Impaired response of atrial natriuretic peptide to acute water load in obesity and in anorexia nervosa

Abstract

Plasma atrial natriuretic peptide (ANP) concentrations were determined in basal conditions and after infusion of 1000 ml of 0.9% NaCl in women with anorexia nervosa, in normotensive obese women and in healthy women of the control group. Additionally, in the obese women and in the controls, plasma ANP was measured after iv injection of clonidine. Anorectic patients were investigated in the period of weight loss (mean deficit of body weight was 40%). The mean body mass index (BMI) in the obese women was 36.44 +/- 0.36 kg/m2. Basal plasma ANP concentrations were significantly higher in both anorectic and obese women (p < 0.001 and p < 0.01, respectively). The response of ANP to acute water load was markedly blunted in anorexia nervosa and in obesity (delta % = 232% in control group, 14% in anorexia nervosa and 21% in obesity. A significant increase of ANP was found after iv injection of clonidine in the control group and in obesity (p < 0.001 and p < 0.01, respectively). However, the increase of response (expressed as a percentage change) in obese patients was lower than that in the control group (delta % = 64% and 199%, respectively). The response of ANP to alpha 2-adrenergic stimulation was higher than to hemodynamic stimulus. Our results suggest that the disturbed control of neuropeptides and neurotransmitters as well as changes in peripheral metabolism may explain the impaired responsibility of ANP to hemodynamic stimuli in anorectic and obese patients.

Defective Regulation and Action of Atrial Natriuretic Peptide in Type 2 Diabetes

“…Raised plasma ANP levels, urinary volume and sodium excretion have been reported in subjects over the age of 65 years in contrast to middle-aged and young subjects [31 -33]. Obese individuals have also been found to have higher circulating ANP levels than lean subjects [34,35]. Our diabetic patients were middle-aged and not one was obese.…”

Hormonal replacement therapy affects calcitonin gene-related peptide and atrial natriuretic peptide secretion in postmenopausal women

“…CGRP-containing vasodilator nerves of rat mesenteric vessels are inhibited by norepinephrine, through the activation of a 2 -adrenoceptors (32). On the other hand, infusion of clonidine in conscious rats (33) and humans (14) produces a marked increase in plasma ANP levels. The apparent contrast between these data and our results on the effects of clonidine on ANP levels is possibly due to the different means of administration of the drug: acute infusion compared with long-term oral clonidine.…”

“…Saline infusion has been shown to increase circulating ANP levels in healthy subjects (13). Infusion of clonidine, an a 2 -adrenergic agonist, has also been shown to produce a marked increase in plasma ANP levels in healthy subjects (14).…”

Epigenetic Downregulation of Atrial Natriuretic Peptide but not Vasopressin mRNA Expression in Females with Eating Disorders is Related to Impulsivity

“…Dysregulation of ANP plasma levels have been implicated in the pathophysiology of depression and protracted alcohol withdrawal (Kiefer et al, 2002;Strohle and Holsboer, 2003). Elevated plasma levels of ANP have been reported in women suffering from AN (Ohashi et al, 1988) as well as an impaired response of ANP to an acute water load (Baranowska et al, 1995). To our knowledge, no results have been published regarding patients suffering from BN.…”