Japanese scientists have discovered how salt triggers the development of hypertension. About it reported in a press release on EurekAlert!.
Hypertension is one of the major risk factors of cardiovascular diseases worldwide and the death from stroke and heart attack. Approximately 40 percent of the adult population aged 25 years and older suffer from high blood pressure.
The development of hypertension contributes to the use of table salt (NaCl). The more the human body comes chloride of sodium, the more sodium ions accumulate in plasma and cerebrospinal fluid (CSF). This, in turn, leads to the excitation of the sympathetic nervous system regulating the circulation.
It is shown that a specific sodium channels, that is, protein structures in the cell membrane through which the cell receives the sodium ions are formed in certain glial cells, including astrocytes and cells of the ependyma — the membrane lining certain structures of the Central nervous system. Such structures are circumventricular the bodies that provide the link between the nervous and circulatory systems. Scientists have found that these sodium channels are the brain “sensors” that monitor the increase in the concentration of sodium ions in the blood and in the cerebrospinal fluid.
The researchers demonstrated that in mutant mice, in which circumventricular authorities lack sodium channels, activation of sympathetic nerves occurred with a high level of salt intake. In mice as wild type glial cells has been a series of biochemical reactions. The sodium ions in the extracellular environment provoked the opening of sodium channels and influx of Na into the cytoplasm caused an intense formation of lactate. Lactate and hydrogen ions were released from the cells and activated neurons in the hypothalamus and in the medulla that stimulates the sympathetic nerves.