Abstract
The aim of our study was to determine the characteristics of the BNP and AT II expression in the LC structure of rat brain stem with experimental (genetically determined essential and secondary endocrine-salt) arterial hypertension and to give a comparative description of the expression pattern of these peptides in etiologically different types of arterial hypertension.Materials and methods. The study was carried out on adult 30 male rats. 20 Wistar animals were divided into two groups – control (10 rats) and 10 rats with simulated endocrine-salt AH (ESAH) and 10 rats of the SHR line with essential AH (EAH). The expression parameters of neuropeptides, such as the content, concentration, and relative area of the immunoreactive material, were studied using an immunohistochemical method.Results. It was found that from all BNP expression parameters in the locus coeruleus structure, only relative area increased significantly in both groups. The concentration did not significantly change, and the content of immunoreactive material increased significantly only in animals with ESAH. At the same time, all parameters of angiotensin II expression increased significantly in both experimental groups. Thus, in rats with experimental arterial hypertension in the locus coeruleus structure, more pronounced changes in expression parameters are characteristic for angiotensin II, rather than for BNP. There is a discrepancy between levels of pressor angiotensin II expression and depressor BNP expression in the direction of angiotensin II expression increasing during the arterial hypertension formation. The nature and peculiarities of these neuropeptides expression in the LC structure depend on the key link of the pathogenesis of the modeled arterial hypertension.Conclusions. In rats of the control group with normal blood pressure in LC structure, AT II is more represented. The content and concentration of IRM to AT II are 2.32 and 2.19 times higher than the corresponding BNP values. Prevalence of AT II in the LC structure of the brainstem remains even when arterial hypertension is formed, regardless of its etiology. However, the etiopathogenetic mechanisms of arterial hypertension development impose their own characteristics. In EAH, the content and concentration of AT II is higher than BNP by 4.58 and 3.59 times; in ESAH – by 2.16 and 2.83 times. In the pathogenesis of essential arterial hypertension formation an important role is played by a change in the central control of blood pressure regulation. It is characterized by a significant predominance of the pressor component AT II over the depressor BNP in the brainstem LC structure.
Highlights
It is well known that the level of blood pressure (BP) is directly related to such indicators as cardiac output (CO) and total peripheral vascular resistance (TPVR) [1]
In essential human hypertension (EAH) group, it was higher by 6.51 % and in animals with endocrine-saline hypertension (ESAH) – by 6.94 %, in comparison with the control animals
As for the immunoreactive material (IRM) content to Brain natriuretic peptide (BNP) in the locus coeruleus (LC) structure, it significantly increased by 23.17 % only in the ESAH group, which led to a significant difference of this parameter between the groups of rats with ESAH and EAH becoming 28.21 % higher (Table. 1)
Summary
It is well known that the level of blood pressure (BP) is directly related to such indicators as cardiac output (CO) and total peripheral vascular resistance (TPVR) [1]. Today, when the effects and mechanisms of blood pressure regulation by hormonal and humoral agents are well studied, the neurogenic blood pressure control is still a significant issue and arouse the interest of a large number of researchers. In this regard, the problem of studying the functional state of the ANS regulatory structures in conditions of high blood pressure, especially its sympathetic regulation link, becomes actual. Despite the fact that the effects, localization and prevalence of these two peptides in the central nervous system are being actively studied today, the features of these neurohormones balance, the dependence of the BNP and AT II expression level from the type of experimental pathology are practically absent.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
