Influence of angiotensin-converting enzyme insertion/deletion polymorphism on nitric oxide production in hypertensives and hypercholesterolaemics

Effects of Interactions among Gene Polymorphisms of the Renin–Angiotensin-Aldosterone System on Hypertension in Turkish People from Southeast Anatolia

Introduction: Hypertension (HT) is characterized by high blood pressure. The reninangiotensin-aldosterone system (RAAS) plays a crucial role in blood pressure (BP) regulation by maintaining vascular tone and the water-sodium balance. We aimed to investigate whether there is any relation between AGT (M235T), ACE (I/D), and AGTR1 (A1166C) genetic polymorphisms and hypertension among Turkish people from Southeast Anatolia.

Method and Results: A total of 210 individuals, consisting of 102 healthy controls and 108 patients with essential hypertension admitted to the Cardiology Department of the Adıyaman University Research and Application Hospital were included the study. DNA isolation was performed from the blood samples via commercial kit. Genotype determination was determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Statistically significant differences were found between the control and patient groups in terms of genotype distribution and allelic frequencies of ACE I/D polymorphisms. Significant differences were found in the frequencies of ICM, DCM, DCT, DAT between the patient and control groups.

Conclusions: In this study, we found a significant association of ACE I/D polymorphism with HT, and we showed that the I allele can increase the risk of HT in Turkish people from Southeast Anatolia. Although we did not find any association between independent AGT M235T and AGT1R A1166C polymorphisms and HT, we observed that the DCM, DCT, and DAT haplotypes of ACE/AGT1R/AGT polymorphisms reduced the risk of hypertension, while the ICM haplotype increased it.

Assessment of the endothelial functions in monocrotaline-induced pulmonary hypertension

Pulmonary hypertension (PH) is a life-threatening disease that causes endothelial dysfunction in the pulmonary vascular bed. Systemic endothelial dysfunction has also been reported in PH. This study compared the systemic and pulmonary vascular responses and some blood biomarkers of endothelial function in monocrotaline (MCT)-induced PH of rats. It also investigated the effect of sildenafil and iloprost treatment. MCT application induced elevation in the right ventricular pressures of the rat heart that had been reversed by sildenafil and iloprost treatment. Acetylcholine-induced endothelium-dependent relaxations of the isolated pulmonary artery were decreased in the PH group and this failure was reversed by sildenafil and iloprost treatment. Acetylcholine-induced endothelium-dependent relaxations of the isolated thoracic aorta were similar in all groups. Serotonin-induced contractions of the pulmonary artery were augmented by PH. In the isolated aorta, serotonin-stimulated contraction was not different in the control and MCT groups, but sildenafil and iloprost treatment decreased serotonin responses. The nitric oxide (NO) level in systemic circulation was not significantly changed by PH. However, sildenafil and iloprost treatments caused a decrease in the plasma level of NO. Asymmetric dimethylarginine levels in plasma were significantly decreased after MCT application and were not recovered by sildenafil and iloprost treatment. Total antioxidant capacity and H2S level of plasma were similar in all groups. Results of this study showed that MCT-induced PH caused specific toxic effects on pulmonary vasculature without any functional effects on the aorta. In addition, it was also demonstrated that sildenafil and iloprost treatments were effective in the MCT-induced PH.