Medullary vasomotor center: a modern view of the structure, function and its role in arterial hypertension pathogenesis

The medullary centers of blood pressure regulation have been in the field of vision of both physiologists and doctors for a very long period of time. This is mainly due to the abundance of structures and interstructural interactions in the brain stem, involved in maintaining blood pressure. Advances in research technology open new opportunities these days to look at this problem from a different angle. Moreover, research of medullary centers of blood pressure regulation will make it possible to understand better the mechanisms of persistent increase in blood pressure, which will create the preconditions for the formation of new pathogenetically substantiated therapeutic approaches in the treatment of such a widespread and dangerous pathology as arterial hypertension. Therefore, the aim of this work was to analyze modern views about the structure and composition of the medullary vasomotor center, its functions and its role in the arterial hypertension development. To achieve this goal, the search by keywords: arterial hypertension, baroreflex, NTS, DMN, RVLM, CVLM, CPA, SHR, LC and analysis of scientific articles from the databases of search engines Google Scholar, Web of Science, Pub Med was done. Conclusions: 1. The analysis of literature sources showed that the concept of "medullar vasomotor center" includes a number of brainstem formations, the most studied of which are the structures of the dorsal complex of the vagus nerve (the nucleus of the solitary tract, the dorsal motor nucleus, area postrema), the rostral and caudal ventrolateral regions of medulla, caudal pressor area, noradrenergic structures of the brainstem, in particular the locus coeruleus, as the biggest of them. 2. According to literary sources, arterial hypertension is accompanied by the changes in the morphofunctional state of the above-mentioned structures. The most common mechanisms are violation of the neurotransmitter composition within the structure and the neuroinflammatory process.

Vasomotor Center? A Possible Role in the Treatment of Hypertension

The global burden of hypertension and associated co-morbidities (cardiac failure, renal failure), is constantly rising despite the availability of newer drugs. Therefore, this study was planned to review the role of VMC (Vasomotor Center) in hypertension along with adding stress-relieving methods in lifestyle measures to prevent an epidemic of hypertension. For this purpose textbook of physiology, and various reference studies were used. The text-book of physiology suggests the location of VMC (Lower pons and medulla) and its functioning related to blood pressure regulation. It receives a signal from baroreceptors and produces either a decrease or an increase in blood pressure. The VMC is influenced by the cerebral cortex and hypothalamus. The pathophysiology suggests that possibly chronic stress, mental overwork disturbs the cortical influences to hypothalamus and shifts VMC to a higher level and that results in high basal sympathetic discharge and increased LV ejection force along with shifting of baroreceptors and renal mechanism to a new higher level which brings the blood pressure or whole body vasculature to the same high level resulting in hypertension. The repetition of the same process shifts BP even higher. The centrally acting drugs, mental rest, sound sleep and stress relieving methods like yoga, Vipassana, etc. may help to reduce cortical impulses and to bring VMC back to normal. VMC will automatically correct various BP control mechanisms and bring back BP to normal. Thus continuous efforts are needed to remove precipitating factors of hypertension. The methods to relieve stress and exhaustion must be employed in lifestyle for hypertension besides JNC guidelines.

L.L. Fofanof: 140th anniversary of his birth. Contribution to science

The article is dedicated to Professor L.L. Fofanof’s scientific activity. He headed the faculty therapeutic clinic of Kazan Imperial University in 1915-1920. Being a student L.L. Fofanov was interested in pathological anatomy and physiology. His dissertation «To physiology of n. depressoris» was dedicated to studying the vasomotor center. During his visit in Germany he worked a lot. In Charite together with Professor His he studied gout and its treatment with Radium emanation. In Halle clinic under Professor Schmidt’s supervision he studied assimilation of starch in normal and pathological digestion. L.L. Fofanov also made a contribution to tuberculosis treatment: with professor V.F. Orlovskiy he studied treatment of tuberculosis with simulated pneumothorax. In his research professor L.L. Fofanov paid great attention to the issues of pathogenesis and pathogenetic substantiation of the clinical manifestation and treatment. During the World War I and Civil War he fought against typhus epidemies: he saw patients, gave lectures, studied the features of myocardial involvement. He died in 1920 from typhus.

Continuous hypertension and tachycardia after resection of a hemangioblastoma behind the dorsal medulla oblongata: relationship to sympathetic overactivity at the neurogenic vasomotor center

A very rare case of continuous hypertension and tachycardia after excision of a cerebellar hemangioblastoma at the dorsal medulla oblongata is presented. This 21-year-old man was admitted to the authors' hospital with a headache and dizziness. Radiological examination revealed a tumor located behind the dorsal medulla oblongata and compressing it substantially. The tumor was completely resected, but after the surgery the patient experienced prolonged hypertension and tachycardia. Postoperative MR imaging showed a small injury at the dorsocaudal medulla that was located at the caudal site of the nucleus of the tractus solitarius (NTS). Because the NTS has been reported to play a central role in cardiovascular regulation along with the rostral ventrolateral medulla, the authors considered it possible that the NTS injury was the cause of the prolonged elevation of sympathetic tone.