Plasma concentrations of atrial natriuretic peptide in various diseases

Using a radioimmunoassay for atrial natriuretic peptide (ANP) we studied plasma concentrations of immunoreactive ANP in order to investigate the pathophysiological role of ANP in patients with various diseases. Plasma ANP levels were elevated in patients with congestive heart failure (394 +/- 260 pg/ml, n = 8) and chronic renal failure (219 +/- 86 pg/ml, n = 11). In patients undergoing hemodialysis plasma ANP levels were markedly high and decreased after hemodialysis from 433 +/- 166 pg/ml to 204 +/- 92 pg/ml (n = 11). ANP was removed from blood to dialysate (21 +/- 13 pg/ml of dialysate, n = 6, dialysate flow: 500 ml/min). Plasma ANP level was conversely correlated with creatinine clearance (r = -0.812, p less than 0.001) in patients with renal diseases (n = 29). In patients with atrial fibrillation, pace maker implantation, lung disease, chronic glomerulonephritis, nephrotic syndrome, essential hypertension, liver disease and cerebrovascular disease, plasma ANP levels were not significantly different from those in normal subjects (70 +/- 32 pg/ml, n = 28). These results suggest that ANP may be a circulating hormone playing pathophysiological roles in congestive heart failure and chronic renal failure.     

Relationship between atrial natriuretic polypeptide and cyclic 3'5'-guanosine monophosphate in human plasma

To examine the interrelationship between human atrial natriuretic polypeptide (hANP) and cyclic 3'5'-guanosine monophosphate (cyclic GMP), plasma concentrations of these compounds were determined in 61 disease-free humans, as controls, and in 35 patients with congestive heart failure. Levels of plasma hANP (199.6 +/- 53.7 pg/ml) and cyclic GMP (12.6 +/- 1.7 pmol/ml) in patients with congestive heart failure were significantly higher than in the control subjects (hANP 57.1 +/- 2.8 pg/ml, cyclic GMP 5.2 +/- 0.3 pmol/ml). Although plasma hANP concentrations in the patients with congestive heart failure tended to increase with the severity of cardiac dysfunction, there was no significant correlation between the levels of plasma hANP and the grade of heart failure, classified according to the New York Heart Association. However, a significant correlation was found between plasma hANP and cyclic GMP concentrations in both the healthy subjects and the patients with congestive heart failure, and a weak positive correlation between plasma hANP and cyclic 3'5'-adenosine monophosphate (cyclic AMP) concentration in the patients with congestive heart failure. Thus, changes in plasma cyclic GMP concentration depend to some extent on the plasma concentrations of hANP.     

Enhanced urinary excretion of albumin in congestive heart failure: effect of ACE-inhibition.

Urinary excretion of albumin and beta 2-microglobulin were measured in 13 patients with congestive heart failure, NYHA class II-IV, before and after captopril treatment for 4 weeks, and in 13 healthy control subjects. The urinary excretion of albumin was enhanced in heart failure patients compared to control subjects (12.0 micrograms min-1 vs 2.8 micrograms min-1; medians, p less than 0.01), whereas beta 2-microglobulin excretion was normal. No significant change in urinary excretion of albumin was observed after captopril. Using Spearmann's test the urinary excretion of albumin was correlated to the NYHA class (Px = 0.681, p less than 0.05, plasma renin (Px = 0.886, p less than 0.01) and plasma angiotensin II (Px = 0.5840, p less than 0.05). Correlations with atrial natriuretic peptide (rho = 0.412, p = 0.153) and aldosterone (Px = 0.487, p = 0.106) did not reach significance. By multiple linear regression analysis only plasma renin activity was correlated to albumin excretion. In conclusion, patients with congestive heart failure had an increased urinary excretion of albumin. It is suggested that the enhanced transglomerular passage of albumin in congestive heart failure is partly due to an increased intra-renal angiotensin II generation, but elevated plasma level of atrial natriuretic peptide and increased renal venous pressure may also be important pathogenetic factors.     

Brain natriuretic peptides in human plasma, spinal cord and cerebrospinal fluid.

In cases of heart failure, the plasma level of immunoreactive human brain natriuretic peptide (IR-hBNP) measured by radioimmunoassay increased 6- to 46-fold over normal level (4.1 +/- 1.0 pg/ml), depending upon the severity. These levels did not significantly correlate to the levels of IR-human atrial natriuretic peptide in individuals. A 4-kDa IR-hBNP, corresponding to authentic hBNP (1-32), was predominant in normal plasma. In cases of cardiac disease, larger molecules which were assumed to be precursors of the 4-kDa form were accumulated in plasma. IR-hBNP was detected in spinal cords (7-24 pg/mg protein) and cerebrospinal fluid (8-19 pg/ml) of patients with noncardiac diseases. The major molecular form corresponded to the hBNP (1-32).     

Plasma levels of immunoreactive atrial natriuretic factor in healthy subjects and in patients with edema.

Atrial natriuretic factor (ANF), a recently sequenced cardiac peptide, has been shown to have potent natriuretic, diuretic, and vasodilating effects in several species. We have developed a radioimmunoassay to measure the levels of immunoreactive ANF in human plasma. Plasma levels of ANF in healthy volunteers on a low sodium diet were 9.8 +/- 1.4 pmol/liter and increased to 21.9 +/- 3.0 on a high sodium diet. The levels of atrial natriuretic factor correlated directly with urinary sodium and inversely with plasma renin activity and plasma aldosterone levels. Patients with marked edema due to congestive heart failure had plasma levels of atrial natriuretic factor five times higher than normal (P less than 0.05), whereas patients with cirrhosis and edema had levels that were not different from normal. These results suggest that atrial natriuretic factor plays an important role in the adaptation to increased sodium intake.     

血浆NT-proBNP在老年慢性充血性心力衰竭诊断中的价值及其与心功能的关系

目的探讨血浆N端脑利钠肽前体（N-terminal precursor of brain-type natriuretic peptide,NT-proBNP）在老年慢性充血性心力衰竭（chronic congestive heart failure,CHF）诊断中的价值及与心功能的关系。方法选择83例CHF患者和60例健康体检者,采用化学发光免疫分析法检测血浆NT-proBNP水平,超声心动图检测患者心脏结构和功能改变。结果 CHF组血浆NT-proBNP水平（1643.3±756.7 pg/ml）显著高于健康体检者（46.2±11.4 pg/ml）,差异有统计学意义（P〈0.05）;而且,随着病情的进展,血浆NT-proBNP含量逐渐升高（P〈0.05）。结论血浆NT-proBNP水平与CHF患者的心力衰竭程度正相关,在临床CHF病人诊断和分级中具有重要的作用。     

Clearance of brain natriuretic peptide in patients with chronic heart failure: indirect evidence for a neutral endopeptidase mechanism but against an atrial natriuretic peptide clearance receptor mechanism.

1. Brain natriuretic peptide is a new natriuretic hormone with striking similarity to atrial natriuretic peptide, but there are no previous data concerning its clearance in man. Two pathways of clearance for atrial natriuretic peptide are recognized: degradation by neutral endopeptidase and binding to atrial natriuretic peptide clearance receptors. We have examined the effect of candoxatril, an inhibitor of neutral endopeptidase (dose range 10-200 mg), and the effect of an infusion of a pharmacological dose [45 micrograms (90 micrograms in two patients)] of synthetic human atrial natriuretic peptide on plasma human brain natriuretic peptide-like immunoreactivity levels in seven patients with mild to moderate chronic heart failure. 2. Plasma human brain natriuretic peptide-like immunoreactivity levels were elevated in all patients (mean +/- SEM 22.0 +/- 6.2 pmol/l) compared with healthy control subjects (1.3 +/- 0.2 pmol/l, n = 11). 3. In all patients, candoxatril increased both plasma atrial natriuretic peptide (P less than 0.05) and plasma human brain natriuretic peptide-like immunoreactivity (P less than 0.05) levels. 4. By contrast, an exogenous infusion of atrial natriuretic peptide had no effect on plasma human brain natriuretic peptide-like immunoreactivity levels despite increasing the plasma atrial natriuretic peptide concentration to 424 +/- 74 pmol/l, which is a level of atrial natriuretic peptide which would have 'swamped' all atrial natriuretic peptide clearance receptors. 5. We have therefore shown that plasma human brain natriuretic peptide-like immunoreactivity levels in chronic heart failure are increased by a neutral endopeptidase inhibitor, but are unchanged by an exogenous infusion of atrial natriuretic peptide.(ABSTRACT TRUNCATED AT 250 WORDS)     

Beneficial effect of beta-adrenergic blockade on left ventricular function in haemodialysis patients

Congestive heart failure is a common and serious complication in patients undergoing chronic dialysis. However, there have been no studies on preferential medical therapies to improve left ventricular function in haemodialysis patients. Beta-blocker treatment is known to improve left ventricular function in patients with dilated cardiomyopathy; moreover, plasma levels of noradrenaline and natriuretic peptides are sensitive markers of left ventricular dysfunction. The present study investigated whether beta-blocker treatment could improve left ventricular function in haemodialysis patients with a dilated left ventricle. Our study group comprised 14 haemodialysis patients with a dilated left ventricle, who had undergone maintenance haemodialysis for a mean of 11 years. The following haemodynamic parameters were evaluated before and after 4 months of treatment with the beta-blocker metoprolol: left ventricular dimension at end-systole and end-diastole, and fractional shortening. Plasma levels of noradrenaline, atrial natriuretic peptide and brain natriuretic peptide were also determined. Dry body weight and haemoglobin concentration showed no significant change after compared with before treatment with metoprolol. Heart rate decreased significantly, from 79+/-9 beats/min to 69+/-9 beats/min, but systolic blood pressure remained unchanged. The left ventricular dimension both at end-systole and at end-diastole was decreased, and fractional shortening increased significantly. Plasma levels of noradrenaline did not change significantly, but those of atrial natriuretic peptide and brain natriuretic peptide decreased markedly [from 100+/-89 pg/ml to 46+/-29 pg/ml (P=0.0051) and from 549+/-516 pg/ml to 140+/-128 pg/ml (P=0.0035) respectively]. In conclusion, beta-blocker therapy with metoprolol can markedly attenuate left ventricular remodelling and decrease the plasma levels of natriuretic peptides in haemodialysis patients with a dilated left ventricle.     

Natriuretic peptides and the prevalence of congestive heart failure in patients with pacemakers

AIM: The aim of the study was to investigate the diagnostic potential of natriuretic cardiac peptide measurement in the context of left ventricular dysfunction and comorbidities in a pacemaker population. MATERIAL AND METHODS: Ninety-five consecutive patients with pacemakers were included in the study. All patients underwent echocardiography and were asked to complete the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Brain natriuretic peptide (BNP), N-terminal proatrial natriuretic peptide (N-ANP) and atrial natriuretic peptide levels in plasma were measured. RESULTS: Twenty-six percent of patients had reduced systolic left ventricular function; only 16 patients had a history of congestive heart failure. BNP was abnormally elevated in 64%, N-BNP in 72% and N-ANP in 96% of patients. Both BNP (r = 0.30; P < 0.01) and N-ANP (r = 0.39; P < 0.0005) correlated with MLHFQ. The strongest correlation was found between N-ANP and the ejection fraction (r = 0.6; P < 0.0001). Patients were stratified in a high-risk group and a low risk-group according to their N-ANP (N-ANP > 5000 fmol L(-1); n = 63 and N-ANP < 5000 fmol L(-1), n = 32) and BNP levels (BNP > 400 pg mL(-1); n = 17 and BNP < 400 pg mL(-1), n = 78). N-ANP was correlated with hypertension (P < 0.003) and atrial fibrillation (P < 0.03), and BNP with mitral insufficiency (P < 0.002). CONCLUSIONS: Cardiac natriuretic peptides are markedly elevated in the majority of patients with pacemakers. The prognostic significance of BNP and N-ANP in left ventricular dysfunction warrants close follow-up schedules.     

血浆BNP检测对心力衰竭患者心功能分级评价中的作用

目的探讨血浆B型钠尿肽(B-type natriuretic peptide,BNP)浓度在诊断慢性心力衰竭(chronic heart fail-ure,CHF)及心功能分级评价中的作用。方法采用化学发光微粒子酶免疫分析法测定89例CHF患者及40名健康对照者血浆BNP浓度。依据美国纽约心脏病协会(New York Heart Association,NYHA)分级方案对CHF患者进行心功能分级。结果血浆BNP诊断CHF临界值为111.7pg/ml,灵敏度88.16%,特异性94.29%;CHF组血浆BNP浓度为574.3±176.2pg/ml,明显高于对照组66.7±17.5pg/ml,P<0.05。CHF患者NYHA心功能Ⅰ级到Ⅳ级血浆BNP逐渐升高,各级之间BNP浓度比较,P<0.05;血浆BNP水平与NYHA分级间存在明显的正相关,r=0.835,P<0.001。各级NYHA分级CHF患者经治疗后血浆BNP水平显著下降,与治疗前相比,P<0.05。结论 CHF患者血浆BNP水平随着心力衰竭严重程度的增加而升高,血浆BNP可以准确评价心功能,可作为临床诊断、疗效观察以及预后判断CHF的客观指标。     

An experimental study of cardiac natriuretic peptides as markers of development of congestive heart failure

The use of cardiac peptide measurements as possible diagnostic tools in congestive heart failure has been extensively discussed in the recent literature. Therefore, the aim of this study was to establish a model of experimental chronic heart failure, and thereby perform a comparative study of secretion and circulating levels of the cardiac peptides atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide (N-terminal proANP) and brain natriuretic peptide (BNP) during evolving heart failure. Chronic heart failure was induced in seven pigs by rapid left atrial pacing for three weeks. The effects of failure induction were documented 24 h after pacemaker deactivation. Hemodynamic indices of cardiac preload, like pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP), were all considerably increased compared to sham operated controls. Likewise, plasma endothelin-1, noradrenaline, renin activity, aldosterone and angiotensin II were all markedly increased. Heart failure was accompanied by significant increases in both estimated cardiac secretory rate and plasma concentrations of all three cardiac peptides, significantly correlated to the PCWP. The directional changes during evolving heart failure were similar, although the percentage increase in plasma BNP was much larger than for ANP and N-terminal proANP. In absolute molar terms, however, the BNP concentration changes were minor compared to those of the other two peptides. The larger percentage increase of BNP might indicate its superiority as a marker of heart failure development, provided a functional assay suitable for clinical use can be designed for a peptide circulating in this low concentration range.     

Atrial natriuretic factor and changes in dietary sodium intake in patients with chronic renal failure

1. In order to examine the potential role of atrial natriuretic factor in modulating the increased sodium excretion per nephron in chronic renal failure, we studied 12 uraemic patients on the last day of two successive 7 day periods during which their sodium intake was 100 and 20 mmol of sodium/day, respectively. 2. There was a parallel decrease from 6.31 +/- 0.75 to 2.17 +/- 0.32% in the fractional excretion of filtered sodium and from 234.4 +/- 74.9 to 80.6 +/- 20.3 pg/ml (supine position) or 140.1 +/- 43.6 to 60.7 +/- 14.6 pg/ml (upright position) in plasma atrial natriuretic factor. Both parameters were significantly correlated during the two periods of different sodium intake (P less than 0.05). The ratio of plasma guanosine 3':5'-cyclic monophosphate to plasma creatinine changed proportionally to plasma atrial natriuretic factor. Plasma aldosterone and plasma renin activity increased during the sodium-depleted period but only plasma renin activity was significantly correlated with fractional excretion of filtered sodium. 3. The predominant role of atrial natriuretic factor compared with that of aldosterone in the renal response to varying sodium intake is suggested both by regression analysis and by the effect of 5 day's treatment with a converting enzyme inhibitor (enalapril) in six other uraemic patients on a normal (100 mmol/day) sodium intake. Such treatment, although resulting in a significant increase in plasma renin activity and a significant decrease in plasma aldosterone, at least in the supine position, did not modify the fractional excretion of sodium and plasma atrial natriuretic factor.(ABSTRACT TRUNCATED AT 250 WORDS)     

Circulating natriuretic peptide concentrations in patients with end-stage renal disease: role of brain natriuretic peptide as a biomarker for ventricular remodeling.

OBJECTIVES: To determine levels of natriuretic peptides (NPs) in patients with end-stage renal disease (ESRD) and to examine the relationship of these cardiovascular peptides to left ventricular hypertrophy (LVH) and to cardiac mortality. PATIENTS AND METHODS: One hundred twelve dialysis patients without clinical evidence of congestive heart failure underwent plasma measurement of NP concentrations and echocardiographic investigation for left ventricular mass index (LVMI). RESULTS: Plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations correlated positively with LVMI and inversely with left ventricular ejection fraction, whereas C-type NP and Dendroaspis NP levels did not correlate with LVMI. In dialysis patients with LVH (LVMI >125 g/m2), plasma ANP and BNP concentrations were increased compared with those in dialysis patients without LVH (both P<001). In a subset of 15 dialysis patients without LVH or other concomitant diseases, plasma BNP concentrations were not significantly increased compared with those in 35 controls (mean +/- SD, 20.1+/-13.4 vs 13.5+/-9.6 pg/mL; P=.06), demonstrating that the BNP concentration was not increased by renal dysfunction alone. Furthermore, the BNP level was significantly higher in the 16 patients who died from cardiovascular causes compared with survivors (mean +/- SD, 129+/-13 vs 57+/-7 pg/mL; P<.003) and was significantly associated with greater risk of cardiovascular death in Cox regression analysis (P<.001), as was the ANP level (P=.002). CONCLUSIONS: Elevation of the plasma BNP concentration is more specifically related to LVH compared with the other NP levels in patients with ESRD independent of congestive heart failure. Thus, BNP serves as an important plasma biomarker for ventricular hypertrophy in dialysis patients with ESRD.     

B-type natriuretic peptide: a diagnostic, prognostic, and therapeutic tool in heart failure.

B-type natriuretic peptide is a neurohormone secreted from the cardiac ventricles in response to ventricular stretch and pressure overload. It counteracts the vasoconstriction that occurs as a compensatory mechanism in heart failure. A new test for measuring plasma levels of B-type natriuretic peptide can help in the diagnosis and treatment of patients with congestive heart failure. Dyspnea associated with cardiac dysfunction is highly unlikely in patients with levels of the peptide less than 100 pg/mL. Whereas most patients with significant congestive heart failure have levels of the peptide greater than 400 pg/mL, in patients with levels of 100 to 400 pg/mL, left ventricular dysfunction without volume overload, pulmonary embolism, and cor pulmonale must be ruled out. Thus, incorporating measurement of B-type natriuretic peptide into clinical evaluation helps physicians and nurses diagnose heart failure more quickly, especially in patients who have multiple comorbid conditions. Elevated levels of B-type natriuretic peptide indicate a poor prognosis in terms of a higher mortality and more hospital readmissions. Levels of B-type natriuretic peptide could be used to guide therapy and discharge planning for patients admitted with decompensated heart failure.     

血浆B型尿钠肽水平在心力衰竭诊断中的价值

目的探讨慢性心力衰竭（心衰）患者血浆B型钠尿肽（BNP）水平变化及其临床意义。方法采用免疫化学发光分析法,测定63例住院心力衰竭患者血浆B型尿钠肽（BNP）水平（心衰组）和30例健康成人（对照组）血清BNP浓度,并按照纽约心脏病协会（NYHA）分级,比较不同NYHA级别BNP水平差异。结果 （1）心衰组BNP水平（868.5±302.8）pg/mL,明显高于对照组[（101.4±32.8）pg/mL]（P〈0.01）。（2）NYHA分级Ⅱ级患者BNP水平为（629.37±224.56）pg/mL,NYHA分级Ⅲ级患者BNP水平为（853.39±302.43）pg/mL,NYHA分级Ⅳ级患者BNP水平为（1 378.62±433.25）pg/mL,3组间两两比较差异有统计学意义（P〈0.01）。结论 BNP水平随着心衰患者严重程度的加重而增加,对心衰患者的诊断、病情评估、预后判断具有重要临床意义。     

An experimental study of cardiac natriuretic peptides as markers of development of congestive heart failure

The use of cardiac peptide measurements as possible diagnostic tools in congestive heart failure has been extensively discussed in the recent literature. Therefore, the aim of this study was to establish a model of experimental chronic heart failure, and thereby perform a comparative study of secretion and circulating levels of the cardiac peptides atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide (N-terminal proANP) and brain natriuretic peptide (BNP) during evolving heart failure. Chronic heart failure was induced in seven pigs by rapid left atrial pacing for three weeks. The effects of failure induction were documented 24 h after pacemaker deactivation. Hemodynamic indices of cardiac preload, like pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP), were all considerably increased compared to sham operated controls. Likewise, plasma endothelin-L, noradrenaline, renin activity, aldosterone and angiotensin II were all markedly increased. Heart failure was accompanied by significant increases in both estimated cardiac secretory rate and plasma concentrations of all three cardiac peptides, significantly correlated to the PCWP. The directional changes during evolving heart failure were similar, although the percentage increase in plasma BNP was much larger than for ANP and N-terminal proANP. In absolute molar terms, however, the BNP concentration changes were minor compared to those of the other two peptides. The larger percentage increase of BNP might indicate its superiority as a marker of heart failure development, provided a functional assay suitable for clinical use can be designed for a peptide circulating in this low concentration range.     

Increased plasma concentrations of endothelin in congestive heart failure in humans.

Congestive heart failure is characterized by decreased cardiac output and increased peripheral vascular resistance. Endothelin, a peptide found in plasma, is a potent vasoconstrictor. We hypothesized that plasma concentrations of endothelin are increased in humans with congestive heart failure. Plasma samples were obtained from 71 healthy control subjects and 56 patients with congestive heart failure. The mean plasma concentration of endothelin, measured by radioimmunoassay, was 7.1 +/- 0.1 pg/ml in the 71 normal control subjects but 12.6 +/- 0.6 pg/ml in the 56 patients with heart failure (P = 0.001). To evaluate the relationship between circulating endothelin and clinical stage of congestive heart failure, we categorized patients into two groups--those with mild heart failure (New York Heart Association class I or II) and those with severe heart failure (class III or IV). Circulating endothelin in the 24 patients with mild disease was 11.1 +/- 0.7 pg/ml, significantly higher than in normal subjects (P < 0.001). Endothelin in the 32 patients with severe heart failure was 13.8 +/- 0.9 pg/ml, a level significantly higher than that in the group with mild disease (P = 0.029). In the 56 patients with congestive heart failure, a negative correlation was found between plasma concentration of endothelin and left ventricular ejection fraction (r = -0.279; P = 0.037). These data demonstrate that the plasma concentration of endothelin is increased in humans with congestive heart failure and that the level correlates with the severity of disease. Endothelin may have a role in the increased vascular resistance in patients with chronic congestive heart failure.     

慢性心力衰竭患者血清肿瘤相关糖类抗原125和脑钠肽联合测定及其意义

目的探讨慢性心力衰竭（以下简称心衰）患者血清肿瘤相关糖类抗原125（CA125）和脑钠肽（BNP）水平变化及其意义。方法按AHA心衰指南标准随机入选113例慢性心衰患者,按照NYHA心功能分级将其分为两组,A组：NYHA 2级55例,B组：NYHA 3～4级58例。CA125和BNP的测定：采用化学发光技术分别测定所有患者入院第2天CA125和BNP水平。对B组患者出院前复测CA125和BNP水平。结果 NYHA 3～4级组与NYHA 2级组比较,CA125和BNP水平显著升高（〔95±86）U/ml vs（20±26）U/ml（,1052±959）pg/ml vs（317±513）pg/ml,P〈0.01〕,经标准心衰治疗后CA125和BNP水平明显下降（〔95±86）U/ml vs（30±21）U/ml（,1052±959）pg/ml vs（351±213）pg/ml,P〈0.01〕。结论和BNP一样,CA125也是诊断和评价慢性心衰的一个良好指标。     

慢性心力衰竭患者血浆脑钠肽水平研究

目的：研究慢性心力衰竭患者血浆脑钠肽水平与左室功能的关系，探讨血浆脑钠肽在慢性心力衰竭的诊断、病情评估中的临床应用价值。方法：对134例慢性心力衰竭患者（CHF组，NYHA心功能Ⅱ～Ⅳ级）及102例健康体检者（正常对照组），采用ELISA法测定血浆脑钠肽水平，应用心脏彩色多普勒超声诊断仪测定左室射血分数、心脏指数，并将CHF组的血浆脑钠肽水平与左室射血分数、心脏指数作相关性分析。结果：CHF组血浆脑钠肽水平显著高于正常对照组（P〈0．01）。CHF组血浆脑钠肽水平随NYHA心功能分级程度的升高而显著增加（P〈0．01），其与左室射血分数、心脏指数呈负相关（P〈0．05）。CHF组患者经正规治疗后，随着心功能改善，血浆脑钠肽水平明显降低（P〈0．05）；NYHA心功能无改善的患者出院时血浆脑钠肽水平明显高于心功能至少改善一级的患者（P〈0．01）。结论：血浆脑钠肽水平能较好地反映慢性心力衰竭患者左室功能状态，其对于慢性心力衰竭的诊断、病情评估具有临床应用价值。     

The relationship between atrial granularity and circulating atrial natriuretic peptide in hamsters with congestive heart failure

The BIO 14.6 strain of hamster is a model of familial cardiomyopathy complicated by congestive heart failure, sodium retention, and edema. In previous studies, bioassay techniques have demonstrated that the cardiac content of atrial natriuretic peptide (ANP) is reduced in these animals. On the basis of this observation, the syndrome of congestive heart failure has been hypothesized to be due to a deficiency in ANP. The current study was designed to correlate the cardiac content of ANP (determined by immunohistochemical techniques) with plasma circulating ANP (determined by radioimmunoassay). alpha-ANP antibodies were used for both determinations. The content of ANP in the atria was based on the degree of immunoreactive staining present (1 = lowest; 5 = highest), as graded by two observers. The mean granularity score of the cardiomyopathic hamsters was decreased (2.1 +/- 0.3) in comparison with that of age- and sex-matched control animals (3.5 +/- 0.5; P less than 0.05). In contrast, circulating immunoreactive ANP was higher in the hamsters with congestive heart failure than in the control animals--185.5 +/- 27.2 pg/ml versus 77.7 +/- 10.8 pg/ml (P less than 0.005). This study demonstrates that an inverse relationship exists between ANP content in the atria and circulating ANP. Furthermore, this study suggests that these hamsters with congestive heart failure are not deficient in ANP; rather, secretion of ANP is stimulated and storage of the peptide, represented by atrial granularity, is reduced.