Objective: The aim: Study of the patterns of structural changes in the left ventricular myocardial capillaries of rats with arterial hypertension with combined pharmacotherapy with Bisoprolol and Thiotriazolinum.
Patients and methods: Materials and methods: Experiments were conducted on 30 line rats with congenital stress-induced arterial hypertension: 10 animals without treatment and 10 animals with treatment. Pharmacological correction of spontaneous arterial hypertension was performed with 20 mg / kg of Bisoprolol and 50 mg / kg of Thiotriazolinum per os once a day. Pharmacotherapy began at 5 months of age, that is, at a time when compensated heart failure was formed in rats with arterial hypertension. Animals were withdrawn from the experiment 100 days after the start of the correction. Control was provided by intact animals (10 rats) of the corresponding age. While extracted from the experiment rats of all experimental groups had their arterial pressure measured using a plethysmograph, electron microscopic examination of the left ventricular myocardium and morphometric study of volumetric and quantitative densities, cross-section area and form factor of micropinocytotic vesicles were conducted.
Results: Results: In rats with arterial hypertension after application of Bisoprolol and Thiotriazolinum, arterial pressure significantly decreases in experimental rats compared to animals without correction. The number of capillaries in the myocardium after pharmacotherapy increases up to control values, which shows their reparation. In most endothelial cells, organelles retain their integrity and presence that are characteristic of intact rats. The well-expressed processes of transcytosis are shown by the statistical similarity of the quantitative density and the size of the micropinocytotic vesicles in the endothelial cells of the myocardium capillaries of compared experimental animals.
Conclusion: Conclusions: In rats with arterial hypertension, the combination of Bisoprolol and Thiotriazolinum prevents the decrease in the number of capillaries in the myocardium of the left ventricle, promotes the preservation of the ultrastructure of their endothelial cells and maintains the processes of transedothelial transfer of substances at the level of intact animals.
Keywords: electron microscopy; Bisoprolol; blood capillaries; hypertension; myocardium; rat; Thiotriazolinum.