Magnetic Resonance Imaging of Rat Brain in Assessment of the Neuroprotective Properties of Histochrome in Experimental Arterial Hypertension.

The neuroprotective effects of the course therapy with Histochrome in Wistar rats with modeled arterial hypertension were studied by using magnetic resonance imaging (MRI) in diffusion-weighted mode. The behavioral status of the animals was assessed using the open-field test. MRI analysis revealed more pronounced increase in the signaling characteristics of the brain tissue in hypertensive rats in comparison with the control (intact) animals. It was caused by excessive accumulation of fluid in the intra- and extracellular spaces of the brain tissue, which is associated with hypervolemia induced by the multifactorial cardiovasorenal model of hypertension. After a course of Histochrome injections to hypertensive rats, the cerebral microcirculation disorders were leveled, while the behavioral status was characterized by shortened latency of the visit to the center of the open field by 20% and improvement of cognitive activity (by 1.6 times) and the exploratory component (by 30%).

Magnetic Resonance Imaging in Assessment of Cardiac Remodeling in Rats with Experimental Arterial Hypertension.

Magnetic resonance imaging was employed to examine the morphofunctional status of myocardium in Wistar rats with multifactor cardiovasorenal model of arterial hypertension. In 3 months after the onset of experiment, the rats demonstrated a pronounced hypertrophy in left ventricular myocardium mostly due to thickening of the posterior and lateral walls against the background of relatively stable thickness of ventricular septum. The left ventricular endsystolic volume markedly increased in parallel with moderate increase of the end-diastolic volume. The standard calculated indices were used for precise assessment of the type of remodeling of individual myocardial structures. The study showed that multifactor arterial hypertension model was characterized by domination of hypertrophic mode of the left ventricular remodeling, whereas the concentric variant was observed more rarely by 2.5 times. The greatest alterations were observed in the posterior and lateral walls of the left ventricle, which could result from the hemodynamic effects of hypervolemic arterial hypertension.

Assessment of Nephroprotective Potential of Histochrome during Induced Arterial Hypertension.

Magnetic resonance tomography was employed to verify endothelial dysfunction of renal arteries in Wistar and OXYS rats under conditions of induced arterial hypertension. Angiography revealed changes in the size and form of renal arteries of hypertensive animals. In hypertensive rats, histochrome exerted a benevolent therapeutic effect in renal arteries: it decreased BP, diminished thrombus formation in fi ne capillaries and arterioles, demonstrated the anticoagulant properties, partially improved endothelial dysfunction of small renal arteries, and up-regulated the glomerular filtration.