Pulmonary hypertension is a group of diseases characterized by elevated pulmonary artery pressure and pulmonary vascular resistance with significant morbidity and mortality. The most prevalent type is pulmonary hypertension secondary to left heart disease (PH-LHD). The available experimental models of PH-LHD use partial pulmonary clamping by technically nontrivial open-chest surgery with lengthy recovery. We present a simple model in which the reduction of the cross-sectional area of the ascending aorta is achieved not by external clamping but by partial intravascular obstruction without opening the chest. In anesthetized rats, a blind polyethylene tubing was advanced from the right carotid artery to just above the aortic valve. The procedure is quick and easy to learn. Three weeks after the procedure, left heart pressure overload was confirmed by measuring left ventricular end-diastolic pressure by puncture (1.3 ± 0.2 vs. 0.4 ± 0.3 mmHg in controls, mean ± SD, P < 0.0001). The presence of pulmonary hypertension was documented by measuring pulmonary artery pressure by catheterization (22.3 ± 2.3 vs. 16.9 ± 2.7 mmHg, P = 0.0282) and by detecting right ventricular hypertrophy and increased muscularization of peripheral pulmonary vessels. Contributions of a precapillary vascular segment and vasoconstriction to the increased pulmonary vascular resistance were demonstrated, respectively, by arterial occlusion technique and by normalization of resistance by a vasodilator, sodium nitroprusside, in isolated lungs. These changes were comparable, but not additive, to those induced by an established pulmonary hypertension model, chronic hypoxic exposure. Intravascular partial aortic obstruction offers an easy model of pulmonary hypertension induced by left heart disease that has a vasoconstrictor and precapillary component.NEW & NOTEWORTHY We present a new, simple model of a clinically important type of pulmonary hypertension, that induced by left heart failure. Left ventricular pressure overload is induced in rats by inserting a blinded cannula into the ascending aorta via carotid artery access. This partial intravascular aortic obstruction, which does not require opening of the chest and prolonged recovery, causes pulmonary hypertension, which has a precapillary and vasoconstrictor as well as a vascular remodeling component.

• MeSH
• aorta * patofyziologie   patologie   MeSH
• arteria pulmonalis patofyziologie   patologie   MeSH
• cévní rezistence MeSH
• hypertrofie pravé komory srdeční patofyziologie   etiologie   MeSH
• krysa rodu rattus MeSH
• modely nemocí na zvířatech * MeSH
• plicní hypertenze * patofyziologie   etiologie   MeSH
• potkani Sprague-Dawley MeSH
• potkani Wistar MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Pulmonary hypertension is a group of disorders characterized by elevated mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance. To test our hypothesis that combining two drugs useful in experimental pulmonary hypertension, statins and dehydroepiandrosterone sulfate (DHEA S), is more effective than either agent alone, we induced pulmonary hypertension in adult male rats by exposing them to hypoxia (10%O2) for 3 weeks. We treated them with simvastatin (60 mg/l) and DHEA S (100 mg/l) in drinking water, either alone or in combination. Both simvastatin and DHEA S reduced mPAP (froma mean±s.d. of 34.4±4.4 to 27.6±5.9 and 26.7±4.8 mmHg, respectively), yet their combination was not more effective (26.7±7.9 mmHg). Differences in the degree of oxidative stress (indicated by malondialdehydeplasma concentration),the rate of superoxide production (electron paramagnetic resonance), or blood nitric oxide levels (chemiluminescence) did not explain the lack of additivity of the effect of DHEA S and simvastatin on pulmonary hypertension. We propose that the main mechanism of both drugs on pulmonary hypertension could be their inhibitory effect on 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, which could explain their lack of additivity.

• MeSH
• arteria pulmonalis MeSH
• dehydroepiandrosteron farmakologie   terapeutické užití   MeSH
• dehydroepiandrosteronsulfát MeSH
• hypoxie komplikace   farmakoterapie   patologie   MeSH
• krysa rodu rattus MeSH
• plicní hypertenze * farmakoterapie   MeSH
• simvastatin farmakologie   terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

INTRODUCTION: Diabetes is a well-known risk factor in pregnancy. Because maternal diabetes involves oxidative stress that is also induced by chronic hypoxia and can alter vascular function, we sought to determine the effects of chronic maternal hyperglycemia on the fetoplacental vasculature in rats and to compare it with the effects of chronic hypoxia. METHODS: Diabetes was induced in female rats by a streptozotocin injection at a neonatal age. When these animals reached adulthood, their hyperglycemia was confirmed and they were inseminated. Half of them were exposed to hypoxia (10% O2) for the last week before the delivery. One day before the expected date of delivery, one of their placentae was isolated and perfused. RESULTS: Fetoplacental vascular resistance was increased equally by experimental diabetes, chronic hypoxia, and their combination. Fetoplacental perfusion pressure-flow analysis suggested increased resistance in the small vessels in chronic hypoxia and in larger vessels in diabetes. Fetal plasma nitrotyrosine levels, measured as a marker of peroxynitrite (reaction product of superoxide and nitric oxide), mirrored the differences in fetoplacental resistance, suggesting a causative role. Fetoplacental vasoconstrictor reactivity to acute hypoxic stimuli was reduced similarly in all groups. Fasudil, a strong vasodilator agent, reduced fetoplacental vascular resistance similarly in all groups, suggesting that for the observed differences among the groups, the changes in vascular morphology were more important than variances in vascular tone. DISCUSSION: Maternal diabetes increases fetoplacental vascular resistance to a similar extent as chronic hypoxia. These stimuli are not additive. Changes in vascular tone are not responsible for these effects.

• MeSH
• cévní rezistence fyziologie   MeSH
• experimentální diabetes mellitus metabolismus   patofyziologie   MeSH
• gestační diabetes metabolismus   patofyziologie   MeSH
• hypoxie metabolismus   patofyziologie   MeSH
• krysa rodu rattus MeSH
• oxidační stres fyziologie   MeSH
• placenta krevní zásobení   MeSH
• placentární oběh fyziologie   MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.

• MeSH
• Evropská unie MeSH
• lidé MeSH
• mezinárodní spolupráce * MeSH
• molekulární biologie organizace a řízení   trendy   MeSH
• oxidace-redukce MeSH
• reaktivní formy kyslíku chemie   metabolismus   MeSH
• signální transdukce MeSH
• společnosti vědecké MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

• MeSH
• chronická nemoc MeSH
• hypoxie * patofyziologie   MeSH
• maternofetální výměna látek fyziologie   MeSH
• modely nemocí na zvířatech MeSH
• perfuze metody   MeSH
• placenta krevní zásobení   MeSH
• potkani Wistar * MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

Exposure to hypoxia, leading to hypoxic pulmonary hypertension (HPH), is associated with activation of alveolar macrophages (AM). However, it remains unclear how AM participate in this process. There are studies which imply that the AM product monocyte chemoattractant protein-1 (MCP-1) plays an important role. Thus we tested: 1. if the selective elimination of AM attenuates HPH in rats, 2. the correlation of MCP-1 plasmatic concentrations with the presence and absence of AM during exposure to hypoxia, 3. the direct influence of hypoxia on MCP-1 production in isolated AM. We found that experimental depletion of AM attenuated the chronic hypoxia-induced increase in mean pulmonary arterial pressure, but did not affect the serum MCP-1 concentrations. Furthermore, the MCP-1 production by AM in vitro was unaffected by hypoxia. Thus we conclude that AM play a significant role in the mechanism of HPH, but MCP-1 release from these cells is most likely not involved in this process. The increase of MCP-1 accompanying the development of HPH probably originates from other sources than AM.

• MeSH
• alveolární makrofágy sekrece   MeSH
• chemokin CCL2 krev   MeSH
• dichlormethylendifosfonát terapeutické užití   MeSH
• hypoxie komplikace   MeSH
• plicní hypertenze imunologie   prevence a kontrola   MeSH
• potkani Wistar MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Chronic hypoxia induces an increased production of nitric oxide (NO) in pulmonary prealveolar arterioles. Bioavailability of the NO in the pulmonary vessels correlates with concentration of L-arginine as well as activity of phosphodiesterase-5 enzyme (PDE-5). We tested a hypothesis whether a combination of L-arginine and PDE-5 inhibitor sildenafil has an additive effect in reduction of the hypoxic pulmonary hypertension (HPH) in rats. Animals were exposed to chronic normobaric hypoxia for 3 weeks. In the AH group, rats were administered L-arginine during chronic hypoxic exposure. In the SH group, rats were administered sildenafil during chronic hypoxic exposure. In the SAH group, rats were treated by the combination of L-arginine as well as sildenafil during exposure to chronic hypoxia. Mean PAP, structural remodeling of peripheral pulmonary arterioles (%DL) and RV/LV+S ratio was significantly decreased in the SAH group compared to hypoxic controls even decreased compared to the AH and the SH groups in first two measured parameters. Plasmatic concentration of cGMP and NOx were significantly lower in the SAH group compared to hypoxic controls. We demonstrate that NO synthase substrate L-arginine and phosphodiesterase-5 inhibitor sildenafil administered in combination are more potent in attenuation of the HPH compared to a treatment by substances given alone.

• MeSH
• arginin aplikace a dávkování   MeSH
• hypoxie komplikace   farmakoterapie   patofyziologie   MeSH
• kombinovaná farmakoterapie MeSH
• krevní tlak účinky léků   MeSH
• krysa rodu rattus MeSH
• piperaziny aplikace a dávkování   MeSH
• plicní hypertenze farmakoterapie   etiologie   patofyziologie   MeSH
• potkani Wistar MeSH
• puriny aplikace a dávkování   MeSH
• sulfony aplikace a dávkování   MeSH
• synergismus léků MeSH
• vazodilatancia aplikace a dávkování   MeSH
• výměna plynů v plicích účinky léků   MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The vessels on the fetal side of the placenta differ from most other vascular beds except the lungs in that they respond to acute hypoxia by vasoconstriction. An essential role of calcium influx in the mechanism of this hypoxic fetoplacental vasoconstriction (HFPV) has been shown previously. That finding does not, however, exclude the possible involvement of other mechanisms of vascular tone regulation. In this study we tested the hypothesis that Rho-kinase-mediated calcium sensitization is involved in HFPV. We used a model of isolated rat placenta dually perfused (from both the maternal and fetal side) with Krebs salt solution saturated with normoxic and hypoxic gas mixture respectively at constant flow rate. Rho-kinase pathway was inhibited by fasudil (10 μM). We found that fasudil reduced basal normoxic fetoplacental vascular resistance and completely prevented HFPV. This suggests that the activity of Rho-kinase signaling pathway is essential for HFPV.

• MeSH
• cévní rezistence fyziologie   MeSH
• hypoxie metabolismus   patofyziologie   MeSH
• kinázy asociované s rho antagonisté a inhibitory   metabolismus   MeSH
• placenta * krevní zásobení   MeSH
• placentární oběh * fyziologie   MeSH
• těhotenství MeSH
• vápník MeSH
• vazokonstrikce fyziologie   MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH

The aim of our study is a testing of a new pharmacological therapy for intracranial hypertension. We would like to show vasoconstrictive effect of caffeine in cases of traumatic vasoparalysis. We suggest the effect of caffeine may decrease intracranial pressure and improve cerebral perfusion pressure. We will split sixty rats (Wistar) into the three groups - control group, TBI only, and TBI treated with caffeine 10mg/kg (30mg/kg). We will perform bilateral burr holes to monitor ICP and eventually to carry our craniotrauma. We will monitor invasive blood pressure, heart rate, respiration, PaO2, PaCO2, intracranial pressure, cerebral perfusion pressure, and carotid blood flow. Our hypothesis suspects vasocontrictive effect of caffeine and consecutive reduction of CBF by 10 to 15%. We suggest this effect of caffeine may decrease also intracranial pressure and improve cerebral perfusion pressure.

Cílem projektu je ověření účinnosti zcela nové farmakologické terapie u kraniocerebrálního traumatu. Kofein působí jako antagonista adenosinu na A2A receptorech mozkových cév. Šedesát laboratorních potkanů kmene Wistar bude rozděleno do tří skupin. Skupina kontrolní, skupina s kraniotraumatem neléčená a skupina s kraniotraumatem léčená 10mg/kg (30mg/kg) kofeinu. Naše hypotéza předpokládá vazokonstrikční efekt kofeinu a následný pokles mozkového průtoku o 10 až 15%. To by mohlo vést k poklesu intrakraniálního tlaku a zlepšení mozkového perfůzního tlaku v léčené skupině laboratorních zvířat.

• MeSH
• intrakraniální tlak účinky léků   MeSH
• kofein farmakokinetika   MeSH
• kraniocerebrální traumata terapie   MeSH
• modely u zvířat MeSH
• mozkový krevní oběh MeSH
• potkani Wistar MeSH
• receptory adenosinové A2 MeSH
• vazokonstrikce MeSH

• Konspekt
• Farmacie. Farmakologie
• NLK Obory
• neurologie
• farmacie a farmakologie
• biochemie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu IGA MZ ČR

OBJECTIVE: In this study, we present a simple closed head injury model as a two-stage experiment. The height of the weight drop enables gradation of head trauma severity. METHODS: The head injury device consists of three parts and there are three adjustable parameters-weight (100-600 g), height of fall (5-100 cm) and elasticity of the springs. Thirty male Wistar rats underwent monitoring of intracranial pressure with and without induction of the head injury. RESULTS: The weight drop from 45 to 100 cm led to immediate seizure activity and early death of the experimental animals. Severe head injury was induced from 40 cm weight drop. There was 50% mortality and all surviving rats had behavioral deterioration. Intracranial pressure was 9.3 +/- 3.76 mmHg. Moderate head injury was induced from 35 cm, mortality decreased to 20-40%, only half of the animals showed behavioral pathology and intracranial pressure was 7.6 +/- 3.54 mmHg. Weight drop from 30 cm caused mild head injury without mortality and neurological deterioration. Intracranial pressure was slightly higher compared to sham group- 5.5 +/- 0.74 mmHg and 2.9 +/- 0.81 mmHg respectively. CONCLUSION: This model is an eligible tool to create graded brain injury with stepwise intracranial pressure elevation.

• MeSH
• intrakraniální tlak * MeSH
• krysa rodu rattus MeSH
• poranění mozku * MeSH
• potkani Wistar MeSH
• teoretické modely MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH