outer stripe of the outer medulla. The concentration of GSH in all samples from the SHAM and NPX rats was greater after the administration of a low, nontoxic dose of HgCl2 (0.5-mumol/kg). As with uninephrectomy alone, the increases due to inorganic Hg in both SHAM and NPX rats were greatest in the outer stripe of the outer medulla. The concentration of GSH increased further with a higher, toxic dose of HgCl2 (2.0-mumol/kg). Increasing the dose of HgCl2 to 3.0-mumol/kg resulted in more severe damage to the kidneys of all rats and in decreased concentration of renal GSH. The concentration of Hg under the same conditions as above was also measured, and closely paralleled that of GSH, with the greatest differences occurring in the outer stripe of the outer medulla. To explain these results, we hypothesize that both during compensatory renal growth and after administration of low, nontoxic to mildly toxic doses of Hg, GSH synthesis is induced. At higher, more toxic doses of Hg, GSH depletion becomes more prominent.     

Effect of cyclosporine a on hepatic compensatory growth: role of calcium status

Human alpha(1A)-, alpha(1B)-, and alpha(1D)-adrenergic receptors were tagged at their amino termini with FLAG epitopes and stably expressed in human embryonic kidney (HEK)293 cells. Tagged receptors demonstrated a wild-type pharmacology and mobilization of intracellular Ca(2+). After solubilization and immunoprecipitation, monomers, dimers, and trimers of each subtype were apparent on Western blots. Further denaturation with 6 M urea reduced most oligomers to monomers. Deglycosylation reduced the molecular size of alpha(1A)-, and to a lesser extent alpha(1B)- and alpha(1D)-adrenergic receptors. Radioligand binding site density was highest for alpha(1A)- and much lower for alpha(1B)- and alpha(1D)-adrenergic receptors, but did not correlate with protein expression. Commercial anti-alpha(1)-adrenergic receptor antibodies did not recognize the tagged receptors in Western blots of cell lysates, and substantial cross-reactivity was still observed after solubilization and immunoprecipitation. Surprisingly, only receptor monomers were apparent after photoaffinity labeling with (125)I-arylazidoprazosin, and the intensity of photoaffinity-labeling correlated with the density of radioligand binding sites. We conclude that epitope-tagged alpha(1)-adrenergic receptors exist as both monomers and oligomers in HEK293 cells, but there is substantial discrepancy between protein and binding site expression. Because only monomers are detected by photoaffinity labeling, dimers and trimers observed on Western blots may be pharmacologically inactive.     

Functional correlates of compensatory renal hypertrophy

The functional correlates of compensatory renal hypertrophy were studied by micropuncture techniques in rats after the removal of one kidney. The glomerular filtration rate increased to roughly the same extent in the whole kidney and in individual surface nephrons, resulting in a greater amount of sodium delivered to the tubules for reabsorption. The fraction of the glomerular filtrate absorbed [determined from the tubular fluid-to-plasma ratio (TF/P) for inulin] remained unchanged in both proximal and distal portions of the nephron. The way in which the tubules adjusted to nephrectomy, however, differed in proximal and distal convolutions. After nephrectomy, the reabsorptive half-time, indicated by the rate of shrinkage of a droplet of saline in a tubule blocked with oil, was unchanged in the proximal tubule but significantly shortened in the distal convoluted tubule. Nevertheless, steady-state concentrations of sodium in an isolated raffinose droplet in the distal as well as the proximal tubule were the same in hypertrophied kidneys as in control animals. Possible reasons for this paradox are discussed.Transit time through the proximal tubules was unchanged by compensatory hypertrophy, but transit time to the distal tubules was prolonged.Changes in renal structure resulting from compensatory hypertrophy were also found to differ in the proximal and the distal protions of the nephron. Although tubular volume increased in both protions, the volume increase was twice as great in the proximal tubule as in the distal. In order, therefore, for net reabsorption to increase in the distal tubule, where the changes in tubular volume are not so marked, an increase in reabsorptive capacity per unit length of tubule is required. This increase is reflected in the shortening of reabsorptive half-time in the oil-blocked distal tubule that was actually observed.     

Effect of amiloride on digitalis-induced electrocardiographic changes.

In 10 out of the 13 healthy subjects a single oral dose of 1.25 mg of digoxin induced S-T-J depression and T wave flattening in the exercise ECG. Treatment with potassium-sparing diuretic, amiloride, at a dose of 5 mg twice daily for one week reversed the digoxin-induced S-T-J depression but had no effect on the T wave changes.     

Effect of potassium infusion on renal function in ANF-transgenic mice.

Transgenic mice expressing an ANF fusion gene in the liver were used to study renal function before and during an intravenous KCl load. These animals are characterized by a 10- to 20-fold elevation in plasma ANF concentration, and by a reduction in arterial blood pressure by 20-30 mm Hg, compared to nontransgenic littermates. Before the KCl infusion, renal excretions of fluid, sodium, potassium, and chloride were not different from corresponding values in the nontransgenic sibling mice. Glomerular filtration rates were slightly lower in the transgenic animals. During the KCl infusion, diuresis, saluresis, and kaliuresis were found in both groups. However, salt and water excretion, but not potassium excretion, were significantly greater in the transgenic group. In a separate series, plasma aldosterone concentrations were significantly higher in the transgenic, compared to the nontransgenic mice. These data are interpreted as indicating that antinatriuretic mechanisms, including aldosterone-dependent sodium reabsorption in the cortical collecting tubule, can counteract the effect of ANF to inhibit sodium reabsorption in the medullary duct system, thus allowing maintenance of salt balance. Furthermore, a reduced tubular flow rate at the aldosterone-sensitive site would ensure normal potassium excretion despite the elevated mineralocorticoid level. During KCl infusion, the known increase in tubular delivery of salt and water to the duct would allow full expression of the downstream ANF effect, accounting for the relatively greater diuresis and saluresis in the transgenic mice. We conclude that both renal and adrenal actions of ANF can be rendered ineffective by countervailing mechanisms, suggesting an explanation for the apparent lack of biological activity of endogenously elevated plasma NAF in some disease states.     

酒精对未成年小鼠体格发育的影响

目的研究酒精对未成年小鼠体格发育的影响。方法用不同剂量的酒精（0、12．5％、25％和50％）灌喂8周龄雌性小鼠,并对小鼠体重及身长进行动态的观测。结果高剂量组未成年小鼠体重和身长增长分别在20d和60d变得迟缓;中剂量组未成年小鼠体重和身长增长分别在70d和90d变迟缓。结论长期摄入高、中浓度酒精对未成年小鼠体格发育有抑制作用。     

Distal renal tubular acidosis in mice that lack the forkhead transcription factor Foxi1

While macro- and microscopic kidney development appear to proceed normally in mice that lack Foxi1, electron microscopy reveals an altered ultrastructure of cells lining the distal nephron. Northern blot analyses, cRNA in situ hybridizations, and immunohistochemistry demonstrate a complete loss of expression of several anion transporters, proton pumps, and anion exchange proteins expressed by intercalated cells of the collecting ducts, many of which have been implicated in hereditary forms of distal renal tubular acidosis (dRTA). In Foxi1-null mutants the normal epithelium with its two major cell types - principal and intercalated cells - has been replaced by a single cell type positive for both principal and intercalated cell markers. To test the functional consequences of these alterations, Foxi1(-/-) mice were compared with WT littermates in their response to an acidic load. This revealed an inability to acidify the urine as well as a lowered systemic buffer capacity and overt acidosis in null mutants. Thus, Foxi1(-/-) mice seem to develop dRTA due to altered cellular composition of the distal nephron epithelium, thereby denying this epithelium the proper gene expression pattern needed for maintaining adequate acid-base homeostasis.     

小鼠心肌转化生长因子β1表达与依普利酮的影响

目的：观察高选择性醛固酮受体拮抗剂依普利酮对鸟苷酸环化酶偶联受体-A基因敲除小鼠心肌转化生长因子β1表达的影响，并对其逆转心室重构的分子机制进行探讨。 方法：实验于2005-06／2006-04在河北省人民医院心内科、日本奈良县立医科大学第一内科完成。①实验材料：鸟苷酸环化酶偶联受体-A基因敲除小鼠20只由日本国立循环器病中心岸本一郎教授馈赠，雄性，12周龄，基因背景为清洁级C57BL／6小鼠，随机数字表法分为空白对照组6只、依普利酮组7只、肼苯哒嗪组7只。另取同龄野生型小鼠7只作为野生组。实验过程中对动物的处置符合动物伦理学标准。②实验方法：依普利酮组每天通过饲料给予100mg／kg依普利酮，肼苯哒嗪组每天通过饮用水给予10mg／kg肼苯哒嗪，均给药4周。空白对照组与野生组不进行任何干预。③实验评估：每周检测小鼠尾动脉收缩压及体质量。各组小鼠于16周龄时采用腹主动脉抽血法处死，称取心脏重量，计算心脏重量与体质量的比值。心脏切片行Masson三色染色，并利用图像分析系统测量心肌胶原容积分数、心肌血管周围胶原面积和管腔面积之比。实时定量PCR法检测心室胶原纤维Ⅰ、胶原纤维Ⅲ、心肌转化生长因子β1 mRNA在心肌组织的表达。 结果：①心室重构指标检测：与野生组比较，空白对照组收缩压、心脏重量，体质量、心肌胶原容积分数、心肌血管周围胶原面积，管腔面积均显著升高（P〈0．01）。与空白对照组比较，依普利酮组上述4项指标均显著下降（P〈0．05或0．01）；肼苯哒嗪组收缩压明显下降（P〈0．01），心脏重量，体质量、心肌胶原容积分数、心肌血管周围胶原面积，管腔面积则明显升高（P〈0.05）。②心肌纤维化情况：与空白对照组比较，依普利酮治疗4周后小鼠心肌纤维化得到改善，?     

Bereaved parents' perception of the grandparents' reactions to perinatal loss and the pregnancy that follows

This article presents bereaved parents' perceptions of their parents' (the grandparents) reactions at the time of loss and in the pregnancy that follows. Data originated from two phenomenological studies conducted to understand bereaved parents' experiences during their loss and subsequent pregnancy. However, this article reports a secondary thematic analysis focused on bereaved parents perceptions of the grandparents' support (or lack of) at the time of loss and during the pregnancy following loss. Our findings illustrate some families found the means to share their grief at the time of loss in a constructive manner, while in others the intergenerational relationship was strained. Most important to parents was intergenerational acknowledgment of the ongoing relationship to the deceased child as an important, though absent family member, especially during the pregnancy that followed. Those supporting bereaved families can play an important role in helping intergenerational communication around perinatal loss and the subsequent pregnancy.     

IGF-1, IGFBP-3, VEGF and MMP-9 levels and their potential relationship with renal functions in patients with compensatory renal growth

BACKGROUND: Mechanisms of compensatory renal growth (CRG) still remain a mystery. Various growth factors, including growth hormone, insulin-like growth factor-1 (IGF-1) have been implicated in different forms of CRG. AIMS: To investigate the serum levels of IGF-1, vascular endothelial growth factor (VEGF - role in vascular remodelling), matrix metalloproteinase-9 (MMP-9 - essential for normal nephrogenesis) and correlation of renal function in patients with unilateral nephrectomized, agenesis and hypoplasic kidney. METHODS: Thirty patients were included in this study. In group I, there were 10 patients with unilateral nephrectomy, while in group II, there were 10 patients with unilateral agenesis. As for group III, there were 10 patients with unilateral hypoplastic kidney. The serum levels of IGF-1, IGF-binding protein-3 (IGFBP-3), VEGF and MMP-9 were studied in all the cases. Clearance of creatinin (Ccr) and protein excretion were examined in the 24 h urine. CRG was determined with ultrasonography and scintigraphy. Twenty-six control subjects were also studied. RESULTS: The levels of IGF-1, IGFBP-3, VEGF and MMP-9 were significantly higher in patients than in the control subjects (P < 0.001). Ccr and protein excretion levels were different in study groups than in those of the control group (P < 0.01). There were positive correlations between the serum levels of IGF-1 with IGFBP-3; IGF-1 with MMP-9; IGFBP-3 with MMP-9 (r = 0.825, P = 0.0001; P < 0.001 r = 0.611; P < 0.001 r = 0.585, respectively). There were negative correlations between GFR and the serum levels of IGF-1, IGFBP-3 and MMP-9 (P < 0.01 r = -0.708; P = 0.002 r = -0.803; P < 0.05 r = -0.442, respectively). Furthermore, there were positive correlations between proteinuria and the serum levels of IGF-1, IGFBP-3 and MMP-9 (P = 0.039 r = 0.600; P < 0.05 r = 0.456; P < 0.05 r = 0.424). CONCLUSIONS: Increased IGF-1, IGFBP-3, VEGF and MMP-9 were observed in CRG in the follow-up period. IGF-1 and MMP-9 seemed to have increased in patients with CRG in defiance of the development of fibrosis. Moreover, IGF-1 and MMP-9 seem to be associated with reduced renal function and proteinuria.     

Effect of tryptophan-N-formylated gramicidin on growth of Plasmodium berghei in mice.

The effect of tryptophan-N-formylated gramicidin (NFG) on the growth of Plasmodium berghei in mice was tested in three different experiments. NFG was shown to be capable of inhibiting the growth of the parasite in a dose-dependent way, although its action did not result in elimination of the parasite and was only temporary, preventing mice from early death, presumably due to cerebral malaria, but not from fatal generalized malaria. Intriguingly, a similar observation was made with two other drugs, (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine, an inhibitor of viral and eukaryotic DNA polymerases, and the presumed topoisomerase II inhibitor, a bisquaternary quinolinium salt. A rise in the level of parasitemia after 8 days, despite continued treatment, was not due to parasite-induced reticulocytosis, as demonstrated in experiments in which this condition was induced artificially. NFG was added in the form of lipid vesicles in which the peptide had been incorporated. The inhibitory action of NFG was not modulated by the lipid composition of the vesicles. Control experiments did not demonstrate any toxicity of NFG when it was administered in lipid vesicles. The main observation is that NFG is able to inhibit the growth of a malaria parasite in vivo at concentrations that are well tolerated by the host.     

小鼠心肌转化生长因子β1表达与依普利酮的影响

目的:观察高选择性醛固酮受体拮抗剂依普利酮对鸟苷酸环化酶偶联受体-A基因敲除小鼠心肌转化生长因子β1表达的影响,并对其逆转心室重构的分子机制进行探讨.方法:实验于2005-06/2006-04 在河北省人民医院心内科、日本奈良县立医科大学第一内科完成.①实验材料:鸟苷酸环化酶偶联受体-A基因敲除小鼠20只由日本国立循环器病中心岸本一郎教授馈赠,雄性,12周龄,基因背景为清洁级C57BL/6小鼠,随机数字表法分为空白对照组6只、依普利酮组7只、肼苯哒嗪组7只.另取同龄野生型小鼠7只作为野生组.实验过程中对动物的处置符合动物伦理学标准.②实验方法:依普利酮组每天通过饲料给予100 mg/kg依普利酮,肼苯哒嗪组每天通过饮用水给予10 mg/kg肼苯哒嗪,均给药4周.空白对照组与野生组不进行任何干预.③实验评估:每周检测小鼠尾动脉收缩压及体质量.各组小鼠于16周龄时采用腹主动脉抽血法处死,称取心脏重量,计算心脏重量与体质量的比值.心脏切片行Masson三色染色,并利用图像分析系统测量心肌胶原容积分数、心肌血管周围胶原面积和管腔面积之比.实时定量PCR法检测心室胶原纤维Ⅰ、胶原纤维Ⅲ、心肌转化生长因子β1 mRNA在心肌组织的表达.结果:①心室重构指标检测:与野生组比较,空白对照组收缩压、心脏重量/体质量、心肌胶原容积分数、心肌血管周围胶原面积/管腔面积均显著升高(P ＜ 0.01).与空白对照组比较,依普利酮组上述4项指标均显著下降(P ＜ 0.05或0.01);肼苯哒嗪组收缩压明显下降(P ＜ 0.01),心脏重量/体质量、心肌胶原容积分数、心肌血管周围胶原面积/管腔面积则明显升高(P ＜ 0.05).②心肌纤维化情况: 与空白对照组比较,依普利酮治疗4周后小鼠心肌纤维化得到改善,心脏重量/体质量、心肌胶原容积分数、心肌血管周围胶原面积/管腔面积3项量化指标均降低;肼苯哒嗪治疗4周后表现为心肌纤维化加重,3项量化指标相应增加.③心肌胶原纤维Ⅰ、胶原纤维Ⅲ及心肌转化生长因子β1 mRNA的表达:与空白对照组比较,依普利酮治疗4周后小鼠胶原纤维Ⅰ、胶原纤维Ⅲ及心肌转化生长因子β1的mRNA表达均下降;肼苯哒嗪治疗4周后三者mRNA的表达均升高.结论:依普利酮可独立于血压改善小鼠心肌纤维化和心室重构,其作用机制可能与抑制心室肌高表达的心肌转化生长因子β1有关.     

Effect of lithium and amiloride on collecting tubule transport enzymes.

In humans and animals, the administration of Li or amiloride results in a defect in urinary acidification. Both agents are thought to cause this by a voltage-dependent mechanism in the distal nephron. This study was designed to determine the effects of chronic Li and amiloride administration on the two main transport enzymes in rat nephron collecting tubule, the Na-K-adenosine triphosphatase (ATPase) and the H(+)-ATPase. We also examined the effects of both agents on these enzymes in vitro. Amiloride administration resulted in a decrease in Na-K-ATPase and H(+)-ATPase activities in cortical collecting tubule and medullary collecting tubule. Therapeutic concentrations of amiloride in vitro inhibited Na-K-ATPase activity, but only in cortical collecting tubule. The effects of Li administration were different; it decreased Na-K-ATPase and H(+)-ATPase in both cortical collecting tubule and medullary collecting tubule. In cortical collecting tubule, the inhibitory effect on H(+)-ATPase activity was seen in vitro at a Li concentration similar to that found in urine. In contrast to the effect of Li on the H(+)-ATPase, in vitro Li stimulated Na-K-ATPase activity. These results suggest that the mechanism of action whereby these two agents result in distal renal tubular acidosis in humans and animals are different. In the collecting tubule, amiloride appears to act solely through a voltage-dependent mechanism by inhibiting cortical collecting tubule Na-K-ATPase. Li, by contrast, appears to have an additional effect in the cortical collecting tubule to inhibit the H(+)-ATPase. The biochemical differences seen with these drugs may explain the more severe acidemia universally found in animals after chronic Li administration.     

Effect of intrathecal nocistatin on the formalin-induced pain in mice versus that of nociceptin/orphanin FQ

The effect of intrathecal nocistatin on formalin-induced pain in mice was investigated and compared with that of nociceptin/orphanin FQ (Noc/OFQ) to get information on the functional relationship between nocistatin and Noc/OFQ in the spinal cord. Subcutaneous injection of formalin into the hindpaw induced biphasic pain behaviors. Nocistatin, 1 pg, given intrathecally 1 min before 2% formalin injection, significantly attenuated the first phase of the formalin-induced pain. Also, 10 to 1000 pg of nocistatin, given 10 min after formalin injection, significantly inhibited the second phase of the formalin test. Naloxone, 5 mg/kg i.p., failed to antagonize inhibitory effects of nocistatin on either phase of the formalin-induced pain, indicating that analgesic effects of nocistatin were unrelated to the classic opioid system. At 1 to 100 pg, Noc/OFQ exerted no influence on either phase of the 2% formalin-induced pain. However, at 1% formalin, Noc/OFQ significantly aggravated the second phase at 10 pg but not the first phase at 1 to 1000 pg. This aggravating effect of Noc/OFQ was completely reversed by 10 pg of nocistatin. At 0.3 and 1 microg, Noc/OFQ, but not nocistatin, significantly inhibited both phases of the 2% formalin-induced pain. Suppressive effects of 1 microg of Noc/OFQ on the formalin-induced pain were not affected by 1 microg of nocistatin. These results suggest that Noc/OFQ might be involved in the second phase of the mouse formalin test and that, under such pathophysiological conditions, nocistatin could exhibit antagonism against Noc/OFQ at the spinal level.     

磁场对小鼠一氧化氮生成及生长发育的影响

目的 探讨磁场对小鼠血小一氧化氮（NO）生成及对小鼠生长发育的影响。方法 将小鼠置于同磁场（30mT)不同曝磁时间（30min、60min、1d、1周、1月）,同时间（60min）不同磁场（10mT、20mT、30mT）中,观察磁场对小鼠血清NO含量的影响及小鼠活动状态、存活数、体质量变化。结果 在30mT磁场中曝磁60min,NO含量明显增加,与对照组比较差异有显著性意义（P＜0．01）;曝磁1d,NO含量有所下降,但仍高于对照组（P＜0．05）;曝磁1周、1月,NO含量则逐渐增高,明显高于对照组（P＜0．001）及曝胶60min、1d、1周组。同时随着曝磁时间的延长,小鼠活动减少,食欲减退,体质量下降,存活数减少。均曝磁60min时,只有30mT场强使NO含量显著增加,与对照组比较差异有非常显著性意义（P＜0．01）,其它场强时NO含量无明显变化。该实验条件,使NO含量增加,又可适当抑制其生成的最佳场强为30mT,作用时间为60min。结论 磁场对NO生成有双向调节作用;短时间曝磁,机体调节性NO生成增加,维持内环境稳定;长时间曝磁,NO生成过多,影响小鼠生长发育。