RESUMO
Intraocular pressure (IOP) and eye hydrodynamics (aqueous outflow easiness rate (C) and moisture chamber production (F)) were studied in 9 adult volunteers subjected to the hypogravity effects of head-down tilt (HDT) at -15° to the horizontal plane. The volunteers stayed in the horizontal and tilted positions for 10 minutes. IOP was measured according to Maklakov (tonometer 5 g), C and F - according to Nesterov (simplified tonography). In parallel, heart rate (HR) and systolic and diastolic blood pressures (SBP and DBP) were measured in the sitting, lying and tilted positions. In HDT IOP rose 10.3 % (p < 0.05) and C reduced 60 % (p < 0.05); F showed an uncertain trend down by 59 % (p > 0.05). Increase of the Bekker coefficient by 168 % (p < 0.05) could testify interconnection of the increased IOP and impaired moisture outflow. Moreover, in HDT DBP showed a rise while HR decreased. These results suggest that during brief tilt- down IOP increases not only because of a greater filling of the choroid vessels, but also because of retarded outflow of the intraocular fluid. The downward trend in fluid production can be a compensatory reaction to increased'IOP.
Assuntos
Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Pressão Intraocular/fisiologia , Fenômenos Fisiológicos Oculares , Adulto , Humor Aquoso/fisiologia , Pressão Sanguínea , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Humanos , Hipogravidade/efeitos adversos , MasculinoRESUMO
The purpose of the research: To study the water balance of lung and NO level in blood in experimental autoimmune encephalomyelitis combined with capsaicin blockade of vagus nerve. Methods: Experiments were conducted on 47 adult (16-week-old) male rats weighing 220-280 g. To simulate the experimental autoimmune encephalomyelitis (EAE) rats were subcutaneously injected with encephalitogenic mixture in complete Freund's adjuvant (0.2 ml; the content of inactivated Mycobacterium tuberculosis was 5 mg/ml) at the rate of 100 mg of homologous spinal cord homogenate per animal. Сapsaicin blockade was performed by bilateral application of 50 uM capsaicin («Sigma¼) on the neck portions of vagus nerves. The animals were divided into 4 groups: intact rats - control group1; rats with EAE; rats with capsaicin application on vagus nerve + EAE; sham operated rats subjected to vagus nerves allocation without the subsequent capsaicin application + EAE - control group 2. The next parameters were detected: the content of nitric oxide in blood plasma; protein content in broncho-alveolar lavage fluid; lung water balance indices including the amount of total, extra- and intravascular fluid and blood supply of lungs, which were calculated based on wet and dry lung mass and the hemoglobin content in blood and lung tissue determined by hemiglobincyanide method. Results: It was found that EAE is accompanied by an increase of total fluid, extravascular fluid (EVF) and blood supply of lungs on the background of increasing content of nitric oxide in arterial (art) and venous (ven) blood. In EAE and its combination with bilateral capsaicin blockade of vagus nerve a strong negative correlation between the NOart / NOven coefficient and EVF amount was found out. The blockade of capsaicin-sensitive vagal afferents normalized lung water balance impaired in EAE and restored the levels of nitric oxide in blood plasma. Conclusion: The obtained results suggest that capsaicin-sensitive vagal afferents with NO-ergic mechanisms involvment take part in the development of pulmonary hyperhydration during experimental autoimmune encephalomyelitis.
Assuntos
Capsaicina/efeitos adversos , Encefalomielite Autoimune Experimental , Pulmão , Óxidos de Nitrogênio , Nervo Vago , Equilíbrio Hidroeletrolítico , Animais , Capsaicina/farmacologia , Encefalomielite Autoimune Experimental/sangue , Encefalomielite Autoimune Experimental/imunologia , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Óxidos de Nitrogênio/sangue , Óxidos de Nitrogênio/imunologia , Ratos , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/imunologiaRESUMO
In rats with ligation of both common carotid arteries in condition of bilateral capsaicin blockade of vagus nerve the metabolic functions of the lungs associated with their participation in the regulation of hemostasis, lipid composition of blood plasma and lung surfactant were investigated. It is shown that cerebral ischemia is accompanied by changes in the fractional composition of phospholipids in both arterial and venous blood, as well as in pulmonary surfactant, and the decrease of the lung hypocoagulation effect. The phagocytic activity of alveolar macrophages (as one of the factors involved in surfactant lipids metabolism) in brain ischemia is reduced. After the blockade of capsaicin-sensitive vagal afferents the changes in surfactant and plasma phospholipids caused by cerebral ischemia, are abolished, hypocoagulation effect of lung restores, but the functional activity of macrophages remains decreased. These findings suggest that capsaicin-sensitive vagal afferents are involved in the development of disregulatory disorders of lung metabolic function in cerebral ischemia.
Assuntos
Isquemia Encefálica/metabolismo , Capsaicina/farmacologia , Pulmão/metabolismo , Bloqueio Nervoso , Nervo Vago/efeitos dos fármacos , Animais , Isquemia Encefálica/sangue , Isquemia Encefálica/fisiopatologia , Macrófagos/metabolismo , Masculino , Fosfolipídeos/sangue , Surfactantes Pulmonares/metabolismo , Ratos , Nervo Vago/fisiologiaRESUMO
Direct effects of circulating blood microparticles on fibrin formation and structure were studied. Clots made from platelet-free plasma and from microparticle-depleted plasma obtained by filtration was studied in parallel, including clots from the microparticle-depleted plasma replenished with phospholipids. Fibrin formation was induced by exogenous thrombin without Ca2+ to prevent formation of endogenous thrombin and exclude indirect kinetic effects of microparticles related to thrombin generation. In the presence of natural microparticles or exogenous phospholipids the maximal turbidity of fibrin clots was significantly smaller, indicating structural distinctions from the clots formed in the absence of microparticles. Scanning electron microscopy and confocal microscopy showed that clots formed from platelet-free plasma, i. e. in the presence of microparticles, unlike clots from the microparticle-depleted plasma, contained 0.1-0.5-µm-large CD61-positive granules associated with fibrin fibers that were identical to the particles found on the surface of filters used for microparticle removal. The results show that platelet-derived microparticles bind to fibrin and affect its structure. The revealed interactions of cell-derived microparticles with fibrin highlight a previously unknown role of microparticles in hemostasis and thrombosis as constituents and modulators of a fibrin clot structure.
Assuntos
Coagulação Sanguínea , Plaquetas/metabolismo , Micropartículas Derivadas de Células/metabolismo , Fibrina/metabolismo , Plaquetas/citologia , Micropartículas Derivadas de Células/ultraestrutura , Fibrina/ultraestrutura , Humanos , Integrina beta3/genética , Integrina beta3/metabolismo , Ligação ProteicaRESUMO
The dynamics of rat's swimming test with a load after 10 daily deprivation of light or dark were investigated. It was established that in the control group in nature illumination daily physical swimming with a load to full exhaustion from the first to the third day of the experiment, there was an increase of active swimming time indicator followed by stabilization. In groups of animals kept before bringing swimming test in a day and night lighting or darkening around the clock, there was an increase in swimming time only on the first day of the experiment, and the next days there was a decrease of efficiency. After a five-day cycle of the swimming load the level of lactate in the blood of control animals was increased, and experienced - has not changed in comparison with the intact, not subjected to any stress.
Assuntos
Escuridão/efeitos adversos , Ácido Láctico/sangue , Esforço Físico , Estresse Psicológico/fisiopatologia , Natação , Animais , Masculino , Ratos , Ratos Wistar , Estresse Psicológico/etiologiaRESUMO
It is known that intracranial hemorrhage (ICH) is accompanied by the development of neurogenic pulmonary edema and insufficiency of surfactant function. The present study was undertaken for evaluation of the role of vagal afferents in the mechanisms of ICH effects on pulmonary surfactant and water balance of the lung. We explored the surface activity and biochemical composition of surfactant, as well as blood supply, total, intravascular and extravascular fluid content in lung after ICH, simulated by intraventricular administration of autologous blood against the background of bilateral blockade of capsaicin-sensitive vagal affere its. The blockade was caused by the capsaicin application (50 mcmol) on the cervical part of the nerves. Intracerebralhemorrhage was accompanied by the decrease of surfactant activity which appeared by the enhancement of minimal, maximal and static surface tension of bronchoalveolar lavage fluid (BAL), the reduction of total phospholipids including their main fraction phosphatidylcholine, the increase of lysophosphatidyicholine content and hyperhydration of the lung. The level of total proteins in BAL elevated, confirmed the enhanced permeability of the alveolar-blood barrier. The exhaustion of neuropeptides in capsaicin-sensitive vagal afferents led to the partial restoration of surface active properties of lung, normalization of phospholipids and protein contents and water balance parameters. The obtained results suggest that capsaicin-sensitive vagal afferents play a pivotal role in the disturbances of surfactant function and water balance of the lung after ICH.
Assuntos
Capsaicina/administração & dosagem , Hemorragia Cerebral/fisiopatologia , Edema Pulmonar/fisiopatologia , Surfactantes Pulmonares/metabolismo , Animais , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Humanos , Pulmão/metabolismo , Pulmão/fisiopatologia , Fosfolipídeos/metabolismo , Edema Pulmonar/complicações , Edema Pulmonar/tratamento farmacológico , Ratos , Nervo Vago/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/fisiologiaRESUMO
It is shown that the surface active properties of lung under experimental diabetes mellitus was decreased on the background of increased LPL content in alveolar space. Surfactant changes correlated with the level of glucose, glycosylated hemoglobin and 11-oxycorticosteroids in blood. The obtained results indicate that the degree of impairment in the pulmonary surfactant system in alloxan diabetes depends on the resistance or susceptibility of animals to stress.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Pulmão/metabolismo , Surfactantes Pulmonares/metabolismo , Estresse Fisiológico , Corticosteroides/sangue , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/patologia , Hemoglobinas/metabolismo , Pulmão/patologia , RatosRESUMO
For the first time in skeletal muscle, the sphingolipid profile and key enzymes involved in the generation of ceramide in cells were investigated in simulated microgravity. It was found that, in C57B1/6 mice, the 4-day hindlimb unloading, in addition to reducing the mass of m. soleus, leads to the ceramide accumulation (3-fold) and the decrease of sphingomyelin content in this muscle (7.2-fold), as well as to the increase (2.7-fold) of protein level of acid sphingomyelinase. In a loaded m. biceps brachii the amount of ceramide is also enhanced, but both the amount of sphingomyelin and sphingomyelinase, as well as the muscle mass do not change, while the level of serine palmitoyltranspherase becomes significantly lower than in control mice. Taking into account the negative effects of ceramide in skeletal muscle (insulin resistance, inhibition of protein synthesis and increase of its decay) we can assume that sphingolipid mechanisms may be involved in the development of structural and functional abnormalities of skeletal muscle under conditions of weightlessness.
Assuntos
Ceramidas/metabolismo , Músculo Esquelético/química , Esfingomielinas/metabolismo , Simulação de Ausência de Peso , Animais , Ceramidas/análise , Membro Anterior , Membro Posterior , Elevação dos Membros Posteriores , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/fisiologia , Serina C-Palmitoiltransferase/análise , Serina C-Palmitoiltransferase/metabolismo , Esfingomielina Fosfodiesterase/análise , Esfingomielina Fosfodiesterase/metabolismo , Esfingomielinas/análiseRESUMO
Weightlessness produces adaptive and maladaptive changes in the respiratory system. We assessed the effects of 30-day antiorthostatic hanging as a model of microgravity on the water balance in the lungs and surface activity and phospholipid composition of pulmonary surfactant in C57Bl/6 mice. Long-term antiorthostatic hanging increased water content in the lungs and reduced surface-active properties of the surfactant. This was accompanied by an increase in the content of alveolar phospholipids and changes in their fractional composition (increase in the relative content of lysophosphatidylcholine and phosphatidylethanolamine).
Assuntos
Pulmão/química , Surfactantes Pulmonares/análise , Água/análise , Ausência de Peso , Animais , Densitometria , Lisofosfatidilcolinas/análise , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidiletanolaminas/análise , Fosfolipídeos/análise , Alvéolos Pulmonares/química , Estatísticas não ParamétricasRESUMO
White male rats with the body mass of 180-220 grams were distributed into the open-field active (presumably stress-resistant) and open-field inactive (presumably stress vulnerable) groups for a 10-day experimental suspension with the purpose to evaluate the surfactant activity in bronchoalveolar lavages, total phospholipids and their fractions, and water balance in the lung. In modeled microgravity, augmented blood filling of the rat's lung increases the alveolar phospholipid content and alters the phospholipid fractional composition in the pulmonary surfactant. Ten-day suspension raises pulmonary surfactant activity to a greater extent in stress-resistant animals rather than in their stress vulnerable peers.
Assuntos
Pulmão/metabolismo , Surfactantes Pulmonares/metabolismo , Estresse Psicológico/metabolismo , Ausência de Peso , Animais , Líquido da Lavagem Broncoalveolar , Masculino , Fosfolipídeos/metabolismo , Alvéolos Pulmonares/metabolismo , Ratos , Fatores de Tempo , Água/metabolismoRESUMO
The aim of the present study was to investigate the effect of chronic exposure to immobilization and psychosocial stress on surface activity, biochemical composition of pulmonary surfactant and lung fluid balance of rats with different stress-resistance. It is shown that both types of stress lead to elevation of lysophospholipids level and decrease of surface-active properties of pulmonary surfactant, more prominent in stress-vulnerable rats. Blood supply was decreased and extravascular fluid was increased under the psychosocial stress only in stress-vulnerable animals, in all rest cases the blood supply was increased and the content of extravascular fluid was not changed. Surfactant alteration was coupled on the level of 11-OCS in the blood and amount of fluid in the lungs. The obtained results indicate that different degree of impairment in the pulmonary surfactant system during immobilization and psychosocial conflicts depends on different resistance to emotional stress.
Assuntos
Pulmão , Lisofosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Estresse Fisiológico , Estresse Psicológico , Animais , Líquido da Lavagem Broncoalveolar , Imobilização , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Masculino , Ratos , Estresse Fisiológico/genética , Estresse Psicológico/genética , Propriedades de Superfície , Tensoativos/metabolismoRESUMO
The dependence between variation of erythrocyte phospholipid composition and stress resistance was studied in chronic experiment on nonline male albino rats, previously differed by their behavior in the 'open field' test. A significant exhausting of membrane pool by the basic classes of phospholipids was registered under influence of 2 hours daily immobilization during 5, 10, 20, 30 days, however, their metabolism for resistant and predisposed to stress animals flows variously.
Assuntos
Membrana Eritrocítica/metabolismo , Imobilização , Lipídeos de Membrana/metabolismo , Estresse Fisiológico , Animais , Comportamento Animal , Masculino , Ratos , Fatores de TempoRESUMO
The dependence between variation of prefrontal cortex phospholipid composition and stress-resistance was studied in chronic experiment on nonline male albino rats, previously differed by their behavior in the "open field" test. A significant lack of basic classes of phospholipids was registered in prefrontal cortex under the effect of a 2-hour daily immobilization during 5, 10, 15, 30 days. We proposed criteria of individual stress-resistance. These criteria could be interesting for improvement of stability under extreme conditions with the aid of correction of neuronal biogenesis.
Assuntos
Fosfolipídeos/metabolismo , Córtex Pré-Frontal/metabolismo , Estresse Psicológico/metabolismo , Adaptação Fisiológica , Animais , Imobilização , Masculino , RatosRESUMO
In chronic experiment on male albino rats divided into active and passive groups according to their behavior in "open field" test significant differences in character of lung metabolic activity upon biogenic amines were found out. In both groups the highest level of histamine in arterial and venous blood was registered on the 5th day, 5-hydroxytriptamine--on the 10-20 days and catecholamine--on the 20th day of the experiment. On the 5th day lungs pf passive rats uptaked catecholamines from blood whereas lungs of active ones put in into blood. Histamine and 5-hydroxytriptamine uptake took place on the 5th day only in active rats, but on the 10th only lungs of passive ones absorbed 5-hydroxytriptamine from blood. Intergroup differences of lung metabolic activity upon histamine and 5-hydroxytriptamine were removed on the 20th day. Lung monoamine oxydase activity was significantly increased in active rats and decreased in passive ones in all periods of experiment.
Assuntos
Aminas Biogênicas/metabolismo , Pulmão/metabolismo , Monoaminoxidase/metabolismo , Estresse Psicológico/metabolismo , Animais , Imobilização , Masculino , Ratos , Fatores de TempoRESUMO
In this work, we investigated surface active properties and biochemical composition of pulmonary surfactant under emotional stress in condition of neuropeptides pool exhaustion in capsaicin-sensitive afferents of the vagus nerve. It is shown that stress is accompanied by decrease of lung surface active properties and increase of total phospholipids content as result of phosphatidylcholine and lysophospholipid fraction rise. After capsaicin application on the cervical part of the right vagus nerve stress-induced alterations in ipsilateral lung become less considerable, whereas all spectra of changes in contralateral lung is remained.
Assuntos
Capsaicina/farmacologia , Neurônios Aferentes/metabolismo , Neuropeptídeos/metabolismo , Surfactantes Pulmonares/química , Estresse Psicológico/metabolismo , Nervo Vago/metabolismo , Animais , Pulmão/inervação , Lisofosfolipídeos/análise , Masculino , Neurônios Aferentes/química , Neurônios Aferentes/efeitos dos fármacos , Fosfatidilcolinas/análise , Surfactantes Pulmonares/metabolismo , Ratos , Propriedades de Superfície , Nervo Vago/química , Nervo Vago/efeitos dos fármacosRESUMO
In chronic experiments on rabbits and rats, parameters of eye homeostasis (intraocular pressure and ocular hydrodynamics) and lungs (water balance and surface-active properties of surfactant) were studied during electrical stimulation of the locus coeruleus against the background of chronic stress induced in rabbits by repeated electrical stimulation of the ventromedial nucleus and in rats by daily immobilization on a platform. Stimulation of the locus coeruleus eliminated ocular hypertension of hypothalamic origin and stress-induced disturbances in surface activity, blood volume, and water balance in the lungs.
Assuntos
Locus Cerúleo/fisiopatologia , Hipertensão Ocular/etiologia , Surfactantes Pulmonares/metabolismo , Estresse Psicológico/fisiopatologia , Animais , Estimulação Elétrica , Imobilização , Pulmão/fisiopatologia , Hipertensão Ocular/fisiopatologia , Coelhos , Ratos , Equilíbrio HidroeletrolíticoRESUMO
In chronic experiments on non-line white rats the influence of system (intraperitoneal) and central (into the lateral brain ventricle) administration of substance P on lung surfactant system was studied in stressed and non-stressed animals. A single injection of substance P limited pulmonary surfactant activity disorders in immobilisation stress. Stress-induced increase of phospholipids level in broncho-alveolar lavage fluid remained the same in intracerebroventricular administration and was partly reduced in intraperitoneal one. In intact rats, a single injection of peptide was accompanied by alveolar phospholipids accumulation. In rabbits, multiple intracerebroventricular injections of substance P enhanced the opposite effect.