Plasma Atrial Natriuretic Peptide (ANP) Concentration in Patients with Pheochromocytoma

The interaction between catecholamines (CA) and ANP is not clearly established. The effects of excess endogenous CA on ANP secretion can be investigated in patients with pheochromocytoma. We studied 27 patients with surgically and histologically proven pheochromocytoma (P) aged 19-70 years. In 16 of these patients plasma ANP study was repeated after surgical removal of the tumour. The control group (C) consisted of 20 healthy volunteers aged 21-48 years. Moreover, 42 patients with uncomplicated mild to moderate essential hypertension (EH) aged 18-48 years were also studied. In P higher plasma ANP concentration versus C, EH was found (51.9 ± 8.1; 25.5 ± 1.5; 19.3 ± 1.5 fmol/ml, respectively). In 16 patients with P, increased plasma ANP level (mean 63.3 ± 12.6 fmol/ml) declined after surgical removal of the tumour (mean 22.4 ± 2.9 fmol/ml). In the P patients no relationship was found between plasma ANP and hormonal patterns of the tumour or between plasma ANP and plasma catecholamines, whereas significant positive correlations between plasma ANP and both systolic and diastolic blood pressure and heart rate were demonstrated. These results suggest that excess CA produced by the chromaffin tumour induce ANP secretion via stimulation of adrenergic receptors. However, influence of the haemodynamic changes evoked by CA cannot be excluded. It is suggested that increased secretion of ANP may be of some importance in maintaining blood pressure homeostasis in patients with pheochromocytoma.     

Effects of Atrial Natriuretic Factor Infusion on Plasma Prorenin Levels in Hypertensive Males

To evaluate the influence of atrial natriuretic factor (ANF) infusion on circulating prorenin, 20 essential hypertensive males, aged between 40 and 60 years, were studied. After 2 weeks under normal sodium intake (120 mmol NaCl per day), patients were randomly assigned to receive either ANF (0.01 fmol/Kg/min) (n.12 patients) or its vehicle (50 mL of isotonic Saline) (n.8 patients) over a period of 60 minutes. Blood samples for plasma renin activity (PRA), prorenin and aldosterone (PAC) were taken at time -60, 0, 20, 40, 60, 120, 180, 240 minutes (infusion time: from 0 to 60 minutes). PRA and PAC decreased during the ANF infusion (PRA: from 0.33±0.05 ng/L/s at time 0 to 0.10±0.06 ng/L/s at 60 minutes, p<0.0001; PAC: from 389.2±99.8 pmol/L at time 0 to 148.7±44.3 pmol/L at 60 minutes, p<0.0001), while returned immediately to baseline levels after the infusion was stopped (PRA: 0.37±0.11 ng/L/s at 180 minutes, PAC: 251.6±72.1 pmol/L at time 180 minutes). On the contrary, plasma prorenin increased during ANF infusion (from 1.66±0.58 ng/L/s at time 0 to 2.44±0.72 ng/L/s at 60 minutes, p<0.05), and returned to baseline levels after the end of the infusion (1.86±0.83 ng/L/s at 180 minutes). These data indicate that ANF infusion may alter only the circulating levels of active renin, without affecting plasma prorenin secretion.     

肝硬化顽固性腹水病人血浆心钠素水平变化

作者应用放免方法测定8例肝硬化顽固性腹水病人血浆心钠素水平变化,并对心钠素水平与尿钠关系进行初步分析。结果表明,①肝硬化顽固性腹水组(RA)血浆心钠素水平(99±48pg/ml)与正常对照组(102±40pg/ml)比较虽无明显差异(q=0.2,P>0.05),但较肝硬化非顽固性腹水组(NRA,176±32pg/ml)已有显著降低(q=5.1,P<0.01)。②NRA组尿钠与血浆心钠素水平呈明显正相关(r=0.67,P<0.05),但于RA组则否,二者无明显相关(r=-0.11,P>0.05)。提示,肝硬化晚期血浆心钠素水平降低及利钠效应衰败可能系顽固性腹水形成的一个重要因素。     

血浆脑利钠肽与房颤病人复律和复发的临床研究

目的研究阵发性或持续性房颤(Af)病人转复窦性心律时,血浆脑利钠肽(BNP)水平及其临床意义。方法选取62例心功能(1~3)级病人,采用放免法测定房颤及窦性心律时病人血浆中BNP的浓度,观察两组BNP水平、房颤发作次数。结果病人房颤发生时BNP浓度为(88.36±22.32)pg/mL,比复律后窦性心律时(57.48±20.32)pg/mL明显增高(P<0.05),高BNP水平病人组房颤发生次数较低BNP水平病人多。多因素分析显示血浆BNP水平与Af持续时间是转律后窦性心律维持的独立影响因子。结论血BNP浓度增高是发生心房颤动的预告因子,高水平的BNP更容易复发房颤,血浆BNP水平低或Af持续时间短者转律后窦性心律较易维持。     

Plasma Concentrations of Atrial Natriuretic Factor and Hemodynamics in Pregnancy-Induced Hypertension

Plasma values of atrial natriuretic factor (ANF) were evaluated in 31 women with pregnancy-induced hypertension (PIH) and 31 normal pregnant women at the same age of gestation. In 27 women with PIH and 27 normal pregnant women forearm venous tone (FVT) was evaluated by Strain Gauge Plethysmography. Forearm vascular resistance (FVR) was measured as the ratio of mean blood pressure (MBP) to forearm blood flow. In addition Cardiac Index (CI) by means of transthoracic electrical bioimpedance and total peripheral vascular resistance (TPR) (with the Frank Equation) were also measured. In comparison with the normal pregnant women, the women with PIH had similar values of hematocrit (as an index of plasma volume) and significantly higher levels of FVR and TPR, while ANF plasma values did not differ significantly. Subdividing the women with PIH in relation to the presence of proteinuria (20.3 g/l), those with proteinuria, in addition to significantly higher levels of FVR and TPR, had significantly higher levels of FVT than normal pregnant women, while ANF plasma values were higher even though the difference was only near the level of significance. Hypertensive women with proteinuria also had higher values of FVT than hypertensive women without proteinuria. By means of multiple regression ANF did not show any significant correlations with hematocrit or sodium excretion. Hypertension with proteinuria seems to represent a more severe form of the disease in which, in addition to the probable influence of other factors such as the renin-angiotensin and prostaglandin systems, a greater increase in peripheral sympathetic tone than in hypertension alone appears to be present, causing a reduction in venous compliance in addition to the elevation in FVR and TPR, with increase in central blood volume and atrial stretch. This may explain the higher ANF plasma levels in these patients in comparison with normal pregnant women, even though the absence of a significant correlation of ANF with hematocrit and the fact that ANF increase was only near the level of significance may suggest a change in the relation between ANF secretion and atrial volume receptors in pregnancy either normal or complicated by hypertension. ANF does not seem to play an important role in water and sodium excretion in PIH probably because of the presence of very high plasma levels of hormones such as aldosterone, progesterone and oestriol which, together with renal prostaglandins, seem to be involved in diuresis and natriuresis in pregnancy.     

Increased Plasma Levels of Atrial Natriuretic Peptide (ANP) in Patients with Paroxysmal Supraventricular Tachyarrhythmias

ABSTRACT. Nilsson G, Pettersson A, Hedner J, Hedner T (Department of Internal Medicine, Central Hospital, Halmstad and Department of Clinical Pharmacology, Sahlgrenska University Hospital, Göteborg, Sweden). Increased plasma levels of atrial natriuretic peptide (ANP) in patients with paroxysmal supraventricular tachyarrhythmias. Acta MedScand 1987; 221:15–21. Atrial natriuretic peptide (ANP) is a cardiac hormone originating from atrial cardiocytes. It seems to be involved in the regulatory control of circulating volume and vascular tone. Plasma immunoreactive atrial natriuretic peptide (IrANP) was investigated in 22 patients with paroxysmal supraventricular tachyarrhythmia (16 with atrial fibrillation, 4 with atrial flutter, one with a Wolf-Parkinson-White syndrome (WPW) and one with atrial tachycardia). During the aute attack, IrANP was significantly increased (125.3± 11.4 pmol/1) compared to samples obtained during convalescence (55.9±4.7 pmol/1). Heart rate (HR) was 144±4.3 beats/min during the arrhythmia and 75±2.6 during convalescence. The reduction of IrANP in plasma from the acute attack of tachycardia to follow-up was significantly related to the reduction of HR (p<0.05). Irrespective of type of paroxysmal supraventricular tachyarrhythmia, 50% of the patients experienced polyuria during the attack. This symptom was more frequent in younger patients with a shorter duration of tachycardia. Polyuria patients had a higher HR during the attack of supraventricular tachycardia. Even though polyuria was not alwavs found in the patients with the highest IrANP values, the symptom was associated with significantly higher concentrations of Ir ANP in plasma compared to the non-polyuria group. We conclude that Ir ANP is increased in plasma during acute attacks of paroxysmal supraventricular tachycardia. Furthermore, the polyuria frequently associated with this condition may partly be due to excess release of ANP from cardiac myocytes.     

Changes of Dopamine and Atrial Natriuretic Factor by Mild Exercise for Hypertensives

Changes of humoral factors related to the regulation of fluid volume were investigated in exercise training for hypertensives. Twelve patients with essential hypertension were treated with an aerobic exercise for 10 weeks. A significant reduction in blood pressure from 161±3/100±2 mmHg at week 0 to 142±5/94±3 mmHg at week 4 was observed which continued until week 10. Urine dopamine was increased significantly at the 4th week from 386±29.4 μg/day at week 0 to 524±46.3 μg/day and plasma atrial natriuretic factor (ANF) was significantly reduced at the 4th week, from 41.5±2.7 pg/ml at week 0 to 32.6±3.7 pg/ml. Plasma volume was found reduced significantly from 2,531±166 ml/m² at week 0 to 2,221±165 ml/m² at week 10. These results suggest that the increase of dopamine and reduction of plasma ANF which took place at the early stage might be related to, at least in part, the depletion of plasma volume and the reduction of blood pressure in mild exercise for hypertensives.     

Changes in Plasma Atrial Natriuretic Peptide during Exercise in Healthy Volunteers

ABSTRACT. Thamsborg G, Storm T, Keller N, Sykulski R, Larsen J (Departments of Clinical Chemistry and Internal Medicine, Sundby Hospital, Copenhagen, and Department of Cardiology, Hvidovre Hospital, Hvidovre, Denmark). Changes in plasma atrial natriuretic peptide during exercise in healthy volunteers. Acta Med Scand 1987; 221:441–4. Graded exercise was performed in three healthy volunteers. Plasma levels of immunoreactive atrial natriuretic peptide (iANP) were determined at different workloads. Unchanged or slightly decreased plasma levels of iANP were observed during light exercise, whereas at medium to high workloads a considerable increase in plasma levels of iANP was found. Factors responsible for the increase in plasma levels of iANP might include elevated right atrial pressure and increased plasma levels of epinephrine and norepinephrine.     

Effect of Posture on the Plasma Levels of Atrial Natriuretic Factor

Atrial natriuretic factor (ANF) is a peptide with potent natriuretic, diuretic and vasorelaxant activities. Stretching of the right atria causes release of ANF into the circulation. Therefore, changes in central blood volume or acute volume expansion are likely to change the plasma levels of ANF. In this study we investigated the effects of changes in posture on the plasma levels of ANF, plasma renin activity (PRA) and plasma aldosterone (aldo). Eight male and five female volunteers ranging in age from 23 to 26 years were placed on a normal sodium intake and on the experimental day blood was obtained for ANF, PRA, and aldo after 30 minutes of lying supine, 30 minutes of 10 or 20 degrees head-down tilt, and 30 minutes of standing. Plasma ANF increased significantly after 30 minutes of head-down tilt from the supine value of 33.7 ± 5.2 pg/ml to 47.7 ± 7.7 pg/ml (p<0.02) and suppressed to 14.1 ± 0.02) after 30 minutes of standing. PRA did not change significantly with head-down tilt, (supine 1.64 ± 0.44 ngAI/ml/h vs. 30 minutes tilt 1.28 ± 0.32 ngAI/ml/h (p = NS). Plasma aldosterone decreased by head-down tilt from 11.2 ± 1.2 ng/ml to 8.4 ± 0.8 ng/dl (p<0.02) and returned to the supine level after standing. In conclusion ANF levels change significantly with posture. Increase in central blood volume by head-down tilt increases ANF levels and suppresses plasma aldosterone with no effect on PRA. Standing decreases ANF significantly. These results suggest that for proper interpretation of plasma levels of ANF, posture at the time of sampling has to be standardized.     

肾血管性高血压大鼠心脏肥厚不同时期血浆及组织心钠素、内皮素含量变化

目的 了解高血压心脏病左室结构、功能变化时血浆及心肌组织中心钠素(atrial natriuretic peptide ANP)、内皮素(endothelin ET)含量变化。方法 应用放免法监测二肾一夹意义型(2K1C)肾血管性高血压大鼠(RHR)血浆及心肌组织中ANP、ET含量变化，并根据超声心动图评价高血压大鼠心脏结构、功能动态变化，将高血压大鼠进行分组。结果 高血压左室向心性肥厚期血浆及心肌组织(左心室)中ANP、ET含量明显升高；左室离心性肥厚期血浆ET较向心性肥厚期组更高，但心肌组织中ET含量与其无显著差别，而血浆及心肌组织中．ANP含量均较向心性肥厚期组低。结论 2K1C型高血压大鼠血浆及心肌组织中ANP、ET含量均升高；血浆ET与．ANP含量变化在左室肥厚中可能起着更为重要作用。     

盐敏感性高血压病患者血浆心钠素、血管紧张素Ⅱ和醛固酮水平测定及苯那普利治疗的初步观察

目的探讨心钠素(ANP)和肾素-血管紧张素-醛固酮系统(RAAS)在盐敏感性高血压病发病中的作用及苯那普利的降压作用和ANP的关系.方法采用改良的Sullivan急性口服盐水负荷试验的方法将64例高血压病患者分为盐敏感性(SS, 30例)和非盐敏感性(NSS,34例)高血压病组,测定盐负荷前与盐负荷期间血浆ANP、血管紧张素Ⅱ(AⅡ)和醛固酮(ALD)水平.30例正常人为对照组.SS组患者采用自身对照的方法予以口服安慰剂和苯那普利(10 mg/d～20 mg/d),观察治疗前后血压及血浆ANP水平的变化.结果 (1)基础血浆ANP水平,SS组显著低于NSS组,NSS组显著低于正常组[分别为SS(110.28±15.40)pmol/L,NSS(145.52±26.53)pmol/L和对照组(197.74±26.20)pmol/L, P均<0.01].盐负荷期SS组和NSS组血浆ANP水平均明显增高[分别为(133.56±34.03)pmol/L和(169.20±35.91)pmol/L,P均<0.05].增高的百分数两组间无显著性差异(P>0.05).但SS组血浆ANP仍低于正常水平.(2)基础血浆AⅡ和ALD水平在SS组与NSS组间无明显差异(P均>0.05).盐负荷期SS组和NSS组血浆AⅡ和ALD水平无明显改变(P均>0.05).(3)SS组于苯那普利治疗后血压明显降低(P<0.01),血浆ANP水平显著增高[(146.74±31.86)pmol/L,P<0.01].(4)基础血浆ANP水平与盐负荷引起的平均动脉压增高的幅值呈显著负相关( b=-0.06,P<0.05).结论循环内源性ANP的不足可能是SS高血压病的一个重要发生机制.苯那普利显著升高血浆ANP水平,能够有效降低SS高血压病患者的血压.     

Secretory Patterns of Atrial Natriuretic Factor (ANF) By Culture Cardiocytes of Right and Left Atrium From Newborn and Adult RS

Atrial cardiocytes from newborn (2-5 day old) and adult rats were cultured and the secretory patterns of atrial natriuretic factor (ANF) from isolated right and left atrial cells were investigated by radioimmunoassay. Newborn atrial cardiocytes from the left atrium consistently secreted larger amounts of ANF than those from the right with a peak on the 6th day and a decrease up to the 12th day. In contrast, adult atrial cardiocytes secreted much less ANF and this decreased to very low levels from the 3rd day up to the 12th day in culture although ANF was present in measurable amounts in these cells.     

血浆、腹水中心钠素、加压素的测定及意义

本文采用放射免疫分析法测定25例肝硬化腹水患者血浆、腹水中心钠素和加压素的水平，发现血浆，腹水中心钠素水平相当，均明显高于正常血浆水平；血浆加压素升高不明显，而腹水中加压素浓度显著高于血浆。结果提示心钠素和加压素的分泌释放异常，在肝硬化钠，水潴留及腹水形成中有一定的作用。腹水中高浓度的心钠素和加压素通过腹水回输可能起到一定的治疗作用。     

VVI起搏术后心房颤动与心钠素和室房逆传的关系

长期心脏起搏的患者,有部分并发心房颤动,尤其是VVI起搏者。本文主要阐述VVI起搏术后心房颤动与血心钠素和室房逆传的关系,为选择适当的起搏器和起搏方式以及临床干预措施提供理论依据,从而减少起搏术后心房颤动的发生。     

硝苯地平和卡托普利对高血压患者血浆、唾液、尿液心钠素浓度的影响

目的探讨心钠素（ＡＮＰ）在高血压发病中的作用。方法５２例原发性高血压（ＥＨ）患者，随机分组，应用硝苯地平或卡托普利治疗２周前后，测定血浆、唾液、尿液ＡＮＰ含量的变化，并与健康组对照。结果治疗前患者血浆、唾液、尿液中ＡＮＰ均高于对照组（Ｐ＜０．０１）。治疗２周后，高血压组ＳＢＰ、ＤＢＰ和血、唾液、尿液中ＡＮＰ较治疗前明显降低（Ｐ＜０．０１），而治疗组间比较差异无显著性（Ｐ＞０．０５），且唾液和尿液中ＡＮＰ与血浆中浓度有同样变化趋势。结论硝苯地平和卡托普利可能是通过抑制ＡＮＰ的产生和释放的某个环节而发挥其降压效果的。     

Hemodynamic and Renal Effects of Atrial Natriuretic Factor (99-126) in Volume Expanded Sheep

ABSTRACT

The renal and hemodynamic effects of atrial natriuretic factor 99-126 (ANF) were examined in hypervolemic sheep and the results compared to responses previously observed in normal isovolemic sheep. Infusion of 500ml dextran over 60 min increased blood pressure by 6 ± 2 mmHg, associated with increases in cardiac output and stroke volume. No change was seen in heart rate nor total peripheral resistance. Subsequent infusion of ANF at 100 μg/h for 60 min reduced blood pressure by 6 ± 1 mmHg and decreased stroke volume and cardiac output. There was no change in heart rate. Total peripheral resistance decreased slightly, to a similar degree to that seen after control infusion of 500 ml dextran. Moderate increases in urine volume, sodium and chloride excretion were seen after infusion of dextran and subsequent infusion of ANF markedly enhanced these renal effects. The renal changes produced by ANF in volume expanded sheep were significantly greater than those observed in normal sheep. Although normal sheep are more sensitive to the hemodynamic than to the renal effects of ANF, after dextran pretreatment there was enhancement of the renal responses with little change in the effects on blood pressure.     

内皮素-1和心钠素在脑梗死中的作用研究

目的探讨脑梗死病人血浆内皮素-1(ET-1)和心钠素(ANP)的相互作用及其在脑梗死发病过程中的作用机制和临床意义.方法应用放射免疫分析法测定36例脑梗死病人(治疗组)和33例健康人(对照组)的血浆ET-1和ANP含量.结果治疗组急性期血浆ET-1含量明显高于恢复期和对照组,急性期血浆ANP的含量明显高于恢复期和对照组;脑梗死中度～重度病人血浆ET-1含量明显高于轻度病人;急性期病人血浆ANP含量与ET-1含量呈正相关(P＜0.01).结论 ET-1和ANP均参与了脑梗死的病理生理过程,监测脑梗死病人血浆ET-1水平可作为反映病人病情程度的一项参考指标.     

B型利钠肽与孤立性心房颤动

目的:探讨B型利钠肽(BNP)与孤立性心房颤动(AF)的血栓事件发生、复律及再发之间的关系。方法:103例孤立性AF患者行食道超声(经食道超声心动图)、头颅计算机断层摄影术或磁共振(CT／MRI)检查及血BNP测定。探讨BNP在AF血栓事件及其相关因素中的作用。根据血栓事件将患者分为有血栓事件组(n=15)和无血栓事件组(n=88)。对于有复律指征的患者,根据AF复律及再发情况分为复律不成功患者(复律失败或随访期内再发,n=16)和复律成功患者(复律成功并随访期内维持窦性心律,n=7),分别进行对比研究。结果:服药后无血栓事件组BNP降低幅度优于血栓事件组,有显著性显异(P<0．05)。复律成功患者较复律不成功患者BNP水平低[(60±32)ng／L比(178±70)ng／L,P<0．05]、病程短[(3．0±1．9)个月比(7．6±2．5)个月,P< 0．05]和左心房内径小[(42．3±3．4)mm比(48．6±5．1)mm,P<0．05],均有显著性差异。多因素Logistic回归分析: BNP是预测孤立性AF血栓事件的独立因素(P<0．05);BNP、左心房内径和AF病程是预测AF复律及再发的独立因素(P均<0．05)。结论:BNP可作为预测孤立性AF血栓事件和AF复律与再发的临床指标。     

Plasma Levels of Atrial Natriuretic Peptides in Conscious Adult Spontaneously Hypertensive Rats

The effects of acute volume expansion and acute salt loading on the plasma levels of immunoreactive atrial natriuretic peptides (ir-ANP's) were investigated in conscious adult (16 weeks) Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). Basal plasma concentrations of ir-ANP's were similar (108 ± 9 pg/ml and 105 ± 8 pg/ml, respectively) in hypertensive and normotensive rats. In both strains mean, arterial pressure, heart rate and plasma catecholamines were, unaltered by acute volume expansion but significantly elevated by acute salt loading. However, both acute volume expansion and acute salt loading increased plasma concentrations of ir-ANP's, similarily in SHR and WKY rats, independent of blood pressure or plasma catecholamine levels. Our findings show that chronic hypertension in SHR does not result in changes in basal or VOL- and SAL-stimulated levels of circulating ir-ANP's.