scholarly journals Mechanism of Electrocardiographic T-Wave Flattening in Diabetes Mellitus: Experimental and Simulation Study

2017 ◽  
pp. 781-789 ◽  
Author(s):  
K. A. SEDOVA ◽  
J. E. AZAROV ◽  
N. V. ARTEYEVA ◽  
A. O. OVECHKIN ◽  
M. A. VAYKSHNORAYTE ◽  
...  

In the present study we investigated the contribution of ventricular repolarization time (RT) dispersion (the maximal difference in RT) and RT gradients (the differences in RT in apicobasal, anteroposterior and interventricular directions) to T-wave flattening in a setting of experimental diabetes mellitus. In 9 healthy and 11 diabetic (alloxan model) open-chest rabbits, we measured RT in ventricular epicardial electrograms. To specify the contributions of apicobasal, interventricular and anteroposterior RT gradients and RT dispersion to the body surface potentials we determined T-wave voltage differences between modified upper- and lower-chest precordial leads (T-wave amplitude dispersions, TWAD). Expression of RT gradients and RT dispersion in the correspondent TWAD parameters was studied by computer simulations. Diabetic rabbits demonstrated flattened T-waves in precordial leads associated with increased anteroposterior and decreased apicobasal RT gradients (P<0.05) due to RT prolongation at the apex. For diabetics, simulations predicted the preserved T-vector length and altered sagittal and longitudinal TWAD proven by experimental measurements. T-wave flattening in the diabetic rabbits was not due to changes in RT dispersion, but reflected the redistributed ventricular repolarization pattern with prolonged apical repolarization resulting in increased anteroposterior and decreased apicobasal RT gradients.

2019 ◽  
Vol 11 (2) ◽  
pp. 191-195
Author(s):  
Patrick E. ABA ◽  
Miracle N. EDEH

Selection of appropriate ages of rats for experimental diabetes mellitus studies has been posing great challenges to researchers as the rats may either not come down with diabetes or may even die upon induction. This study investigated the influence of age as a possible factor affecting successful induction of diabetes mellitus in albino Wistar rats. One hundred male albino Wistar rats of varying ages weighing between 23.63 ± 0.46 g and 279.00 ± 27.00 g and assigned into ten (10) groups of ten rats per group were used for the study. Diabetes was induced in groups 1-9 consisting of rats aged 3, 5, 7, 9, 11, 13, 15, 17 and 19 weeks respectively by injecting 160 mg/kg of alloxan monohydrate intraperitoneally while group 10 rats (aged 12 weeks) served as normal control. Fasting blood glucose levels and the weights of the rats were determined on 0 h, 24 h, 48 h, 72 h and 96 h post alloxan monohydrate injection. Body conditions and behaviors of the rats were subjectively scored. Results showed that rats in groups 3-9 came down with hyperglycemia 48 h post-alloxan injection. The body conditions and behaviors of groups 3 (aged 7 weeks) and 4 (Aged 9 weeks) rats compared very well (p<0.05) with those of the normal control rats. It was concluded that rats aged 7-9 weeks were most suitable for use in studies involving induction of experimental diabetes mellitus using alloxan monohydrate at the dose of 160 mg/kg intraperitoneally.


Author(s):  
Р.И. Айзман ◽  
А.П. Козлова ◽  
Е.И. Гордеева ◽  
М.С. Головин ◽  
Г.А. Корощенко ◽  
...  

Цель - исследование влияния куркумы длинной и галеги восточной на осмо- и ионорегулирующую функции почек крыс при аллоксан-индуцированном сахарном диабете и острой почечной недостаточности в эксперименте. Методика. Эксперименты выполнены на самцах крыс Wistar (n=70) с моделью сахарного диабета (1-я серия) и острой почечной недостаточности (2-я серия). В обеих сериях животные были поделены на 3 группы: крыс 1-й группы содержали на стандартном корме, крысам остальных групп в корм добавляли куркуму (2-я группа) или галегу (3-я группа) (2% от массы корма). На 7-е сут эксперимента проводили исследование диуретической и ионоуретической функций почек натощак и после 5% водной нагрузки. Концентрацию ионов в моче и плазме определяли методом пламенной фотометрии; осмотическую концентрацию биологических жидкостей - методом криоскопии; биохимические показатели крови - колориметрическим методом. Результаты. У животных с сахарным диабетом фоновый диурез, а также экскреция натрия и калия были статистически значимо выше, чем у контрольных животных. При острой почечной недостаточности наблюдался более низкий уровень диуреза и ионоуреза, особенно после водной нагрузки. Прием куркумы и галеги вызывал улучшение осмо- и ионорегулирующей функции почек у крыс с сахарным диабетом, и практически не влиял на эти функции почек при острой почечной недостаточности. Заключение. При сахарном диабете оба фитопрепарата вызывали понижение концентрации глюкозы, креатинина, мочевины и улучшение ионно-осмотических показателей плазмы крови, при этом эффект куркумы был выражен отчетливее. При острой почечной недостаточности эти фитопрепараты не давали описанного эффекта. Aim. To study effects of the phytomedicines, Curcuma longa and Galega orientalis, on osmosis- and ion-regulating renal functions in rats with experimental diabetes mellitus (DM) and acute renal failure (ARF). Methods. Experiments were performed in two series on Wistar male rats (n=70) with modeled diabetes mellitus (series 1) and acute renal failure (series 2). In each series, the animals were divided into 3 groups, 1) rats of group 1 receiving a standard diet; 2) rats of groups 2 and 3 receiving a standard diet supplemented with turmeric or galega (2% of food weight), respectively. On the 7th day of the experiment, the diuretic and ionuretic renal function was studied in fasting state and after 5% water loading. Concentrations of ions in urine and plasma were determined by flame photometry; osmotic concentrations of biological fluids were measured by cryoscopy; blood biochemical parameters were measured by colorimetry. Results. In diabetic rats, background diuresis and sodium and potassium excretion were significantly higher than in the control animals. In rats with acute renal failure, diuresis and ionuresis were significantly lower, particularly after the water loading. Turmeric and galega supplementation improved the osmotic and ion-regulating renal function in diabetic rats and left practically unchanged these functions in rats with acute renal failure. Conclusion. In rats with diabetes mellitus, both herbal remedies reduced concentrations of glucose, creatinine, and urea and improved ion-osmotic parameters of blood plasma with a more pronounced effect of turmeric. In acute renal failure, these phytomedicines did not produce the described effects.


2018 ◽  
Vol 14 (65) ◽  
pp. 152
Author(s):  
O. Ya. Zhurakivska ◽  
Yu. V. Bodnarchuk ◽  
V. M. Pertsovych ◽  
H. B. Kulynych ◽  
V. A. Мiesoiedova

Sign in / Sign up

Export Citation Format

Share Document