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Tikslas: Ištirti dviskiaučių ginkmedžių lapų tinktūros (GT) poveikį žiurkės širdies mitochondrijų funkcijoms mechanizmą. Uždaviniai: 1) Ištirti GT poveikį žiurkės širdies mitochondrijų vidinės membranos laidumui. 2) Ištirti GT poveikį žiurkės širdies mitochondrijų kvėpavimui po girdymo GT. 3) Įvertinti laisvųjų deguonies junginių susidarymą žiurkės širdies mitochondrijose po girdymo GT. Tyrimo metodai: Eksperimentiniame darbe buvo tiriamas dviskiaučių ginkmedžių lapų tinktūros (GT) poveikis žiurkės širdies mitochondrijų funkcijoms. Tyrimams naudojami Wistar veislės žiurkių suaugę patinėliai. Eksperimentinis gyvūnėlis užmigdomas anglies dioksido dujomis ir nutraukiamas stuburo kanalas kaklo srityje (leidimo, atlikti laboratorinius bandymus su gyvūnais, Nr.0006). GT poveikio žiurkės širdies mitochondrijų funkcijų tyrimui buvo pasirinkti du eksperimentiniai modeliai: 1) Tyrimai in vitro. Žiurkės širdies mitochondrijos izoliuojamos diferencinio centrifugavimo būdu, GT poveikis žiurkės širdies mitochondrijų oksidacinio fosforilinimo sistemai buvo tiriamas naudojant spektrofotometrinį bei poliarografinį metodus; 2) Tyrimai in vivo. Wistar veislės žiurkių patinėliai 7 dienas buvo girdomi GT (54 ar 108 μl/parai). Po to izoliuojamos širdies mitochondrijos ir vertinamas GT poveikis širdies mitochondrijų kvėpavimo parametrams bei H2O2 susidarymui širdies mitochondrijose. Rezultatai: Tyrimuose in vitro, nustatėme, kad GT didina mitochondrijų vidinės membranos laidumą dėl protonoforinių... [toliau žr. visą tekstą] / Aim: To investigate the mechanism of the effect of Ginkgo leaves tincture (GT) on mitochondrias functions. The objectives: 1) To investigate the impact of GT on permeability properties of mitochondrial inner membrane; 2) To investigate GT effect on rat hart mitochondrial respiration after oral treatment with GT; 3) To evaluate reactive oxygen species production in rat harts mitochondrias after oral GT administration. Methods: In this research work we investigated the impact of Ginkgo leaves tincture (GT) on rat hart mitochondrial functions. Male adult Wistar rats were used. The experimental animal was taken to sleep by carbon dioxide gas and its spinal canal had been broken in the neck zone (number of permission of laboratory testing on animals, No. 0006). We chose two experimental models of research on GT effects on rat heart mitochondrial functions: 1) In vitro studies. Rat heart mitochondrias were isolated by differential centrifugation, the impact of GT on rat heart mitochondrial oxidative phosphorilation system was evaluated by spectrophotometric and oxygraphic methods. 2) In vivo studies. Male adult Wistar rats were given GT (54 or 108 μl/day) for 7 days. After that mitochondrias were isolated and GT effects on mitochondial respiration and H2O2 production were evaluated. Results: In vitro studies have shown that GT increases permeability of mitochondrial inner membrane, due to higher permeability of protons. This effect is related to impact on ADP/ATP translocator and... [to full text]

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Ten trained male track athletes (VO2max = 64.7 ml&middot;kg&middot;min -1) performed three workouts (conditions) with repeated 400-m runs. The intensity and number of repetitions varied among conditions. Condition 1 consisted of two all-out 400-m runs. Condition 2 was 4 x 400-m runs with the first three reps performed 4 s slower than condition 1 and the 4 th rep was all-out. Condition 3 consisted of 8 x 400-m runs with the first seven reps performed 8 s slower than condition 1 and the 8th rep was all-out. Dependent variables were HR, blood lactate and run time for the final rep in each condition. Peak HRs for the last run were 201, 194, 189 beats&middot;min-1 for conditions 1, 2 & 3 respectively, and were not significantly different. Blood lactate values measured 4 min after the last run were 16.6, 17.8 and 17.1 mmol&middot;L -1 in conditions 1, 2 and 3 respectively, and were not significantly different. Run times for conditions 1 (55.2 s), 2 (56.9 s) and 3 (61.5 s) were significantly different (P < 0.05). The decline in performance was greatest in condition 3. The three conditions challenged the anaerobic system with similar peak values for lactate and heart rate during the final run.

Chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF) patients show a marked reduction in exercise capacity compared to that of healthy age-matched individuals. While inadequate gas exchange and resulting hypoxemia appears as the primary factor in COPD, an impaired cardiac output is the predominant explanation for the reduced oxygen delivery in CHF. However, the extent of the contributions of other systemic factors remains unclear. In light of the potential interactions between cardiac output (Qc) and pulmonary hyperinflation, there is surprisingly little data thus far on ventilatory constraints in CHF and on the role of blood flow delivery in COPD which may further limit the exercise capacity. Thus, the purpose of this study was to compare the slope of the Qc versus oxygen uptake (VO2) response through several submaximal cycling loads in patients with moderately severe COPD and with that of moderate to severe CHF patients as well as age-matched healthy control subjects (CTRL). Also examined was the possibility that ventilatory constraints such as dynamic hyperinflation contribute to an abnormal stroke volume response in both diseases. Cardiac output was measured using the CO 2-rebreathing equilibrium technique during baseline conditions and cycling at 20, 40 and 65% of peak power in 17 COPD (Age: 64 +/- 8 yrs; FEV 1/FVC: 37 +/- 11%; FEV1: 41 +/- 15 % predicted), 10 CHF (Age: 57+/- 10 yrs; FEV1/FVC: 73.8 +/- 5.6%; FEV 1: 93 +/- 13% predicted) and 10 age-matched CTRL subjects. Inspiratory capacity (IC) was also measured for the determination of dynamic hyperinflation during the steady state exercise bouts. The results indicate that while the absolute Qc values are lower in COPD and in CHF than in CTRL during 65% peak power cycling (11.30 +/- 2.38 vs 12.40 +/- 2.08 vs 15.63 +/- 2.15 L&bull;min-1 respectively, p &lt; 0.01), likely due to their lower exercise metabolic demand. The Qc/VO2 response to increasing levels of exercise intensity was lower or normal in CHF patients compared to CTRL, while normal or hyperdynamic in most COPD patients. Indeed, the majority of patients with COPD exhibited Qc/VO2 slopes greater than 7.0, which may be indicative of a peripheral muscle bioenergetic disturbance that may drive the need for greater oxygen delivery, and thus result in an exaggerated central circulatory response.