Tibor Stracina

Masaryk University | MUNI · Department of Physiology

Purpose The aim of this study is to design a method of myocardial T1 quantification in small laboratory animals and to investigate the effects of spatiotemporal regularization and the needed acquisition duration. Methods We propose a compressed‐sensing approach to T1 quantification based on self‐gated inversion‐recovery radial two/three‐dimensiona...

Contemporary society is characterized by rapid changes. Various epidemiological, political and economic crises represent a burden to mental health of nowadays population, which may at least partially explain the increasing incidence of mental disorders, including schizophrenia. Schizophrenia is associated with premature mortality by at least 13–15...

Based on the World Health Organization statistics, cardiovascular diseases represent the major cause of death worldwide. Although a wide range of treatment approaches and pharmaceuticals is available, the therapy is often not effective enough and therefore health risks for the patient persist. Thus, it is still essential to test new drug candidates...

Gastropathy is one of the most common diseases of the human gastrointestinal tract. Apart from its consequences in the stomach, it is also manifested in other parts of the digestive tract, particularly in the duodenum. The aim of this pilot study was to verify on animal model the empirically observed alleviation of gastropathy symptoms in patients...

Polyunsaturated fatty acids (PUFA) play an important role in reparative processes. The ratio of PUFAs n-3 to n-6 may affect wound healing. The study aimed to evaluate the effect of dietary supplementation with n-3 and n-6 PUFA in two proportions on skin wounds in laboratory rats. Adult male Wistar rats received 20% fat emulsion with a ratio of 1.4:...

Cardiovascular system and its functions under both physiological and pathophysiological conditions have been studied for centuries. One of the most important steps in the cardiovascular research was the possibility to record cardiac electrical activity. Since then, numerous modifications and improvements have been introduced; however, an electrocar...

Aims Although voltage-sensitive dye di-4-ANEPPS is a common tool for mapping cardiac electrical activity, reported effects on electrophysiological parameters are rather. The main goals of the study were to reveal effects of the dye on rabbit isolated heart and to verify, whether rabbit isolated heart stained with di-4-ANEPPS is a suitable tool for...

Prolonged QT interval is an independent risk factor for development of ventricular arrhythmias. Haloperidol is one of the drugs inducing QT prolongation. Previous studies showed that haloperidol affects not only QT duration but also heart rate (RR interval). The present work focused on relationship between QT and RR and its changes under acute and...

More than four decades passed since sigma receptors were first mentioned. Since then, existence of at least two receptor subtypes and their tissue distributions have been proposed. Nowadays, it is clear, that sigma receptors are unique ubiquitous proteins with pluripotent function, which can interact with so many different classes of proteins. As t...

Haloperidol is an antipsychotic agent that primarily acts as an antagonist of D2 dopamine receptors. Besides other receptor systems, it targets sigma 1 receptors (σ1Rs) and inositol 1,4,5-trisphosphate receptors (IP3Rs). Aim of this work was to investigate possible changes in IP3Rs and σ1Rs resulting from haloperidol treatment and to propose physio...

Background Detailed quantitative analysis of the effect of left ventricle (LV) hypertrophy on myocardial ischemia manifestation in ECG is still missing. The associations between both phenomena can be studied in animal models. In this study, rabbit isolated hearts with spontaneously increased LV mass were used to evaluate the effect of such LV alter...

Anthracyclines use is limited by profound cardiotoxicity. Involvement of miRNAs in anthracycline-induced cardiotoxicity (AIC) is still not completely understood. Thus, the expression of AIC-related microRNAs was determined in rat atria and ventricles after doxorubicin (DOX) and liposomal doxorubicin (L-DOX) administration. Vehiculum, DOX or L-DOX w...

Hypertrophied hearts are known for increased risk of arrhythmias and are linked with reduced ischemic tolerance. However, still little is known about state characterized only by increased left ventricle (LV) mass fraction. Seventeen isolated rabbit hearts with various LV mass were divided into two groups according to LV weight/heart weight ratio (L...

Background: Anthracycline antibiotic doxorubicin (DOX) is a very potent and extensively prescribed chemotherapeutic drug. It is widely utilized in the therapy of variety of haematological and solid tumours, although its administration is commonly accompanied with several severe side effects. The most serious one is a development of dose-dependent...

Heart rate dependency of ventricular repolarization (VR) parameters has been a well known phenomenon for many years. Other contributing factors, such as Mechano-electric Coupling, are still under investigation. In this work, we analyze step response of VR parameters after abrupt change in mechanical end-diastolic load. 10 isolated rabbit hearts wer...

QT prolongation is an independent risk factor for development of ventricular arrhythmias and eventually sudden cardiac death. It is common side effect of various medications, including antipsychotics. It was reported that schizophrenic patients treated with antipsychotics (e.g. haloperidol, olanzapine) manifested QT prolongation. Also, drug-free sc...

Presence of heart rate variability (HRV) in isolated hearts is widely recognized; however, its mechanisms are still subject of debate. One of the possible explanations is that mechanoreceptors in cardiac tissue affect HRV. In order to evaluate possible dependence of HRV on heart mechanoreceptors activated during left ventricle filling, the HRV para...

In this study we show that anti-tumor effect of sulforaphane (SFN) is partially realized through the type 1 inositol 1,4,5-trisphosphate receptor (IP3R1). This effect was verified in vitro on three different stable cell lines and also in vivo on the model of nude mice with developed tumors. Early response (6 hours) of A2780 ovarian carcinoma cells...

Increased oxidative stress is indisputably an important mechanism of doxorubicin side effects, especially its cardiotoxicity. To prevent impairment of non-tumorous tissue and to improve the specificity in targeting the tumor tissue, new drug nanotransporters are developed. In many cases preclinical therapeutic advantage has been shown when compared...

Optical mapping of heart electrical activity in Langendorff-perfused isolated hearts is based on voltage-sensitive dyes, of which the most commonly used one is di-4-ANEPPS. Prolongation of action potential duration by di-4-ANEPPS was reported in isolated cells; however, this phenomenon was not observed in the whole heart model.

Haloperidol is a neuroleptic drug used for a medication of various psychoses and deliria. Its administration is frequently accompanied by cardiovascular side effects, expressed as QT interval prolongation and occurrence of even lethal arrhythmias. Despite these side effects, haloperidol is still prescribed in Europe in clinical practice. Haloperido...

Increased left ventricular (LV) mass leads to higher sensitivity of heart to ischemic injury. This study was focused on comparison of susceptibility of rabbit hearts with different LV mass to short period of ischemia and its modification in consequence of repetition of short ischemic periods. Although higher count of arrhythmias was observed in hea...

Cancer represents the second most frequent cause of mortality in the Czech Republic as well as in all other EU member countries. In 2010, there were 82 606 new cases of malignant tumours reported to National oncology registry of the Czech Republic, which means about 4 % increase as compared to 2009. Taking into account that cardiovascular diseases...

Haloperidol (HP) is used for the symptomatic treatment of psychosis, manic phases, hyperactivity, aggressiveness, and acute delirium. Long-term use leads to various adverse side effects, especially to severe impairment of extrapyramidal nerve tracts and in particular, altered QT interval and increased incidence of arrhytmias. It is believed that cy...

Ischemic and reperfusion injury is a serious condition related to numerous biochemical and electrical abnormalities of the myocardium. It has been repeatedly studied in various animal models. In this study, the production of hydroxyl radicals and electrophysiological parameters were compared in three species. Rat, guinea pig and rabbit isolated hea...

Guinea pigs (Cavia porcellus) were treated with haloperidol (HP), and free radical (FR) and ferric reducing antioxidant power (FRAP) assays were used to determine oxidative stress levels. Furthermore, the superoxide dismutase (SOD), glutathione reductase (GR) and glutathione-S-transferase (GST) activity levels were detected and glucose levels and t...

The influence of antipsychotic drug haloperidol on repolarization defined by QTc interval was analyzed in electrograms of 8 isolated guinea pig hearts. Each experiment consisted of four phases: stabilization (S), first haloperidol administration (H1), washout (W), and second haloperidol administration (H2). QTc was computed according to three corre...

Haloperidol is an older antipsychotic used in the treatment of schizophrenia and in the treatment of acute psychotic states and delirium. Due to its strong central antidopaminergic action, it is classified as a highly potent neuroleptic. However, the usage of typical neuroleptic drugs has been limited by the side effects and toxicity produced by th...