In the pathogenesis of arterial hypertension (AH), the renin-angiotensin-aldosterone system plays a key role in helping to maintain elevated blood pressure. At the same time, the state of angiotensin-II production (AT II) and the expression level of its receptors on target cells determine the formation of most of the effects underlying the pathogenesis of associated clinical conditions in such patients. Thus, the study of the pathogenesis of AH, namely the study of the role of the AT II axis, the AT II receptor, is an actual scientific and practical task.
Aim. Given the important role of type 1 receptors for AT II in the formation of pathological changes in arterial hypertension, the purpose of this study was to study the peculiarities of the effect of their expression on biochemical processes in patients with arterial hypertension.
Material and methods. In the course of the clinical study, 60 patients of both sexes with hypertension aged 45 to 55 years old were admitted to the clinic for planned treatment. Depending on the initial level of expression of receptors for AT II (AT1R), determined by the serum concentration of the soluble form of type 1 receptors for AT II, the patients were divided into two subgroups with conditionally low (corresponding to the concentration of the soluble form of the receptor for AT II 0.66 ng/ml) and conditionally high (1.57 ng/ml) expression. The analysis showed that high expression of AT1R is associated with elevated plasma levels of renin by 30.8% (p=0.0005), AT II by 48.1% (p=0.00001), E-selectin by 47.9% (p=0.0001), VCAM-1 by 29.1% (p=0.00001), ICAM-1 by 52.9% (p=0.00001), VE-cadherin by 50.9% (p=0.00001), endothelin-1 by 48.8% (p=0.0005), an ACE inhibitor by 13.6% (p=0.047), and CRP by 74.1% (p=0.00002 ) and endoperoxide by 29.7% (p=0.009). Against this background, there was a decrease in the level of apoA1 by 21.6% (p=0.027), ACE by 20.1% (p=0.1), the level of antioxidants by 22.3% (p=0.00001). The analysis showed that in the group with initially high expression of AT1R, there was an increased blood pressure, the level of which, on average, exceeded the values of patients with low expression of the indicated receptor by 24.5 mm Hg (p=0.011). Against the background of therapy in the group with high expression of AT1R, plasma renin activity decreased by 20.3% (p=0.013), endoperoxide by 8.4% (p=0.038), an ACE inhibitor by 14.6% (p=0.02). At the same time, the level of apoA1 increased by 8.5% (p=0.036), antioxidants by 8.6% (p=0.036), ICAM-1 by 5.3% (p=0.05), VE-cadherin by 2.5% (p=0.07). The level of the remaining factors was not statistically significant. In the subgroup with low expression of the AT II receptor, during treatment, there was a decrease in endoperoxide by 12.8% (p=0.031), an ACE inhibitor by 5.5% (p=0.044) without significant changes in other indicators.
Conclusion. In hypertensive patients, higher expression of AT1R is associated with high activation of immune-inflammatory mechanisms, dyslipidemia, an imbalance of the lipid peroxidation system and antioxidant protection, as well as higher renin-angiotensin-aldosterone system activity and increased arterial pressure. On the background of antihypertensive therapy, partial compensation of the identified changes is achieved, including a moderate increase in the level of antioxidants, a decrease in the concentration of endoperoxide, renin activity and an increase in the level of apoA1, while maintaining an increased level of AT II, high expression of receptors to it. These changes indicate the need for further search for effective antihypertensive therapy strategies aimed at limiting the activity of renin-angiotensin-aldosterone system in patients with hypertension.
Role of the Renin-Angiotensin-Aldosterone System in Various Disease Processes: An Overview
