Effects of Acute Bilateral Ureteral Obstruction on Deep Nephron and Terminal Collecting Duct Function in the Young Rat

The effects of acute bilateral ureteral obstruction (BUO) of 18-h duration on deep nephron and collecting duct function were studied by micropuncture in 11 weanling rats. After release of BUO glomerular filtration rate was reduced (178±15 vs. 1,343±119 μl/min per g kidney weight in shams), while urine flow was increased averaging 17.5±1.3 vs. 6.8±0.72 μl/min per g kidney weight in controls. There was a marked increase in the absolute and fractional excretion of Na. Single nephron glomerular filtration rate of deep nephrons was reduced in the BUO group, mean 19.4±3.5 vs. 77.0±7.7 nl/min per g kidney weight in shams. Single nephron glomerular filtration rate of superficial nephrons fell to the same extent after relief of BUO. Mean tubular fluid to plasma inulin ratio of fluid from Henle's loop was 2.46±0.20 after relief of BUO vs. 8.23±0.85 in shams. This suggested a reduction in the reabsorption of Na and water before the bend of the loop of Henle, most likely in both the proximal tubule and descending limb. Fluid osmolality was depressed due to a decline in both Na and nonelectrolyte solute content. After release of BUO the percentage of filtered water remaining in the collecting duct (CD) at the base of the papilla was greater than in controls (13.3±2.0 and 1.72±0.01%, respectively) but fell significantly by the tip of the papilla to 7.92±1.12 vs. 1.17±0.02% in controls. These results indicate that water was reabsorbed along the terminal CD after relief of ureteral obstruction. In fact, a greater fraction was reabsorbed in this segment after release of BUO (5.37±1.58%) than after sham operation (0.55±0.15%). Similar changes were seen in Na excretion. Thus alterations in deep nephron function appear to contribute to the natriuresis and diuresis which follow release of BUO while terminal CD function in this model appears intact.     

THE DYNAMICS OF RETICULOENDOTHELIAL BLOCKADE

The dynamics of "reticuloendothelial blockade" were studied in living rabbits and isolated, perfused rabbit livers utilizing gelatin as a blockading agent and Au¹⁹⁸ stabilized in gelatin as a tracer. Employing the above experimental model, the following observations were made. (a) RES blockade was specific and dependent on the surface properties of the particle under study. (b) RES blockade was not caused by saturation of hepatic removal mechanisms. (c) RES blockade was not caused by depletion of demonstrable serum opsonins. (d) RES blockade appeared to correlate with high circulating levels of the blockading agent, per se. Thus, under the conditions employed, the term "reticuloendothelial blockade" was a misnomer. Although specificity of liver macrophage-particle interaction was evident and deserves further study, the data suggest that blockade as usually studied is a laboratory phenomenon induced by the continuing circulation of the blockading agent.     

THE MECHANISM OF BLOCKADE OF THE RETICULOENDOTHELIAL SYSTEM

Rats were injected intravenously with various particulate materials with and without the addition of various stabilizing agents. One hour after the injection of the blockading colloid, a tracer dose of similar or different colloidal material was injected. A half-time clearance rate of the tracer dose greater than 4 minutes was taken as evidence of blockade of the RES. Blockade of the tracer dose occurred when the surface properties of the particles in both blockading and tracer doses were identical. Different particles stabilized by the same agent behaved as identical particles and identical particles stabilized by different agents behaved as different particles. The opsonization of a tracer dose of gelatin-stabilized colloid in vitro by a specific globulin fraction obtained from heterologous and homologous plasma prevented its blockade, while opsonization of both blockading and tracer doses with the same proteins resulted in blockade. However, when both blockading and tracer doses were opsonized with isologous globulins, blockade did not occur.     

FURTHER OBSERVATIONS ON THE MECHANISM OF RETICULOENDOTHELIAL BLOCKADE

The mechanism of the reticuloendothelial "blockade" which followed injection of large quantities of chromic phosphate without exogenous stabilizing material was investigated in Wistar rats. The RE blockade observed for several hours after induction appeared related to the continuing circulation of the chromic phosphate-blockading dose, and a reduction in the size of the particles used enhanced blockade. RE blockade appeared to be particles specific and was not related to a generalized depression of RE-phagocytic cell function. Studies in isolated perfused rat livers appeared to eliminate saturation of particle-specific macrophage clones as a likely explanation of blockade, and blockade could not be explained on the basis of depletion of serum opsonins. In the system employed, it is postulated that blockade occurs when large numbers of circulating particles saturate specific macrophage cell membrane-binding sites rather than from physical stuffing of RE-phagocytic cells.     

ONTOGENY OF THE IMMUNE RESPONSE : II. CORRELATIONS BETWEEN THE DEVELOPMENT OF THE AFFERENT AND EFFERENT LIMBS

The development of the ability of young rats to generate a prompt primary antibody response to polymerized flagellin, with IgM to IgG transition, is correlated in time with the development of structures in the cortex of lymph nodes that localize antigen to spherical areas which subsequently become primary lymphoid follicles. Throughout development the increased magnitude of the antibody response parallels the increased ability of lymphoid structures to retain antigen. During the first week of life primitive lymphoid tissue appears capable of undergoing the initial steps in differentiation toward antibody production in response to neonatal injections of polymerized flagellin. However, further maturation appears to be blocked resulting in a complex immunological state at the age of 2 weeks characterized by increased IgM and decreased IgG antibody response to antigenic challenge at this time. The possible relationship between the block in cellular differentiation toward antibody formation and the ease of tolerance induction is discussed.     

超声在输尿管梗阻性疾病中的诊断价值

目的探讨超声在输尿管梗阻性疾病中的诊断价值。方法对经超声检查的84例输尿管梗阻性疾病进行回顾性分析。结果输尿管梗阻性疾病均具有不同程度的典型超声征象。结论超声可以快速、简捷、准确地诊断输尿管梗阻性疾病,具有较高的临床应用价值。     

磁共振水成像对输尿管梗阻病变诊断的应用

目的探讨磁共振水成像（MRU）对输尿管梗阻病变诊断的价值。方法回顾性分析经手术病理证实的28例输尿管梗阻患者的术前MRU及磁共振成像（MRI）检查资料。结果28例患者中泌尿系结石15例,输尿管炎性狭窄5例,输尿管肿瘤、膀胱癌各2例,肾结核、肾脓肿各2例。MRU能清楚显示梗阻的形态特征,定位准确率达100%。结论MRU结合常规MRI可以对输尿管梗阻病变作出准确的定位和辅助定性诊断。     

THE ROLE OF α-ADRENOCEPTOR BLOCKADE IN THE TREATMENT OF HYPERTENSION

Early attempts to use α-adrenoceptor blockers in the treatment of hypertension were unsuccessful due to a high prevalance of side-effects. Now that the concept of two α-adrenoceptors, α₁ and α₂ has been investigated, specific α, postsynaptic adrenoceptor blocking drugs have become available to treat hypertension. Their efficacy, tolerance and acceptability are discussed, and indications for their usage suggested.     

福辛普利及霉酚酸酯对单侧输尿管梗阻大鼠肾脏TGF-β1表达的影响

目的观察福辛普利及霉酚酸酯对单侧输尿管梗阻(UUO)大鼠肾脏转化生长因子β1(TGF-β1)表达的影响,及其对肾间质纤维化的作用.方法UUO大鼠分别给予霉酚酸酯[Mycophenolate mofetil 25 mg/(kg·d)]、福辛普利[fosinopril 10 mg/(kg·d)]、霉酚酸酯联合福辛普利混悬液灌胃,用RT-PCR的方法检测术后第7天、14天TGF-β1表达量的改变.结果与假手术组相比,UUO组及药物治疗组TGF-β1表达均增高,但UUO组显著高于各治疗组(P<0.05),且联合治疗组更低于单用药组.结论福辛普利及霉酚酸酯可通过下调TGF-β1表达,从而减轻UUO术后肾组织间质纤维化,且联合用药作用更优于单用药.     

THE INFLUENCE OF BETA-ADRENOCEPTOR BLOCKADE ON THE LIPOLYTIC RESPONSE TO EXERCISE

The influence of beta-adrenoceptor blockade on the free fatty acid (FFA) response during and after submaximal exercise was studied in a group of normal volunteers. The study showed that the exercise-induced rise in serum FFA concentrations seen with placebo was reduced after pretreatment with propranolol. Furthermore, the palmitic, stearic, oleic and linoleic acid responses showed progressive attenuation with increasing doses of propranolol. Different beta blockers were studied using comparable doses: metoprolol and nadolol had little effect and produced FFA profiles that were similar to placebo whereas the changes on pindolol were comparable with those on propranolol.     

THE ORIGIN OF THE CELLS IN THE EFFERENT LYMPH FROM A SINGLE LYMPH NODE

The popliteal nodes of sheep were perfused continuously for over 100 hours with a solution containing ³H-thymidine. The labelling pattern of the lymphocytes in the efferent lymph from the perfused nodes showed that under normal conditions not more than 4 per cent of these lymphocytes were actually produced in the node. The transitional cells, large lymphocytes and cells of the plasma cell series which appeared in the lymph following antigenic stimulation of the node were all produced in the node.     

三维超声在输尿管梗阻中的临床应用

目的评价三维超声成像在输尿管梗阻中的临床应用。方法35例输尿管梗阻患者分别经二维超声和三维超声检查,并对两者的图像进行对比分析,并将结果与手术及病理相对照。结果病变经三维超声成像后,较二维超声更清晰,尤其是三维超声成像后可以更清晰地了解病变与输尿管管壁的关系、输尿管管腔及输尿管与病变的空间关系。结论三维超声成像可以获得更丰富的信息,对明确诊断起到重要的作用。     

STUDIES OF THE CELLS IN THE AFFERENT AND EFFERENT LYMPH OF LYMPH NODES DRAINING THE SITE OF SKIN HOMOGRAFTS

Intermediate lymph (efferent from the prefemoral lymph node) was collected for 600 hr from both flanks of each of four sheep that had an autograft of skin on the left flank and a homograft of skin on the right flank. 8 days after the grafts had been applied considerable numbers of large basophilic cells, apparently identical with those that appear during immune responses to conventional antigens, appeared in the lymph draining from the homografts. No such cells appeared in the lymph draining from the autografts. At this time the homografts were already showing signs of rejection and were apparently dead well before the cellular response in the lymph reached a peak, about 350 hr (14–15 days) after the homografts had been applied. During the peak of the response up to 40% of the cells in the lymph were basophilic cells and in one experiment such cells were leaving the lymph node at a rate of 200 million per hr. Peripheral lymph (afferent to the popliteal lymph node) draining from the sites of homografts of skin was collected from five sheep. This lymph contained few white cells (<1000 per mm³) and showed only an insignificant lymphoid cell reaction. Although the percentage of macrophage-like cells was increased significantly there were few signs of a lymphoid cell reaction; the lymph also contained much amorphous debris. Experiments in which the basophilic cells from the efferent lymph were labeled in vitro with thymidine-³H and returned to the sheep by intravenous injections were carried out in six sheep. The presence of the labeled cells in the grafts, blood, and other tissue was detected by liquid scintillation counting of nucleic acid extracts of biopsy and postmortem material and by radioautography. 2–3 labeled cells out of every 1000 injected entered the homografts but hardly any entered the autografts. However, labeled basophilic cells that had originated in response to bacterial antigens entered the homografts with equal facility. It is thus hard to believe that the immunological specificity of a lymphoid cell endows it with a specific "homing" capability. Furthermore, in all the experiments the specific radioactivities of the nucleic acids extracted from the blood mononuclear cells were approximately of the same order as those of the nucleic acids extracted from the homografts. It was concluded that most of the mononuclear cells that infiltrate homografts represent a random selection from the mononuclear cell population of the blood.     

扇形超声显像对输尿管梗阻性疾病的诊断价值

采用扇形超声显像诊断输尿管梗阻性疾病收到了较好的效果，其中扇形超声诊断输尿管梗阻位置的符合率为９４．９％（７４／７８），诊断输尿管梗阻病因的符合率为９１％（７１／７８）。扇形超声较线阵式超声操作更为灵活和轻便，尤其对过于肥胖、受胃肠道气体或粪团干扰较重的患者，扇形超声能弥补线阵式超声检查的许多不足，可做为诊断输尿管梗阻性疾病的首选方法之一。     

EXPANDING ROLE OF ALPHA ADRENOCEPTOR BLOCKADE IN THE TREATMENT OF BENIGN PROSTATIC HYPERPLASIA

SUMMARY This review analyses the expanding role of alpha adrenoceptor blockers in the treatment of BPH and examines the rationale for their use. The safety and efficacy of currently available alpha adrenoceptor blockers is reviewed, with emphasis on the most extensively studied agent, doxazosin. Like other alpha adrenoceptor blockers, doxazosin improves both symptoms of BPH and urinary flow rates by a statistically significant effect compared with placebo. Doxazosin also significantly reduces blood pressure in the 30% of BPH sufferers who also have hypertension; furthermore, there is a beneficial effect on lipid metabolism, which may translate into a reduced risk of coronary heart disease. It is concluded that existing alpha adrenoceptor blockers constitute a valuable adjunct to other BPH therapies, and further refinement of alpha adrenoceptor selectivity based on the alpha-1A subtype in the near future promises even better targeted alpha blockade.     

动态静脉尿路造影后螺旋CT尿路成像对输尿管梗阻的诊断价值

目的:研究动态静脉尿路造影(DIVU)后螺旋CT泌尿系成像(SCTU)对输尿管梗阻的诊断价值。方法:35例患者DIVU示单侧尿路显影不良及输尿管梗阻原因不明,行螺旋CT平扫、多平面重建和容积重建三维重建成像。所有病例均经手术病理证实。结果:35例患者DIVU后行SCTU,诊断输尿管结石18例,炎性狭窄4例,外压性狭窄4例,肿瘤3例,先天性狭窄3例,腔静脉后输尿管1例,双侧肾盂及输尿管重复畸形1例,不能确诊1例。结论:DIVU后SCTU是一种无创、可靠、有效检查方法,可明显提高输尿管梗阻性病变诊断准确性,具有很高的临床应用价值。