[The effect of the level of total sodium deposited in the myocardium on its stiffness]. / Vliianie urovnia obshchego natriia, deponirovannogo v miokarde, na ego zhestkost'.

AIM: To determine a relationship between the level of total sodium in the myocardium to its stiffness. SUBJECTS AND METHODS: The investigation enrolled 18 hypertensive patients who had suddenly died; their mean age was 40±10 years; mean waist circumference, 102±12.5 cm; height, 170±7.7 cm; myocardial mass, 319±53 g. RESULTS: The variation in the myocardial level of total sodium averaged 211.7±37.5 (min, 71.5; max, 226.17) mmol/l. The sodium level was ascertained to be affected to the greatest extent by myocardial mass (SS=3615.56; p=0.00029) and age at death (SS=1965.568; p=0.0029), whereas gender and smoking had a considerably lower impact (SS=778.584; p=0.03). A univariate regression analysis showed that there was a relationship between myocardial sodium levels and the thickness of the anterior wall of the left ventricle (ß=0.94; p=0.000001; r2=0.88), that of the anterior wall of the right ventricle (ß=0.82; p=0.000021; r2=0.66), and that of the interventricular septum (ß=0.94; p=0.000001; r2=0.89). The wall thickness of the myocardium was established to depend on its sodium level (SS=21813.89; p=0.000001; r2=0.88): the higher sodium amount in the myocardium, the thicker its walls. The average velocity of acoustic wave propagation was 6.24±0.51 m/sec. A significant correlation was observed between sodium concentrations in the myocardium and its stiffness (ß=0.72; p=0.00062; r2=0.49). CONCLUSION: The level of sodium deposited in the myocardium, which is directly related to dietary sodium intake, is significantly correlated with myocardial stiffness. It can be assumed that the elevated level of sodium deposited in the myocardium is an independent factor that changes the stiffness of the myocardium and appears to influence the development of its diastolic dysfunction.

Six- and seven-membered 1-oxa-4-aza-2-silacyclanes as possible correctors of adaptational mechanisms.

The biological activity of eight 1-oxa-4-aza-2-silacyclanes with the OSiCH(2)N fragment including 6-membered 2-sila-5-morpholinones (1-3) and 4-acyl-2-silamorpholines (4-6)and previously unknown 7-membered derivatives of salicylic acid (7, 8) was studied. Compounds 1 and 3-6 show the certain antihypoxic action. Compounds 2 (40 mg/kg), 4 (20 mg/kg), 6 (40 mg/kg), 7 (20 mg/kg) and 8 (40 mg/kg) reduce the physical serviceability of intact animals. Compound 1 (20 mg/kg) influences the physical serviceability in a moderate-positive way on the background of chlorophos-poisoning. Compounds 5-8 displayed protective properties against chlorophos-poisoning at the LD(50) dose and compounds 2, 4, 5, 7 at the LD(100) dose. Influence of compounds 1 and 2 on the emotional-research behavior of mice was studied.