Effect of Extracellular Calcium Depletion on Atrial Natriuretic Factor Secretion and Gene Expression: Calcium and ANF release

Extracellular Ca2+ concentration ([Ca2+]o) may be one of the factors affecting atrial natriuretic factor (ANF) release. In the previous studies, there are opposite reports about the effect of [Ca2+]o on ANF secretion. Therefore, the effect of [Ca2+]o depletion on ANF secretion and gene expression was studied in the present research. Isolated right atria from rats were perfused for 6 and 2 hours in the presence and absence of [Ca2+]o, and ANF secretion were measured using radioimmunoassay method. Cyclohexamide was used in another group as a protein synthesis inhibitor. ANF mRNA level in atria measured by Real time PCR. [Ca2+]o depletion induced a significant increase in basal ANF release. This stimulatory effect peaked at 2 h, then started to decrease and reached around basal levels by 6 h. Protein synthesis inhibition by cyclohexamide did not abolish or significantly decrease the stimulatory effect of Ca2+-free media on ANF secretion. The ANF gene expression was not significantly affected by Ca2+-free media. These results suggest that the contractile and endocrine function of atrial cardiocytes are differently affected by [Ca2+]o and may represent an adaptation to the dual roles of the atrial myocytes contraction and secretion

Barberry treatment reduces serum anti-heat shock protein 27 and 60 antibody titres and high-sensitivity C-reactive protein in patients with metabolic syndrome: a double-blind, randomized placebo-controlled trial

Metabolic syndrome is an important risk factor for cardiovascular disease (CVD). The heat shock proteins (HSPs) are associated with risk factors for CVD. The aim of the present study was to survey the effect of barberry on antibody titres to HSPs and high-sensitivity C-reactive protein (hs-CRP) in patients with metabolic syndrome. In our study, subjects (N=106, 79 women and 27 men, 18-65years old) with metabolic syndrome were randomized into two groups: a group of patients who received three capsules of barberry and a control group who received three capsules of placebo for 6weeks. Antibodies against HSPs 27, 60/65 and 70, hs-CRP and lipid profile were determined in patients before (week 0) and after (week 6) intervention. spss software (version 16.0; Inc, Chicago, IL) was used for data analysis. Results showed that barberry had no significant effect on serum level of anti-HSPs 65 and 70. But there was a significant decrease in anti-HSP 27 in both case and control groups (p=0.001 and p<0.001, respectively, in the case and control groups). Barberry decreased significantly anti-HSP 60 in the case group (p=0.03). High-sensitivity CRP was decreased non-significantly (p=0.17) in the case group and increased significantly (p=0.04) in the control group. Barberry decreased significantly low-density lipoprotein and total cholesterol and increased significantly high-density cholesterol (p<0.05). Results of the present study suggested that barberry supplementation in patients with metabolic syndrome decreased significantly anti-HSPs 27 and 60 and hs-CRP levels and improved lipid profile