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.

Background: Atrial natriuretic peptide (ANP) is a 28 amino acid hormone secreted by atrial monocytes in response to local wall stretch. Recent studies have shown that glucocrticoides can express ANP genes and elevate its level. Ketokenazol is an antiadrenal drug used to reduceed glucocorticoides level, thus may result in reduction in ANP level. Thus, the present study was conducted to determine the physiologic effects of ANP on rats receiving ketokenazol.Materials and methods: Human atria were used for ANP. For ANP extraction preparation, tissue was boiled in specific solutions to inactivate intrinsic protease. Then cooling was carried out at 4 degrees centigrade and homogenization and centrifugation were occurred. PH was regulated using dialysis procedure.Results: Pulse, systolic and diastolic pressures were revealed to be higher in ketokenazol group. This may be due to reduction in vascular compliance. Injecting human atrial extract may decrease blood pressure by a slow slope.Conclusion: ANP may be safely used in atherosclerotic patients. Further clinical trials are suggested.

Background and Objective: Clinical studies have indicated, that exercise activity and supplementation may have different effects on heart function and health. The aim of this study was to assess the effects of weight training with whey protein supplementation on ANP, BNP, and Galactin-3 in 60-65 years old sedentary men. Material and Methods: This study was based on a quasi-experimental design. The sample population was selected from volunteers out of the Kahrizak charity sanitarium of the Tehran province. Forthy men were randomly assigned to 4 groups (control, exercise, whey protein, and exercise + whey protein). Whey protein and exercise + whey protein groups were asked to consume whey protein. Training protocol lasted for 6 weeks. Blood levels of ANP, BNP, and Galactin-3, before and after the study were measured. Normality and variance heterogeneity was assessed using Shapiro-Wilk and Levene's tests respectively. The significance of differences between training and supplementation groups was assessed by ANOVA and LSD hock post-test. Results: The results showed that weight training program and in combination with whey protein supplementation significantly reduced Atrial natriuretic peptide (P=0. 001), Brain natriuretic peptide (P=0. 001), and Galactin-3 (P=0. 001), compared to the control group (P<0. 01). Conclusion: The reduction of cardiac injury indices and structural and physiological recovery and the increase of cardiac function have been affected by the synergy of his training and protein.

Background: Acute respiratory distress (ARD) is a critical respiratory failure due to lung injury of neonates leading to the clinical appearance of poor lung compliance. The aimed of the study was to evaluate the diagnostic values in differentiating respiratory from heart diseases with using of N-terminal pro brain natriuretic peptide (NT-pro BNP) and Atrial natriuretic peptide (ANP) in neonates. Material and Methods: Ninety neonates randomly collected from those who hospitalized in the neonate ward of the Ali Ebne abitalib Hospital, Zahedan, Iran. After taking blood samples ANP and NT pro Brian Natriuretic peptide using ELISA kit were measured. The separated serum was kept in-20 ° C until BNP measurement. 250 μ l of the patients’ serum was isolated to assess pro BNP level using ELISA kit (USA). Data were analyzed using SPSS-20 with considering of P< 0. 05. Results: NT pro-BNP level had the highest in cardiac patients and followed by respiratory. The level of NT pro-BNP for control neonates had the lowest. These levels had significant variation (P<0. 05). The level of ANP had the lowest for the cardiac patients. ANP level had the lowest for the acyanotic. NT pro-BNP had the highest concentration in acyanotic patients and and had the second highest concentration in cyanotic. Respiratory diseases ranked in the third levels in concentration of pro-BNP. The level of NT pro-BNP had the lowest for controls. The analysis showed a significant difference in the level of NT pro-BNP (P<0. 05). Conclusion: Many studies revealed that NT pro-BNP cannot be used as a tool for differentiation between cardiac and respiratory as a cause of respiratory distress during neonate, but the results of the present study showed that it would be good biomarker.

Background: The role of physical activity on blood pressure through its effect on Arterial Natriuretic Peptide (ANP) Gene has been previously approved. However, it is not clear what type of physical activity is more effective. The aim of this study was to investigate the effect of 8 weeks resistance training (ladder-climbing) on ANP gene expression in male Wistar rats. Materials and methods: The study was performed on male Wistar rats in control and resistance training groups. The exercise was climbing of a ladder with 85 degrees slope. Exercise intensity was controlled by increasing the weight and closing it to the rat tail. The heart tissue samples were collected and analyzed for ANP gene expression at 72 hours after the last training. Results: The results showed a significant difference between the two groups in ANP gene expression (p<0. 05). The expression was higher in the heart tissue of training group compared to control group. Conclusion: The results of present study suggest that strength training with appropriate pattern and intensity can be a deterrent or control and management of hypertension. Probably the most important factor in resistance exercises is its effect on the structure and function of the heart, including ANP gene expression. Since the role of aerobic training was confirmed in previous studies, it is recommended that these two types of exercises be performed simultaneously.

With interest, I read the article by Khalilian et al. entitled "Relationship between echocardiographic findings and laboratory serum biomarkers in patients with and without low cardiac output" that recently published in your valuable journal. We know that in adult patients, atrial natriuretic peptides (ANP) and brainnatriuretic peptides (BNP) have been used for diagnosis, monitoring of treatment effects, and estimating the prognosis of systolic and diastolic heart failure. Furthermore, ANP would remain quite stable during storage in plasma at -80oC for even 12 months.