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1222. Nesfatin-1 influences the excitability of gastric distension-responsive neurons in the ventromedial hypothalamic nucleus of rats
- Creator:
- Feng, H., Wang, Q., Guo, F., Han, X., Pang, M., Sun, X., Gong, Y., and Xu, L.
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, Nesfatin-1, ventromedial hypothalamic nucleus, hippocampus, gastric distension responsive neurons, 14, and 612
- Language:
- English
- Description:
- The present study investigated the effects of nesfatin-1 on gastric distension (GD)-responsive neurons via an interaction with corticotropin-releasing factor (CRF) receptor signaling in the ventromedial hypothalamic nucleus (VMH), and the potential regulation of these effects by hippocampal projections to VMH. Extracellular single-unit discharges were recorded in VHM following administration of nesfatin-1. The projection of nerve fibers and expression of nesfatin-1 were assessed by retrograde tracing and fluoro-immunohistochemical staining, respectively. Results showed that there were GD-responsive neurons in VMH; Nesfatin-1 administration and electrical stimulation of hippocampal CA1 sub-region altered the firing rate of these neurons. These changes could be partially blocked by pretreatment with the non-selective CRF antagonist astressin-B or an antibody to NUCB2/nesfatin-1. Electrolytic lesion of CA1 hippocampus reduced the effects of nesfatin-1 on VMH GD-responsive neuronal activity. These studies suggest that nesfatin-1 plays an important role in GD-responsive neuronal activity through interactions with CRF signaling pathways in VMH. The hippocampus may participate in the modulation of nesfatin-1-mediated effects in VMH., H. Feng, Q. Wang, F. Guo, X. Han, M. Pang, X. Sun, Y. Gong, L. Xu., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1223. Neuregulin-1 protects against doxorubicin-induced apoptosis in cardiomyocytes through an akt-dependent pathway
- Creator:
- An, T., Zhang, Y., Huang, Y., Zhang, R., Yin, S., Guo, X., Wang, Y., Zou, C., Wei, B., Lv, R., Zhou, Q., and Zhang, J.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, neuregulin, doxorubicin, apoptosis, cardiomyocyte, akt, 14, and 612
- Language:
- English
- Description:
- In previous studies, it has been shown that recombinant human neuregulin-1(rhNRG-1) is capable of improving the survival rate in animal models of doxorubicin (DOX)-induced cardiomyopathy; however, the underlying mechanism of this phenomenon remains unknown. In this study, the role of rhNRG-1 in attenuating doxorubicin-induce apoptosis is confirmed. Neonatal rat ventricular myocytes (NRVMs) were subjected to various treatments, in order to both induce apoptosis and determine the effects of rhNRG-1 on the process. Activation of apoptosis was determined by observing increases in the protein levels of classic apoptosis markers (including cleaved caspase-3, cytochrome c, Bcl-2, BAX and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining). The activation of Akt was detected by means of western blot analysis. The study results showed that doxorubicin increased the number of TUNEL positive cells, as well as the protein levels of cleaved caspase-3 and cytochrome c, and reduced the ratio of Bcl-2/Bax. However, all of these effects were markedly antagonized by pretreament with rhNRG-1. It was then further demonstrated that the effects of rhNRG-1 could be blocked by the phosphoinositole-3-kinase inhibitor LY294002, indicating the involvement of the Akt process in mediating the process. RhNRG-1 is a potent inhibitor of doxorubicin-induced apoptosis, which acts through the PI3K-Akt pathway. RhNRG-1 is a novel therapeutic drug which may be effective in preventing further damage from occurring in DOX-induced damaged myocardium., T. An, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1224. Neurobiological aspects of depressive disorder and antidepressant treatment: role of glia
- Creator:
- Marek Páv, Hana Kovářů, Anežka Fišerová, Eva Havrdová, and Věra Lisá
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, psychiatrie, biochemie, deprese, nálada, antidepresiva, stres (psychologie), gliomy, imunitní systém, signální transdukce, psychiatry, biochemistry, depression, mood (psychology), antidepressants, stress (psychology), gliomas, immune system, signal transduction, hippocampus, neurogenesis, astrocyte, natural killer cells, guanine-binding proteins, G proteins, 14, and 612
- Language:
- English
- Description:
- Depression is a complex disorder related to chronic inflammatory processes, chronic stress changes and a hippocampal response. There is a increasing knowledge about the role of glial cells in nutrient supply to neurons, maintenance of synaptic contacts and tissue homeostasis within the CNS. Glial cells, viewed in the past as passive elements with a limited influence on neuronal function, are becoming recognized as active partners of neurons and are starting to be discussed as a possible therapeutic target. Their role in the pathogenesis of depressive disorders is also being reconsidered. Attention is devoted to studies of the different types of antidepressants and their effects on transmembrane signaling, including levels of α subunits of G proteins in C6 glioma cells in vitro as a model of postsynaptic changes in vivo. These models indicate similarities in antidepressant effects on G proteins of brain cells and effector cells of natural immunity, natural killers and granulocytes. Thus, an antidepressant response can exhibit certain common characteristics in functionally different systems which also participate in disease pathogenesis. There are, however, differences in the astrocyte G-protein responses to antidepressant treatment, indicating that antidepressants differ in their effect on glial signalization. Today mainstream approach to neurobiological basis of depressive disorders and other mood illnesses is linked to abnormalities in transmembrane signal transduction via G-protein coupled receptors. Intracellular signalization cascade modulation results in the activation of transcription factors with subsequent increased production of a wide array of products including growth factors and to changes in cellular activity and reactivity., M. Páv, H. Kovářů, A. Fišerová, E. Havrdová, V. Lisá., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1225. Neurogenic pulmonary edema induced by spinal cord injury in spontaneously hypertensive and dahl salt hypertensive rats
- Creator:
- Šedý, J., Jaroslav Kuneš, and Jiří Zicha
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypertenze, hypertension, rat, neurogenic pulmonary edema, SHR, dahl rats, 14, and 612
- Language:
- English
- Description:
- Neurogenic pulmonary edema (NPE), which is induced by acute spinal cord compression (SCC) unde r the mild (1.5 %) isoflurane anesthesia, is highly dependent on baroreflex-mediated bradycardia because a deeper (3 %) isoflurane anesthesia or atropine pretreatment comple tely abolished bradycardia occurrence and NPE development in rats subjected to SCC. The aim of the present study was to evaluate whether hypertension- associated impairment of baroreflex sensitivity might exert some protection against NPE developmen t in hypertensive animals. We therefore studied SCC-induced NPE development in two forms of experimental hypertension - spontaneously hypertensive rats (SHR) and salt hypertensive Dahl rats, which were reported to have reduced baroreflex sensitivity. SCC elicited NPE in both hypertensive models irrespective of their baroreflex sensitivity. It is evident that a moderate impairment of baroreflex sensitivity, which was demonstrated in salt hypertensive Dahl rats, does not exert sufficient protective effects against NPE development., J. Šedý, J. Kuneš, J. Zicha., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1226. Neurohumoral control of gastrointestinal motility
- Creator:
- Hansen, M. B.
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hormony, recenze, hormones, reviews, 5-Hydroxytryptamine, gastrointestinal, enteric nervous system, interstitial cells of cajal, motility, serotonin, 14, and 612
- Language:
- English
- Description:
- Neurohumoral substances and their receptors play a major part in the complex regulation of gastrointestinal motility and have therefore been the predominant targets for drug development. The numerous receptors involved in motility are located mainly on smooth muscle cells and neuronal structures in the extrinsic and intrinsic parts of the enteric nervous system. Within this system, receptor agonists and antagonists interacts directly to modify excitatory or inhibitory signals. In view of this complexity it is not surprising that our knowledge about the mechanisms of actions of the various neurohormones and drugs affecting gut motility has been rather fragmented and incomplete. However, recently substantial progress has been achieved, and drug therapy for gut dysmotility is emerging, based primarily on neurohumoral receptors. This paper presents a selective review of the neurohumoral regulatory mechanisms of gastrointestinal motility. In this context, the physiology and pharmacology of the smooth muscle cells, gastrointestinal motility and dysmotility, the enteric nervous system, gastrointestinal reflexes, and serotonin is presented. Further investigation and understanding of the transmitters and receptors involved in especially the reflex activation of peristalsis is crucial for the development of novel therapies for motility disorders., M. B. Hansen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1227. Neuromedin beta: P73T polymorphism in overweight and obese subjects
- Creator:
- Spálová, Jana., Hana Zamrazilová, Josef Včelák, Markéta Vaňková, Petra Lukášová, Martin Hill, Karolína Hlavatá, Petra Šrámková, Martin Fried, Bashar Aldhoon, Marie Kunešová, Běla Bendlová, and Vojtěch Hainer
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, endokrinologie, obezita, redukce tělesné hmotnosti, endocrinology, obesity, weight loss, neuromedin beta, gene polymorphism, eating behaviour, nutrient intake, 14, and 612
- Language:
- English
- Description:
- Neuromedin beta (NMB) is a member of the bombesin-like peptide family expressed in brain, gastroin testinal tract, pancreas, adrenals and adipose tissue. The aim of our study was to compare the frequency of P73T polymorphism in overweight and obese patients (37 men: age 50.6±11.7 years, BMI 41.1±7.8 kg/m2; 255 women: age 49.0±11.9 years, BMI 37.9±6.8 kg/m2) with that of healthy normal weight subjects (51 men: age 28.2±7.1 years, BMI 22.3±2.0 kg/m2; 104 women: age 29.1±9.1 years, BMI 21.5±1.9 kg/m2) and to investigate the polymorphism’s influence on anthropometric, nutritional and psychobehavioral parameters in overweight/obese patients both at the baseline examination and at a control visit carried out 2.5 years later, regardless of the patient́s compliance with the weight reduction program. No significant differences in the genotype distribution were demonstrated between normal weight and overweight/obese subjects. Male T allele non-carriers compared to T allele carriers had higher energy (p=0.009), protein (p=0.018) and fat (p=0.002) intakes and hunger score (p=0.015) at the beginning of treatment. Male T allele non-carriers had a more favorable response to weight management at the follow-up, as they exhibited a significant reduction in waist circumference, energy intake and depression score as well as a significant increase in dietary restraint. No significant differences between carriers and non-carriers were demonstrated in women at the baseline examination. Both female T allele carriers and non-carriers demonstrated similar significant changes in nutritional parameters and in restraint score at the follow-up. Nevertheless, only female non-carriers showed a significant decrease in the hunger score., J. Spálová, H. Zamrazilová, J. Včelák, M. Vaňková, P. Lukášová, M. Hill, K. Hlavatá, P. Šrámková, M. Fried, B. Aldhoon, M. Kunešová, B. Bendlová, V. Hainer., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1228. Neuronal circuits involved in osmotic challenges
- Creator:
- Dos Santos Moreira, M. C., Naves, L. M., Marques, S. M., Silva, E. F., Rebelo, A. C. S., Colombari, E., and Pedrino, G. R.
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- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, body fluid homeostasis, osmosensory areas, cute hyperosmotic challenge, chronic hyperosmotic challenge, 14, and 612
- Language:
- English
- Description:
- The maintenance of plasma sodium concentration within a narrow limit is crucial to life. When it differs from normal physiological patterns, several mechanisms are activated in order to restore body fluid homeostasis. Such mechanisms may be vegetative and/or behavioral, and several regions of the central nervous system (CNS) are involved in their triggering. Some of these are responsible for sensory pathways that per ceive a disturbance of the body fluid homeostasis and transmit information to other regions. These regions, in turn, initiate adequate adjustments in order to restore homeostasis. The main cardiovascular and autonomic responses to a change in plasma sodium concentration are: i) changes in arterial blood pressure and heart rate; ii) changes in sympathetic activity to the renal system in order to ensure adequate renal sodium excretion/absorption, and iii) the secretion of compounds involved in sodium ion home ostasis (ANP, Ang-II, and ADH, for example). Due to their cardiovascular effects, hypertonic saline solutions have been used to promote resuscitation in hemorrhagic patients, thereby increasing survival rates following trauma. In the present review, we exp ose and discuss the role of several CNS regions involved in body fluid homeostasis and the effects of acute and chronic hyperosmotic challenges., M. C. Dos Santos Moreira, L. M. Naves, S. M. Marques, E. F. Silva, A. C. S. Rebelo, E. Colombari, G. R. Pedrino., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1229. Neurophysiological and behavioral responses to olfactory stimuli in the snail Helix pomatia L
- Creator:
- Voss, M.
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- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hlemýžď zahradní, pachy, šneci, Helix pomatia, odors, chemosensitivity, olfaction, snail, 14, and 612
- Language:
- English
- Description:
- Some aspects of olfactory sensitivity in the pulmonate Helix pomatia L. were studied by means of neurophysiological and behavioral methods. Single fiber recordings were carried out in the olfactory nerve of the posterior tentacles. Olfactory stimulations with different odors were performed by means of a continuous air stream. The order of neuronal sensitivity to different odors was as follows: ethanol³ ethyl acetate > pentanol > hexanol > octanol > diethyl malonate > vanillin. Furthermore, the results revealed a relative specificity for some substances. A comparison between neurophysiological and behavioral data shows that those substances, which cause the highest increases in impulse frequency, also evoke a behavioral avoidance reaction., M. Voss., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1230. Neurosteroid modulation of ionotropic glutamate receptors and excitatory synaptic transmission
- Creator:
- Miloslav Sedláček, Miloslav Kořínek, Miloš Petrovič, Cais, O., Adamusová, E., Hana Chodounská, and Ladislav Vyklický
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- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, neurologie, physiology, neurology, N-methyl-D-aspartate receptor, AMPA receptor, glutamate receptor, EPSC, neurosteroid, allosteric modulation, 14, and 612
- Language:
- English
- Description:
- Ionotropic glutamate receptors function can be affected by neurosteroids, both positively and negatively. N-methyl-D-aspartate (NMDA) receptor responses to exogenously applied glutamate are potentiated or inhibited (depending on the receptor subunit composition) by pregnenolone sulphate (PS) and inhibited by pregnenolone sulphate (3α5βS). While PS effect is most pronounced when its application precedes that of glutamate, 3α5βS only binds to receptors already activated. Synaptically activated NMDA receptors are inhibited by 3α5βS, though to a lesser extent than those tonically activated by exogenous glutamate. PS, on the other hand, shows virtually no effect on any of the models of synaptically activated NMDA receptors. The site of neurosteroid action at the receptor molecule has not yet been identified, however, the experiments indicate that there are at least two distinct extracellularly located binding sites for PS mediating its potentiating and inhibitory effects respectively. Experiments with chimeric receptors revealed the importance of the extracellular loop connecting the third and the fourth transmembrane domain of the receptor NR2 subunit for the neurosteroid action, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/kainate receptors are inhibited by both PS and 3α5βS. These neurosteroids also affect AMPA receptors-mediated synaptic transmission, however, in a rather indirect way, through presynaptically located targets of action., M. Sedláček, M. Kořínek, M. Petrovič, O. Cais, E. Adamusová, H. Chodounská, L. Vyklický Jr., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public