Effect of Ultrafiltration on Plasma Concentrations of Atrial Natriuretic Peptide in Haemodialysis Patients

We have investigated the influence of body fluid volume statuson plasma levels of immunoreactive atrial natriuretic peptide(irANP) in eight uraemic patients on chronic haemodialysis,including two diabetics with severely impaired reflex controlof the heart. IrANP was significantly higher in volume-expandeduraemic patients (36±16 pg/ml) than in a group of sevenage and sex-matched normal subjects (14±2 pg/ml), andfell consistently, approaching the normal range after the removalof 2.0–4.3 litres of isotonic plasma ultrafiltrate (byisolated ultrafiltration). Plasma levels of the hormone werestrictly related to right atrial pressure. The irANP responseto ultrafiltration in the two diabetics was similar to thatof the other uraemic patients. The results suggest that theelevated irANP levels found in volume-expanded uraemic patientsdepend largely on fluid overload per Se. The preserved irANPresponse to ultrafiltration of the two diabetics with severeautonomic neuropathy indicates that in chronic renal failureirANP secretion may be regulated independently from autonomicinfluences.     

The Effect of Renal Transplantation on Plasma Atrial Natriuretic Peptide

The changes in plasma atrial natriuretic peptide (ANP) werestudied in four adult patients after cadaveric renal transplantation.In three patients who achieved good renal function, the correctionof volume overload, as reflected by reduction in weight andright atrial pressure, was associated with a steady fall inplasma ANP and a parallel decrease in both fractional excretionof sodium and plasma cyclic guanosine monophosphate. The fourthpatient. with severe acute rejection, developed severe peripheraloedema, and fractional sodium excretion remained low despitehigh values of ANP.     

Renal Response to Atrial Natriuretic Peptide in Nephrotic Syndrome

In six patients with nephrotic syndrome of various aetiology,the increase in absolute and fractional sodium excretion (FE_Na)after a bolus injection of 100 µg -human atrial natriureticpeptide (ANP) was not different from the effect in normal healthysubjects at comparable sodium levels. Glomerular filtrationrate rose in normals as well as in patients. In two patients,however, baseline sodium excretion was very low and the natriureticresponse to ANP was proportionally blunted. The high baselinesodium reabsorption and blunted response to ANP may be explainedas due either to an intrinsic renal defect or to a circulatoryhypovolaemia. The finding of a low plasma ANP in these two patients,however, suggests involvement of a hypovolaemic component.     

Increased Plasma Levels of Atrial Natriuretic Peptide in Patients with Chronic Renal Failure: Effect of Noradrenaline Infusion

Basal plasma atrial natriuretic peptide (ANP) and blood pressurewere measured in 11 patients with chronic renal failure beforerequirement of dialysis, 13 patients on chronic dialysis, and28 control subjects (Study 1). Changes in ANP during noradrenalineinfusion were determined in eight patients with chronic renalfailure before dialysis, 12 patients on chronic dialysis, and17 control subjects (Study 2). ANP was also measured in 14 healthycontrol subjects during angiotensin II infusion (Study 3). Study1 showed a significantly greater ANP in patients before thestage of dialysis (median 23 pg/ml) and in dialysis patients(34 pg/ml) than in control subjects (19 pg/ml) p 0.01 for both.In Study 2, noradrenaline induced an increase in ANP in thenon-dialysed patients (P<0.05) and in the control subjects(P<0.01), but not in the dialysis patients. According toStudy 3, ANP was unchanged during angiotensin II infusion. Bloodpressure was increased in all groups during noradrenaline andangiotensin II infusions. It can be concluded that ANP is increasedboth in patients with chronic renal failure before requirementof dialysis and in patients on maintenance dialysis. It is suggestedthat noradrenaline stimulates ANP release.     

兔一侧全肺切除术后血浆心钠素变化及意义

目的　探讨心钠素(ANP)与肺切除术后心肺并发症的相关关系。　方法　将30只兔随机分为3组。组Ⅰ12只,行左全肺切除术;组Ⅱ12只,行右全肺切除术;对照组6只,不行肺切除。3组术前、术后测血气分析,ANP,心肌酶和心电图监测,均不吸氧。　结果　组Ⅰ和组Ⅱ术后30分钟pH下降,动脉血氧分压(PaO     

Effects of Atrial Natriuretic Peptide After Prolonged Hypothermic Storage of the Isolated Rat Heart

Primary graft failure (PGF) caused by ischemia‐reperfusion injury (IRI) is the strongest determinant of perioperative mortality after heart transplantation. Atrial natriuretic peptide (ANP) has been found to reduce the IRI of cardiomyocytes and may be beneficial in alleviating PGF after heart transplantation, although there is a lack of evidence to support this issue. The purpose of this study was to investigate the cardioprotective effects of ANP after prolonged hypothermic storage. For this purpose, an isolated working‐heart rat model was used. After the preparation, the hearts were arrested with and stored in an extracellular‐based cardioplegic solution at 3–4°C for 6 h and followed by 25 min of reperfusion. The hearts were divided into four groups (n = 7 in each group) according to the timing of ANP administration: Group 1 (in perfusate before storage), Group 2 (in cardioplegia), Group 3 (in reperfusate), and control (no administration of ANP). Left ventricular functional recovery and the incidence of ventricular fibrillation (VF) were compared. ANP administration at the time of reperfusion improved the percent recovery of left ventricular developed pressure (control, 45.5 ± 10.2; Group 1, 47.4 ± 8.8; Group 2, 45.3 ± 12 vs. Group 3, 76.3 ± 7; P < 0.05) and maximum first derivative of the left ventricular pressure (control, 47.9 ± 8.7; Group 1, 46.7 ± 8.8; Group 2, 49.6 ± 10.8 vs. Group 3, 76.6 ± 7.5; P < 0.05). The incidence of VF after reperfusion did not differ significantly among these four groups (71.4, 85.7, 57.1, and 85.7% in Groups 1, 2, 3, and control, respectively). This result suggests that the administration of ANP at the time of reperfusion may have the potential to decrease the incidence of PGF after heart transplantation.     

Incidence of Arrhythmias and Myocardial Ischaemia During Haemodialysis and Haemofiltration

Thirty-two patients (10 male, 22 female; age 37–82 years)undergoing maintenance haemodialysis or haemofiltration werestudied by means of Holter device capable of simultaneouslyanalysing rhythm and ST changes in three leads. Twenty-fivepatients were on haemodialysis, seven on haemofiltration, meanduration of haemodialysis/haemofiltration being 3.4±3years. Incidence of ventricular tachycardia was low, being detectedonly in 1 of 32 patients. Ventricular premature beats in excessof 10/h during a period of 2 h were found in 8 of 32 patientsand 100 supraventricular premature beats for 2 h or more in4 of 32 patients. Both ventricular premature beats and supraventricularpremature beats were most frequently recorded during the lasthour of haemodialysis/haemofiltration. ECG signs of ischaemiawere detected in eight patients, four of whom were asymptomatic.Ischaemia also occurred predominantly during the last hour ofhaemodialysis/haemofiltration. Two symptomatic patients displayedneither arrhythmias nor ST-changes while being monitored. Thestudy shows that silent ischaemia and arrhythmias in patientsunder going chronic haemodialysis/haemofiltration may not beinfrequent. Recognition of these events could be of importancein the management of these patients.     

Plasma Concentrations of Atrial Natriuretic Peptide in Relation to Body Fluid Status in Chronic Uraemia

Basal plasma -human natriuretic peptide (-hANP) values werefound to be significantly higher in 7 fluid-overloaded chronicdialysis patients than in 13 non-dialysed renal patients withoutextracellular fluid (ECF) expansion. Iso-osmotic reduction ofthe body weight by a single 3-h ultrafiltration caused -hANPto decrease significantly in all anuric patients to values comparableto those of non-dialysed subjects. In this latter group, however,there was a significant inverse relationship between -hANP andglomerular filtration rate but not between -hANP and total bloodvolume. These findings suggest that both ECF expansion and impairedrenal removal of -hANP might be responsible for the high -hANPin chronic uraemia.     

心脏手术病人心肌组织心钠素含量的测定

为探讨心脏手术病人心肌组织心钠素含量变化与心脏病的关系。应用放射免疫分析方法对３７例心脏手术病人心肌组织心钠素的含量进行测定。结果风湿性心脏病病人心肌组织心钠素含量明显高于先天性房、室间隔缺损者。证实心功能不同，心肌组织心钠素含量不同，在病理状态下，心室亦分泌心钠素。     

Significance of Serum Atrial and Brain Natriuretic Peptide Release After Coronary Artery Bypass Grafting

Purpose. The aim of this study was to examine whether serial changes in endogenous levels of brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) were associated with clinical status after coronary artery bypass grafting (CABG).Methods. Serial blood samples were collected from 14 patients preoperatively, 2, 5 and 8h after cardiopulmonary bypass, then up to 7 days postoperatively. Follow-up was done 2 years later.Results. We found a significant increase from the preoperative values in ANP and BNP concentrations on postoperative days 1 and 3 (P 0.001). The elevated BNP concentration correlated with the preoperative values (r² = 0.824, P = 0.0005). Retrospectively, the BNP concentrations after surgery in the patients who suffered cardiac events within 2 years were significantly higher than those in the patients free of cardiac events (P = 0.0023).Conclusion. The BNP concentration after CABG was found to be corrected with interim clinical status after surgery. Thus, it may be necessary for patients with a high postoperative BNP concentration to be closely monitored for coronary events.     

氯胺酮、安氟醚麻醉对子宫切除术患者血浆心钠素、肾素、血管紧张素和醛固酮的影响

本文研究了氯胺酮、安氟醚麻醉对子宫肌瘤切除术患者血浆心钠素(ANP)、肾素(PRA)、血管紧张素(AⅡ)和醛固酮(AL)水平的影响。通过15例子宫肌瘤切除术患者的临床观察,结果表明,子宫肌瘤手术患者氯胺酮、安氟醚麻醉后10min、30min、1h和术毕ANP显著高于麻醉前(P<0.05);PRA与麻醉前比较有升高趋势;AⅡ在麻醉后30min至术毕显著低于麻醉前(P<0.05);血浆AL自麻醉后10min开始升高,至麻醉后1h和术毕非常显著升高(P<0.01)。本文还讨论了它们之间的相互关系。     

高渗氯化钠对心钠素及内源性洋地黄样物质的影响

比较３０例硬膜外阻滞择期手术病人，输入７．５％ＨＳ和５％ＧＳ后血浆ＡＮＰ、ＥＤＬＳ及血流动力学的变化。输入ＨＳ后ＡＮＰ明显升高，ＥＤＬＳ短暂降低，６０ｍｉｎ完全恢复，主动脉顺应性快速增加。输入ＧＳ后ＡＮＰ有增加趋势，但无统计学意义。ＥＤＬＳ显著降低，６０ｍｉｎ时仅为基础值的。ＴＰＲ持续增加，ＣＯ和ＳＶ短暂降低，并伴有血压明显下降。揭示ＨＳ可明显刺激ＡＮＰ分泌，减缓ＥＤＬＳ变化。     

Laboratory Study Atrial Natriuretic Peptide Inhibits Mesangial Cell Proliferation Induced by Early Postnephrectomy Serum

Rat kidney mesangial or tubular cells were grown in tissue culture medium supplemented with sera of 20 sham-operated vs. 20 nephrectomized Charles River rats. Each cell sample was grown with or without addition of atrial natriuretic peptide (ANP) to the medium. ANP completely abolished the growth stimulatory effect of postnephrectomy serum [i.e., effect of renotropic factor(s) present in the serum] on mesangium cells. Tubular cell proliferation was unchanged. We propose that interaction between renotropin and atrial natriutetic peptide activity might be one of the possible mechanisms regulating compensatory renal growth following nephrectomy.     

{beta}2-Microglobulin Kinetics During Haemodialysis and Haemofiltration

Since the identification of ß₂-microglobulin as amajor component of ‘dialysis amyloid’, concern aboutits removal by different dialysis methods has been raised. Haemodialysiswith regenerated cellulose membranes increases serum ß₂-microglobulinby 10–15%. Serial measurements show a very early increaseduring cuprophan haemodialysis, the mechanism of which is asyet unknown. After cuprophan haemodialysis, serum values returnto the initial pretreatment concentrations by the time of thenext haemodialysis. In contrast to regenerated cellulose, dialysiswith polycarbonate lowers serum ß₂-microglobulin by8%, and dialysis with polysulphone by 53%. As opposed to cuprophan,after polysulphone haemodialysis the serum concentrations havenot returned to the initial pretreatment levels within 48 h.Comparison of ß₂-microglobulin removal using the samepolysulphone membrane for haemodialysis and haemofiltrationshows that ß₂-microglobulin is more effectively removedby convection than by diffusion when both treatment modes arematched for blood flow and urea clearance. Therefore, in contrast to haemodialysis with regenerated cellulosemembranes, where a transient, intradialytic release of ß₂-microglobulinis induced, significant removal is observed using, higher permeablemembranes. These findings may have implications for the generationof ‘dialysis amyloid’.     

Water Immersion Induced Alterations of Atrial Natriuretic Peptide in Patients with Non-Inflammatory Acute Renal Failure

Water immersion induced alterations of plasma atrial natriureticpeptide (ANP), circulating plasma volume (PV), plasma sodiumand potassium and mean blood pressure (MAP) were examined in12 patients with non-inflammatory acute renal failure (ARF)and in 15 healthy subjecs. In patients with ARF a significantlyelevated basal ANP (139±13 pg/ml versus 75±4 pg/mlin normals) and elevated MAP (112±3.5 mmHg versus 87±2mmHg in normals) were found. Water immersion induced a significantincrease in plasma ANP in both groups, which was significantlymore marked in healthy subjects (152±13 pg/ml) than inpatients with ARF (86±13 pg/ml). Water immersion wasaccompanied by a significantly more marked reduction of MAP(23±3 mmHg) and plasma sodium (6.1±0.6 mmol/l)in patients with ARF than in normals(12.7±1.5 mmHg and4.2±0.1 mmol/l respectively). In contrast to healthysubjects, in patients with ARF water immersion did not induceenhanced diuresis. In patients with ARF a significantly moremarked increase in plasma volume was found than in normals.Data obtained in this study seem to prove preservation of thephysiological regulatory mechanism of ANP secretion in ARF patientsbut reduction of ANP release induced by central volume expansion.The importance of elevated basal plasma values in the maintenanceof ARF has not been proven.     

Atrial natriuretic peptide in renal development

Although discovered little more than a decade ago, atrial natriuretic peptide (ANP) has been shown to play a significant role in the maintenance of sodium homeostasis. Immediately after birth, plasma ANP concentration is very high concurrent with right atrial dilatation and a high urinary excretion of cyclic GMP (cGMP), the second messenger for ANP. Following postnatal diuresis and natriuresis, atrial volume, plasma ANP concentration, and urinary cGMP excretion decrease to baseline levels. In the ensuling suckling period, the diuretic and natriuretic response to acute saline volume expansion are attenuated, an effect which is offset by the lower hematocrit at this age. Increase in hematocrit by isovolemic exchange transfusion results in a greater rise of plasma ANP concentration following volume expansion, but a reduced excretion of cGMP. Intravenous infusion of ANP results in greater plasma ANP concentration, and greater urinary excretion of cGMP and sodium, in adult than in young rats. This increased metabolic clearance of ANP during early development is due at least in part to increased activity of clearance receptors. In addition, neutral endopeptidase contributes to removal of circulating ANP in maturing as well as adult rats. Infusion of ANP in neonatal or adult rats results in accumulation of cGMP in glomerular podocytes, with a higher threshold for activation in immature animals. Despite the similar response of intracellular generation of cGMP following exposure to ANP in neonatal and adult rats, egression of ANP out of glomeruli is low in neonates, an effect that is due to immaturity of an organic acid transporter. It is possible that these maturational differences in the processing of cGMP account for the developmental changes in renal response to ANP or to acute volume expansion.     

心房肽分泌异常与颈髓损伤后低钠血症

目的 :探讨心房肽 (AtrialNatriureticPeptide ,ANP)分泌异常与颈髓损伤 (CervicalSpinalCordInjury ,CSCI)后低钠血症的关系。方法 :用放免法研究了 15例CSCI并低钠血症患者血浆ANP ,与 2 3例CSCI不伴低钠血症患者及12例正常同龄组的ANP进行比较。并检测血钠和部分患者的尿钠及尿量。结果 :( 1)CSCI伴低钠血症者 ,其血浆ANP水平较不伴低钠血症者及正常对照组显著升高 (P <0 .0 1)。 ( 2 )CSCI急性期血浆ANP水平与CSCI程度密切相关 ,CSCI越重 ,ANP水平越高 ;ANP水平越高 ,血钠越低 ,二者呈负相关 (r =-0 .85 ,P <0 .0 1)。结论 :CSCI后低钠血症患者ANP分泌明显异常 ,ANP分泌增加可能是导致CSCI后低钠血症的一个重要因素。纠正缺氧可能降低ANP水平 ,从而纠正CSCI后顽固性低钠血症。     

Efficacy of Continuous Low-Dose Human Atrial Natriuretic Peptide Given from the Beginning of Cardiopulmonary Bypass for Thoracic Aortic Surgery

Purpose Cardiac surgery performed under cardiopulmonary bypass (CPB) causes abnormalities of the renin-angiotensin-aldosterone system, resulting in decreased urine output and an accumulation of water in the third space. We studied the efficacy of continuous low-dose human atrial natriuretic peptide (hANP) in patients undergoing thoracic aortic surgery. Methods We divided 40 patients undergoing thoracic aortic surgery into two groups: the hANP group, which received 0.02 μg/kg per minute of hANP and the non-hANP group, which did not. The hemodynamics, urine output, intensive care unit (ICU) and hospital stay, bleeding volume, homologous blood transfusion volume, furosemide dose, corrected KCl volume, and postoperative respiratory, hepatic, and renal function were compared in the two groups. Results The urine output during CPB and from CPB weaning to return to ICU was significantly better in the hANP group. The bleeding volume, homologous blood transfusion volume, furosemide dose, and corrected KCl volume were all significantly less in the hANP group. Conclusions These findings support the consensus that hANP exerts its diuretic effects to their full potential when administered continuously at low doses during thoracic aortic surgery. We found it to be effective for postoperative hemostasis and for preventing ischemic reperfusion injury.     

推拿对伴有心血管症状的颈椎病患者血浆心钠素水平的影响

目的 :观察伴有心血管症状的颈椎病患者血浆心钠素 (ANP)水平在推拿前后的变化。方法 :采用放射免疫的方法检测 30例正常人血浆心钠素 ,5 8例观察者推拿前后的血浆心钠素含量。结果 :对照组血浆心钠素含量为 1.2 73± 0 .2 96 ng/m l,观察组推拿前为 1.6 44± 0 .30 2 ng/m l,推拿后为1.373± 0 .372 ng/ml。观察组推拿前血浆心钠素含量明显高于推拿后及对照组 ,且差异有显著性。结论 :提示血浆心钠素参与伴有心血管症状的颈椎病的病理生理变化。推拿可以调整机体植物神经系统功能