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Cilj istraživanja bio je da ispita efekte protokola usmerenog izazivanju pretreniranosti na kardiodinamiku, koronarni protok i oksidativni stres u koronarnom efluentu izolovanog srca pacova. Pacovi su podeljeni u tri grupe (kontrole, umereno trenirani, preterano često trenirani pacovi) i podvrgnuti različitom trenažnom protokolu tokom 9-12 nedelja. Nakon žrtvovanja životinja, srce je izolovano i perfundovano na Langendorf aparatu, a tokom koronarne autoregulacije (koronarni perfuzioni pritisak 40-120 mmHg) praćeni su sledeći kardiodinamski parametri leve komore: maksimalna i minimalna stopa promene pritiska, sistolni i dijastolni pritisak, srčana frekvenca. Koronarni protok meren je floumetrijski, a u koronarnom efluentu određeni su nivoi parametara oksidacionog stresa (superoksid anjon radikal, vodonik peroksid, nitriti, lipidni peroksidi). Primenjeni eksperimentalni protokol plivanja nije indukovao pretreniranost kod pacova. Preterano često plivanje dovelo je do pozitivnih promena u kardiodinamici i koronarnom protoku izolovanih srca pacova, u većoj meri od umerenog trenažnog protokola. Rezultati naše studije potvrđuju pozitivne efekte redovnog aerobnog treninga na srce, i pokazuju da često vežbanje, ukoliko je intenzitet vežbanja umeren, nema štetne efekte na kardiodinamiku. U poređenju sa kontrolama, srca umereno treniranih, a posebno često treniranih pacova, produkovala su niže nivoe prooksidanata. Ovakvi rezultati verovatno su posledica bolje srčane funkcije, kao i aktivnosti antioksidativnog sistema kod često treniranih pacova. Obzirom na izostanak dijagnoze pretreniranosti, naša studija ne doprinosi značajno rasvetljavanju veze između ovog fenomena, funkcije srca i uloge oksidativnog stresa u ovom sindromu, međutim, ona daje važne smernice za dizajniranje budućih plivačkih trenažnih protokola, posebno onih koji za cilj imaju indukovanje pretreniranosti. Takođe, naša studija doprinosi saznanjima o efektima različitih trenažnih protokola na kardiodinamiku i redoks status u srcu. The aim of the research was to explore the effects of the training protocol designed for overtraining induction on cardiodynamics, coronary flow and oxidative stress in coronary effluent from an isolated rat heart. The rats were divided into three groups (control, moderately trained, overfrequently trained rats) and subjected to different training protocol during 9-12 weeks. After sacrificing animals, hearts were excised, isolated and perfused on a Langendorf apparatus, and following cardiodynamic parameters of the left ventricle were measured during coronary autoregulation (coronary perfusion pressure 40-120 mmHg): maximal and minimal rate of pressure change, systolic and diastolic pressure, heart rate. Coronary flow was measured flowmetrically, and in coronary effluent following parameters of oxidative stress were measured: superoxide anion radical, hydrogen peroxide, nitric oxide, lipid peroxides. Applied experimental protocol did not induce overtraining in rats. Overfrequent swimming lead to positive changes in cardiodynamics and coronary flow, in a greater rate than moderate training. The results of our study confirm positive effects of regular aerobic exercise training on the heart, and show that frequent exercise, if the intensity of exercise is moderate, it is not harmful for the heart. In comparison with controls, hearts of rats trained moderately, and especially hearts of overfrequently trained rats, produced lower levels of prooxidants. Those results are probably a consequence of better cardiac function, as well as activity of antioxidative system in overfrequently trained rats. Given the lack of diagnosis of overtraining, our study does not contribute significantly to shed light on the relationship between this phenomenon, function of the heart and the role of oxidative stress in this syndrome, however, it provides important guidance for designing future swimming training protocols, especially those that aim to induce overtraining. Also, our study contributes to knowledge about the effects of different protocols of training on cardiodynamics and redox status of the heart.

Cilj. Evaluacija efekata akutne i hronične administracije nandrolona na funkciju miokarda i oksidacioni stres izolovanog srca pacova Metode. Istraživanje je obuhvatilo 240 pacova i životinje su bile podeljene upodenjenih u 8 grupa, od kojih su 4 grupe deo akutne, a ostale 4 grupe su deo hronične serije ksperimenata gde je svaka grupa podeljena u tri podrupe. U okviru akutne serije eksperimeneta postojale su 4 grupe: 1. kontrolna grupa (perfuzija Krebs- Hensenleit-ovim fiziološkim rastvorom),2.perfuzija nandrolonom u dozi 1 μM/L; 3. perfuzija nandrolonom u dozi 10 μM/L;4. perfuzija nandrolonom u dozi 100μM/L;Hronična serija eksperimenata je bil podeljena na 4 grupe:1.životinje koje se ne treniraju i ne primaju nandrolon; 2.životinje koje se treniraju plivanjem i ne primaju nandrolon;3.životinje koje se ne treniraju i primaju nandrolon u vidu depo preparata (nandrolone decanoate - 20 mg/kg, s.c., u trajanju od 4 nedelje). 4.životinje koje se treniraju plivanjem i primaju nandrolon u vidu depo preparata Pratili su se kardiodinamski paramteri (dp/dt max, dp/dt min, SLVP, DLVP, HR i CF) markeri oksidacionog stresa (TBARS, NO2-, O2-, H2O2) Rezultati. Rezultati istraživanja su prikazani na 1 tabeli i 60 grafikona. Akutna serija eksperimenta je pokazala da sa porastom primenjene doze nandrolon dekanoata dolazi do značajnijeg smanjenja najvažnijih kardiodinamskih parametara bez uticaja na markere oksidacionog stresa. Hronična serija eksperimenta je pokazala da nandrolon dekanoat zajedno sa dugotrajnim vežbanjem smanjuje vrednosti svih ispitivanih kardiodinamskih parametara. Zaključak. Akutno primenjeni nandrolon dekanoat ima kardiodepresivni uticaj koji najverovatnije ne uključuje oksidaciona oštećenja. Dugotrajni trening visokog inteziteta (sa ili bez upotrebe anabolika) negativno utiče na funkciju miokarda. Nandrolon dekanoat u prisustvu fizičkog opterećenja ispoljava manji pro- oksidacioni efekat, u odnosu na odsustvo treninga kao mogućeg generatora enzima iz sistema antioksidativne zaštite. Objective. Evaluation of the effects of acute and chronic administration of nandrolone on myocardial function and oxidative stress in isolated rat heart Methods. The study included 240 rats divided in 8 groups: 4 which are part of the аcute experiments and other 4 groups - part of chronic series of experiments where each group was divided into three subgroups. Acute series of experiments consisted 4 groups: 1. control group (perfusion of Krebs-Hensenleit's saline), 2. perfusion with nandrolone decanoate in a dose of 1 uM/L; 3. perfusion with nandrolone decanoate in a dose of 10 uM/L 4. perfusion with nandrolone decanoate in a dose of 100 uM/L. Chronic series of experiments were divided into 4 groups: 1.animals that do not train and not treated with nandrolone; 2. animals that practice swimming, and treated with nandrolone; 3.animals that do not train and receive nandrolone in the depo form (nandrolone decanoate - 20 mg / kg, sc, for a period of 4 weeks). 4.animals that practice swimming and receive nandrolone in the form of depo. Cardiodynamic parameteres (dp / dt max dp / dt min, SLVP, DLVP, HR and CF) and markers of oxidative stress (TBARS, NO2 -, O2 -, H2O2) were determinated. Results. The research results are presented in 1 table and 60 graphs. Acute series of experiments showed that with the increase of the applied dose of nandrolone decanoate there were considerable decline of the most important cardiodynamic parameters with no effect on oxidative stress markers. Chronic series of experiments showed that nandrolone decanoate together with long-term exercise reduces the values of all examined cardiodynamic parameters. Conclusion. Acutely applied nandrolone decanoate has cardiodepressive impact that probably does not include oxidative damage. Long-term high-intensity training (with or without the use of anabolic steroids) has a negative impact on myocardial function. Nandrolone decanoate in the presence of physical activity exerts a smaller pro-oxidative effect, in relation to the lack of training as a potential generator of antioxidant enzyme protection.

Cilj ove studije je bio da ispita efekate prekondicioniranja ishemijom i efekte akutne administracije različitih lekova iz grupe inhibitora protonske pumpe kao farmakoloških agenasa u modelu prekondicioniranja na funkcionisanje miokarda i koronarnu cirkulaciju izolovanog srca pacova kao i moguću ulogu oksidacionog stresa. Metode. U studiji je analizirano 60 pacova (Vistar albino soj, muški pol, starosti 8 nedelja, telesne mase 250±50g) kojima se izolovalo srce i perfundovalo metodom retrogradne perfuzije po Langendorfu (Langendorff apparatus, Experimetria Ltd, 1062 Budapest, Hungary) pri konstantnom koronarnom perfuzionom pritisku od 70 sm H2O. Istraživanje je bilo podeljeno u pet (5) eksperimentalnih grupa. Vrednost koronarnog protoka su određivane floumetrijski. U levoj komori su kontinuirano praćeni parametri funkcije leve komore: a) dp/dt max - maksimalna stopa promene pritiska u levoj komori, b) dp/dt min - minimalna stopa promene pritiska u levoj komori, v) SLVP - sistolni pritisak leve komore, g) DLVP - dijastolni pritisak leve komore i đ) HR - srčana frekvenca. U uzorcima koronarnog venskog efluenta spektrofotometrijskim metodama su određivani sledeći markeri oksidacionog stresa: indeks lipidne peroksidacije – meren kao TBARS, azot monoksid u formi nitrita (NO2), superoksid anjon radikal (O2 -), i vodonik peroksid (H2O2). Rezultati. Rezultati istraživanja su prikazani na 10 tabela i 50 grafikona. Sumarno posmatrano, ishemijsko prekondicioniranje je najpozitivniji efekat ostvarilo u očuvanju perfuzije miokarda i srčane frekvence, dok je prekondicioniranje farmakološkim agensima (lekovima iz grupe inhibitora protonske pumpe) pokazalo bolje rezultate u očuvanju oba parametra kontraktilnosti. Kardiodinamski efekti svih ispitivanih lekova iz grupe IPP nisu bili posredovani oksidacionim stresom. Zaključak. Obe vrste prekondicioniranja su pokazale pozitivan efekat na funkcionalni oporavak miokarda, s tim što je taj uticaj u slučaju farmakološkog prekondicioniranja bio dominanatan na očuvanje kontraktilne sile, dok je u slučaju ishemijskog prekondicioniranja efekat bio fokusiran na očuvanje koronarne reaktivnosti srca. Prilikom međusobnog poređenja ostvarenih efekata ispitivanih IPP, možemo zaključiti da se najznačajniji pozitivni efekat na oporavak miokarda sreće u slučaju omeprazola i pantoprazola. The aim of this study was to investigate the effect of applying preconditioning ischemia and effects of acute administration of different drugs from the group of proton pump inhibitors as pharmacological agents in the model of preconditioning on myocardial function and coronary circulation in isolated rat heart as well as the possible role of oxidative stress. Methods. Sixty rats (Wistar, albino, males, aged 8 weeks, body weight 250±50 g) had the hearts isolated and perfused by using retrograde perfusion method according to Lagendorff (Langendorff apparatus, Experimetria Ltd, 1062 Budapest, Hungary) at constant coronary perfusion pressure of 70 cm H2О. The research included five (5) experimental groups. The values of coronary flow were determined fluorometrically. The next parameters of left ventricle function were continuously followed: a) dp/dt max – maximum rate of pressure change in the left ventricle, b) dp/dt min - minimum rate of pressure change in the left ventricle c) SLVP – systole left ventricle pressure, d) DLVP - diastole left ventricle pressure and e) HR – heart rate. In the samples of coronary venous effluent the following parameters were determined using spectrophotometric methods: lipid peroxidation index – measured as TBARS, nitrogen monoxide in the form of nitrite (NO2), superoxide anion radical (O2 -), and hydrogen peroxide (H2О2). Results. The research results are presented in 10 tables and 50 graphs. In summary, ischemic preconditioning is the most positive effect achieved in the preservation of myocardial perfusion and heart rate, while the preconditioning pharmacological agents (drugs from the group of proton pump inhibitors) showed better results in terms of both parameters contractility. Effects on cardiodynamic of all the tested drugs from the group of PPIs were not mediated by oxidative stress. Conclusion. Both types of preconditioning showed positive effect on functional recovery of the myocardium, with the impact in the event of pharmacological preconditioning that was most dominant on the preservation of contractile force, while in the case of ischemic preconditioning effect was focused on preservation of coronary heart reactivity. When mutual comparison of actual effects of tested IPP, we can conclude that the most important positive effect on the recovery of myocardial we noted in the case of omeprazole and pantoprazole.