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Biomedical subjects

G A Drozdova

Publications and source records attributed to G A Drozdova.

At least 19 recordsLinked to original sources
PubMed2005

Changes in myocardial blood supply during experimental hypertension treated with verapamil in rabbits.

Rabbit hearts were studied at different periods of experimental arterial hypertension and its treatment with verapamil. Morphological study revealed a progressive decrease in the number of capillaries per unit mass during the development of myocardial hypertrophy in hypertensive hearts. In hypertensive animals treated with verapamil the density of capillaries in both ventricles did not decrease, but verapamil injected to intact animals sharply decreased this parameter.

Animals↗
PubMed2004

Initial mechanisms of the development of hypertonic heart.

In rabbits, arterial hypertension was simulated according to Goldblatt. One, 2, 4, and 6 weeks after surgery, the hearts of control and experimental animals were extirpated for morphological examination. In semithin sections of the left and right ventricles, morphometry was performed using an Avtandilov grid. Ultrathin sections of these organs were examined under an electron microscope. It was found that the initial signs of myocardial hypertrophy appeared soon after hypertension modeling, and more early in the right ventricle. Activation of apoptosis was noted in cardiomyocytes of both ventricles, and its intensity correlated with the degree of myocardial hypertrophy. It is hypothesized that apoptosis limits the development of hypertrophy in the myocardium.

Animals↗
PubMed2001

Possible mechanism of regression of myocardial hypertrophy.

Structure of the myocardium was studied in rabbits with renovascular hypertension during the development of myocardial hypertrophy and its regression under the effect of beta-adrenoceptor antagonist lopressor. Myocardial hypertrophy was associated with ultrastructural changes in cardiomyocytes, while lopressor therapy led to their regression and normalization of cardiomyocyte ultrastructure. Regression of hypertrophic changes was accompanied by a marked increase in the number of extracellular nuclei, which indicated enhanced apoptosis of cardiomyocytes.

Adrenergic beta-Antagonists↗
PubMed1998

[Weak-flow membrane blood oxygenation in treatment of patients with peritonitis].

The application of the level of molecules with medium molecular mass (MM) and wave length E254 and 280 nm was tried in 30 patients, operated on for various diseases of the organs of abdominal cavity and their purulent complications. Besides routine treatment weak flow membrane blood oxygenation was carried out. As a result of the study it was established that the level of medium molecular peptides appears to be a criteria of effectiveness of the weak-flow membrane blood oxygenation and determines duration of the procedure. The initial concentration of MM from 1,0 relative units and more duration of the blood oxygenation period should be limited by 2 hours. This method can be regarded, as independent mode od detoxication.

Adult↗
PubMed1993

[The interventricular functional-morphological correlations in chronic overloading of the primarily intact left heart in a model of experimental vasorenal hypertension].

This investigation shows the work of the heart as an integral functional system where each of the ventricles plays its own vital role, especially in the case where only one ventricle is pathologically affected. Moreover, the changes in the right heart have been carefully studied, thus showing its immediate involvement in cases of left heart hemodynamical overloading. The experiment was carried out on 178 mature rabbits with a model of vasorenal arterial hypertension based upon coarctation of the abdominal aorta just above the renal arteries. Arterial and intraventricular parameters of blood pressure were registered and morphological investigation involved transmission electron microscopy of the left and right ventricular myocardia, especially paying attention to mitochondrial changes in the cardiomyocytes. The right ventricle reacts at the same time as the left ventricle, although it shows a more intensive function and reaches decompensation earlier than the left heart.

Animals↗
PubMed1993

[An assessment of the differences in the reaction of the left and right heart ventricles to a long-term rise in systemic arterial pressure in experimental renoprival arterial hypertension in rabbits].

Different parameters of the function of the left and right heart ventricles were investigated in rabbits with renoprival arterial hypertension during a period of 52 weeks from the moment of modelling the process. As a result, this process was divided into 3 stages: 1. The establishment of compensation (1-4 weeks); 2. Compensation (6-10 weeks); 3. Decompensation (22-52 weeks). In mathematical prognosis of the time-course changes in the parameters associated with different stages of the process, the prognostic data were shown to be close to the experimental ones during prognosis for the left ventricle in the second stage, and for the right ventricle in the first stage. While prognosing for the left ventricle in the first stage and for the right ventricle in the second stage, the data obtained were significantly different from the experimental ones. These results suggest a conclusion that the right ventricle adapts itself to cardiac overload quicker than the left ventricle, but it also gets "worn out" quicker than the latter due to the conditions of "rigid" functioning in the second stage of the process when the adaptive potentials of the heart are limited.

Animals↗
PubMed1989

[Effects of atrial natriuretic factor on the cardiovascular system and several parameters of renal excretory function in spontaneously hypertensive rats].

The influence of atrial natriuretic factor on several parameters of cardiovascular system and renal excretory function in spontaneously hypertensive rats has been investigated. The exogenously administered atrial natriuretic factor, not influencing the arterial pressure level and electrolyte concentration in the urine, at the same time breaks the links between APmax and the intensity of electrolyte excretion in urine.

Animals↗
PubMed1986

[Diagnostic significance of indices of kininogenesis in infectious-allergic myocarditis].

Three patterns of kininogenetic changes: enhanced (50% of patients), depressed (40%) and qualitatively-different (10%) kininogenesis, were identified through 3 measurements of blood kallikrein-kinin (BKK) activity by kininogenase techniques in patients with infectious allergic myocarditis and myocarditic cardiosclerosis. The intensity of individual phases of kininogenesis is conditioned by the activity of total plasma kallikrein, its conformation and the level of kallikrein inhibitors. During the activated kininogenesis phase, a direct relation can be seen between changes in the activity of the above-mentioned parameters and clinical severity of the disease. The measurement of total kallikrein activity, kaolin adsorption of this enzyme, and kallikrein inhibitors may be useful as an additional diagnostic test. The pattern of changes in BKK activity parameters may be indicative of persisting or progressing myocardial inflammatory allergic process in patients with myocarditic cardiosclerosis. The treatment for myocarditis with conventional anti-inflammatory agents, leaving out the drugs controlling kininogenetic changes, fails to produce complete recovery and the normalization of BKK activity.

Adult↗
PubMed1986

[Structural changes in the lungs induced by different levels of hyperbaric oxygenation].

Morphological and ultrastructural changes in the lungs of 30 rabbits placed into the altitude chamber with 100% O2 and the pressure of 2, 2.5, 3 and 4 ata for 60 min daily during 1, 2 and 3 weeks have been studied. Morphological changes in the lungs were shown to depend on the degree and duration of oxygen pressure. 2 ata for 60 min daily during two weeks or 2.5 ata for 60 min daily during one week were considered to be safe regimens of hyperbaric oxygenation. Microcirculatory disorders and dystrophic changes of the aero-hematogenic barrier (AHB), its increased permeability, the development of intraalveolar and interstitial edema are observed in the lungs at a higher pressure of 3 or 4 ata. The endothelium and type I alveolocytes are more sensible to high doses of hyperbaric oxygenation. Hydropic degeneration and exfoliation of cells from the basilar membrane are gradually increasing. Type II alveolocytes are more stable to the destructive action of hyperbaric oxygenation. Greater dystrophic changes in other AHB elements are associated with the hypertrophy of mitochondria and lamellar bodies. The described AHB changes are more expressed in atelectasis areas.

Animals↗