Using a specific radioimmunoassay for atrial natriuretic peptide (ANP), plasma immunoreactive ANP was measured in 17 normal subjects and 83 patients with various diseases. Plasma ANP concentration in normal subjects was 14.1 +/- 1.7 pg/ml (mean +/- S.E.). Relatively high plasma ANP concentrations were detected in patients with diabetes mellitus, hyperthyroidism, atrial fibrillation and liver cirrhosis. Plasma ANP concentrations in the patients correlated positively with mean arterial blood pressure and plasma AVP concentrations. Plasma ANP concentrations in the patients also had positive correlations with left atrial dimension and left ventricular diastolic dimension determined by echocardiography. Another positive correlation was observed in the patients between plasma AVP concentrations and mean arterial blood pressure. These results suggest that ANP is a volume regulatory hormone but also that ANP may be involved in the blood pressure regulating system.

Adolescent↗

PubMedDate not supplied

Atrial natriuretic peptide messenger RNA and peptide in rats with aortic valve insufficiency.

To investigate ANP gene expression in diseased hearts of animals without genetic defects, immunoreactive ANP (IR-ANP) and ANP mRNA were measured in a rat with aortic valve insufficiency (AI), which was produced by puncturing one of the aortic valve leaflets with a plastic rod. Plasma IR-ANP concentration was higher in AI rats than in sham rats (p less than 0.05). Decreased atrial concentration of IR-ANP (p less than 0.05) and unchanged atrial ANP mRNA concentration were shown in AI rats. The ventricular concentrations of IR-ANP and ANP mRNA in AI rats were 5.4 and 2.4 times higher than those in sham rats (p less than 0.05, respectively). These results demonstrate that gene expression of ventricular ANP is markedly increased in AI rats while that of atrial ANP is not changed.

Animals↗

PubMedDate not supplied

Diurnal variation in serum remnant-like lipoproteins, platelet aggregation and fibrinolysis in healthy volunteers.

Postprandial triglyceridemia and 'remnantemia' may better reflect the atherosclerotic risk than triglyceride (TG) levels in the fasting state. Recently, a new method was developed based on a monoclonal antibody recognizing an epitope distal to the carboxyl end of apo B48 which allows easy measurement of remnant-like lipoproteins (RLP). This study was performed in order to investigate RLP response to a standardized fat meal and establish a normal diurnal pattern of RLP in blood and compare it to platelet aggregation and fibrinolysis in healthy young men. We investigated 7 male volunteers (age range 18-23 years) who received a standardized fat meal (Othsuka Pharmaceutical Company, Japan) containing 32.9% lipids, 2.5% protein, 2.5% carbohydrate, 0.3% calcium and 0.1% phospholipids, and 74 mg/100 g cholesterol (C) at 7:30. The energetic value of this cocktail was 341 kcal/100 g. Area under curve (AUC) responses in TG, RLP-TG and RLP-C after the meal were as follows: for TG 28.66 +/- 8.94; for RLP-TG 17.54 +/- 5.55; for RLP-C 1.27 +/- 0.42 mg x dl-1 x h-1. These responses were correlated to each other. Surprisingly, collagen-induced platelet aggregation in whole blood was negatively related to RLP-C AUC. Fluctuation patterns of TG, RLP-TG and RLP-C concentrations during the day were remarkably similar, peaking in this particular group of subjects at 10:00-12:00 and at about 23:00, whereas cholesterol was decreasing late in the night and very early in the morning. This pattern was different from those of platelet aggregation and fibrinolysis parameters.

Adolescent↗