Increase in circulating levels of cardiac natriuretic peptides after hormone replacement therapy in postmenopausal women

The mechanisms that mediate the cardioprotective action of steroid hormones in postmenopausal women are poorly understood. To study the inter-relationship between female steroid hormones and cardiac natriuretic peptides, plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were measured in postmenopausal women, both before and after oestrogen replacement therapy. A total of 22 healthy postmenopausal women (mean age 51.9±4.6 years) were enrolled in the study; all had been postmenopausal for at least 1 year and all reported climacteric symptoms accompanied by increased levels of follicle-stimulating hormone (&gt;30m-i.u./ml) and luteinizing hormone (&gt;20m-i.u./ml), and a reduction in oestradiol (&lt;25pg/ml). All women were given hormone replacement therapy with transdermal oestradiol, either patch (50μg/24 h) or gel (1mg/day), cyclically combined with oral dihydrogesterone (10mg/day for 12 days/month, on days 19-30 of the month). ANP and BNP were measured directly in plasma samples with specific and sensitive immunoradiometric assays before and after hormone replacement therapy (transdermal oestradiol combined with oral dihydrogesterone). Body weight, arterial blood pressure and echocardiographic examination values did not change after hormone replacement therapy. As expected, serum oestradiol increased significantly and gonadotropins decreased as an effect of the hormone replacement therapy. On average, both ANP and BNP had increased significantly after 3 months of hormone replacement therapy [ANP: before treatment, 17.6±9.6pg/ml; after, 23.6±5.6pg/ml (P = 0.0173); BNP: before treatment, 12.6±10.2pg/ml; after, 19.8±14.0pg/ml (P&lt;0.0001)]. Our study indicates that hormone replacement therapy for a period of 3 months induces a rise in the circulating levels of cardiac natriuretic hormones in postmenopausal women. Our data also suggest the working hypothesis that cardiac natriuretic peptides may play an important role in mediating the cardioprotective effects of female steroid sex hormones in women throughout life.</jats:p

Comparison between BNP values measured in capillary blood samples with a POCT method and those measured in plasma venous samples with an automated platform

Letter to the Editor. Our data suggest that it is possible to measure BNP in fresh finger-stick samples of capillary whole blood with an acceptable reproducibility, and within 10 – 20 min to obtain results close correlated to those measured by the automated platform in plasma blood samples collected from a vein. The measurement of BNP in fresh finger-stick samples of capillary whole blood with this POCT method is in particular indicated for the management of HF patients at home and for the BNP assay in neonates and children

Systematic differences between BNP immunoassays: comparison of methods using standard protocols and quality control materials

Background: Recent studies suggested that there are marked systematic differences among BNP immunoassays. In this study we compared the BNP data and clinical results obtained with different immunoassays, including a new method (ST-AIA-PACK, TOSOH Corporation). Methods: BNP was measured on plasma-EDTA samples of healthy subjects (HS, n = 126) and patients with heart failure (HF, n = 31 NYHA I, II; n = 46 NYHA III, IV) using the ST-AIA-PACK and the Triage Biosite (Beckman Coulter) methods. Control samples distributed in the CardioOrmoCheck external quality assessment were also measured with TOSOH and the most used BNP immunoassays in Italy. Results: TOSOH method showed a good correlation (R = 0.976; n = 327) but a mean bias (−46.9%) compared to Triage Biosite. On the base of the results obtained in 10 samples of the CardioOrmoCheck study, TOSOH method showed a strict agreementwith ADVIA Centaur, while it underestimated BNP in comparisonwith Triage (−52.5%) and ARCHITECT methods (−39.4%). The agreement of ST-AIA-PACK and Triage Biosite methods for classification of HF patients was tested using 100 ng/L of BNP; the positive agreement between methods was 65%, overall agreement was 73%. Conclusions: Our results confirm that there are marked differences in measured values among commercial methods for BNP assay