Goldfish undergo an adaptive morphological change in their gills involving the reversible growth and loss of a mass of cells (interlamellar cell mass, ILCM) in between the lamellae depending on oxygen demand, which can be altered by the environment or metabolic demands of the individual. The ILCM contributes to decreased passive Na+ efflux across the gill. Active uptake is maintained by the re-distribution of the ionocytes expressing Na+-uptake relevant genes (NHEs and H+-ATPase) to the outer edge of the ILCM where they can establish contact with the external environment and/or lamellar epithelium. This adaptation is thought to be partly responsible for the extreme anoxia tolerance demonstrated by goldfish, which they experience on a seasonal basis living in a pond environment. Hypoxia and hypercapnia are frequently encountered in such freshwater environments and as such, the effect of the ILCM on the capacity for acid-base regulation was evaluated. Differences in the time course of acid excretion to the environment without effect on systemic pH regulation were likely the result of the ILCM.

Eine optimale Regulation der Koronardurchblutung ist für die Aufrechterhaltung der kardialen Pumpfunktion und damit der systemischen Perfusion von größter Bedeutung. Da Einschränkungen der Durchblutungszunahme des Herzmuskels Einschränkungen des maximalen myokardialen Sauerstoffverbrauchs und damit der Herzleistung zur Folge haben, ist es notwendig, die Koronardurchblutung kurzfristig an die jeweilige Stoffwechsellage des Herzens anzupassen (metabolische Koronarflussregulation). Die lokal-metabolischen Mechanismen gehören zu den wirksamsten Komponenten der Regulation der myokardialen Durchblutung und funktionieren auch am isolierten (denervierten) Herz. Dabei ist die hyperkapnie- und azidoseinduzierte Koronardilatation ein wesentlicher Bestandteil der metabolischen Koronarflussregulation. Die vorliegende Arbeit befasst sich mit der Hypothese der Abhängikeit der hyperkapnieinduzierten Koronardilatation von einer intakten NO-Produktion. Das Koronarsystem des isolierten WT-Mausherzens reagiert auf akute Hyperkapnie (91 % O2, 9 % CO2) mit einer deutlichen Koronarflusssteigerung von ca. 35 % über dem Basalfluss.Es konnte gezeigt werden das Stickstoffmonoxid (NO) und ATP-abhängige Kaliumkanäle (K+ATP-Kanäle) für die Koronarflussregulation der Maus eine ausschlagebende Rolle spielen und neben der Aufrechterhaltung des Basalflusses auch an der Vermittlung der hyperkapnieinduzierten Koronardilatation maßgeblich beteiligt sind.Interessanterweise ist bei einem Fehlen der endothelialen NO-Synthase durch genetischen Knockout die hyperkapnieinduzierte Flussantwort in Kinetik und Ausmaß vollständig erhalten. Die Vermittlung kann dabei durch andere Mechanismen kompensiert werden, wie zum Beispiel einer verstärkten Aktivität der K+ATP-Kanäle. Prostaglandine und neuronale NO-Synthase scheinen sowohl beim Wildtypherzen als auch bei Herzen mit fehlender NO-Synthase für die hyperkapnieinduzierte Koronardilatation von untergeordneter Bedeutung. Nach chronischer pharmakologischer Blockade der NO-Synthase durch zweiwöchige L-NAME Tränkung bleibt die hyperkapnieinduzierte Koronardilatation erhalten durch NOS-unabhängige Mechanismen. Die hyperkapnieinduzierte Flussantwort ist bei Herzen von weiblichen eNOSKO Tieren vorhanden, erscheint jedoch gegenüber den männlichen Mäusen geringer ausgeprägt. Daher wird vermutet, dass die Mediatorsysteme der endothelabhängigen Koronarflussregulation geschlechtsspezifisch bzw. geschlechtsabhängig sind.

Goldfish undergo an adaptive morphological change in their gills involving the reversible growth and loss of a mass of cells (interlamellar cell mass, ILCM) in between the lamellae depending on oxygen demand, which can be altered by the environment or metabolic demands of the individual. The ILCM contributes to decreased passive Na+ efflux across the gill. Active uptake is maintained by the re-distribution of the ionocytes expressing Na+-uptake relevant genes (NHEs and H+-ATPase) to the outer edge of the ILCM where they can establish contact with the external environment and/or lamellar epithelium. This adaptation is thought to be partly responsible for the extreme anoxia tolerance demonstrated by goldfish, which they experience on a seasonal basis living in a pond environment. Hypoxia and hypercapnia are frequently encountered in such freshwater environments and as such, the effect of the ILCM on the capacity for acid-base regulation was evaluated. Differences in the time course of acid excretion to the environment without effect on systemic pH regulation were likely the result of the ILCM.

Název: Hyperkapnie a difuse plynů ve sněhové lavině - (Změny funkčních parametrů jedinců v krizové situaci) Cíle práce: Cílem studie bylo kontinuální sledování kompenzačních mechanismů, zejména změn ventilačně-respiračních ukazatelů, v simulované sněhové lavině. Metoda: K získání dat byl použit experiment a nestandardizovaný dotazník. Výběr souboru byl vzhledem ke sledované problematice přísně selektivní. Výzkumu se účastnilo 22 probandů, ale po analýze dat bylo pro nesplnění požadovaných kritérií 11 osob vyřazeno. Soubor tedy tvořilo 11 zdravých mužů průměrného věku 25,3 let. Před vlastním experimentem byla pomocí osobního spirometru testována senzitivita na hyperkapnii a hypoxii (výdrž v apnoi) a dechová zdatnost (vitální kapacita plic s usilovným výdechem). Experimentální situaci představovalo jak dýchání do uzavřeného objemu (8 l), tak do vytvořené vzduchové kapsy ve sněhu (400 ml). Kontinuální záznamy oběhových funkcí (srdeční frekvence, krevní tlak) a ventilačně-respiračních parametrů (dechová frekvence, dechový objem, minutová ventilace, obsah O2 a CO2 ve vdechovaném a vydechovaném vzduchu, odpor při výdechu a saturace krve kyslíkem) byly snímány pacientským monitorem DATEX Ohmeda. Vzhledem k charakteru dat byla využita analýza rozptylu při opakovaném měření se dvěma faktory (dvoucestná...

Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-21T12:17:25Z No. of bitstreams: 1 DissMCV.pdf: 1396676 bytes, checksum: d3fa0ce7f0f0504dfe6926528b1e7366 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-21T18:23:20Z (GMT) No. of bitstreams: 1 DissMCV.pdf: 1396676 bytes, checksum: d3fa0ce7f0f0504dfe6926528b1e7366 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-21T18:23:27Z (GMT) No. of bitstreams: 1 DissMCV.pdf: 1396676 bytes, checksum: d3fa0ce7f0f0504dfe6926528b1e7366 (MD5) / Made available in DSpace on 2016-09-21T18:23:33Z (GMT). No. of bitstreams: 1 DissMCV.pdf: 1396676 bytes, checksum: d3fa0ce7f0f0504dfe6926528b1e7366 (MD5) Previous issue date: 2015-10-16 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The orexins are hypothalamic neuropeptides involved in an array of functions such as regulation of sleep/wake states and chemoreception to CO2/pH. The Locus coeruleus (LC) is a chemosensitive site and expresses an extensive population of orexin receptor 1 (OX1R). Here we tested the hypothesis that OX1Rs located in the LC participate in the ventilatory response to hypercapnia in a vigilance state and diurnal cycle-dependent manner. To this end, we performed unilateral injections of SB-334867 (OX1R antagonist, 5 mM) into the LC of male Wistar rats and evaluated the ventilatory response to 7% CO2 during wakefulness and sleep in the dark and light phase of the diurnal cycle. Hypercapnia induced an increase in ventilation in all groups compared to normocapnic values. However, the injection of (SB-334867) promoted an attenuation of the hypercapnic chemorreflex during wakefulness, due to changes in VT. In addition, microinjection of SB-334867 decreases the wakefulness time during dark phase. We suggest that projections of orexin-containing neurons to the LC contribute, via OX1Rs, to the hypercapnic chemoreflex during wakefulness in the dark phase. / As orexinas são neuropeptídeos hipotalâmicos envolvidos em uma variedade de funções, tais como, na regulação do ciclo sono-vigília e na quimiorecepção ao CO2 / pH. O locus coeruleus (LC) é um núcleo quimiossensível e expressa uma extensa população de receptor de orexina 1 (OX1R). Portanto, nós testamos a hipótese de que OX1Rs localizados no LC participam da resposta ventilatória à hipercapnia no estado de vigília de maneira dependente do ciclo claro e escuro. A participação da neurotransmissão orexinérgica do LC na resposta ventilatória à hipercapnia foi avaliada por meio da microinjeção do antagonista de receptor-1 OXR- 1 (SB-334867, 5 mM) no LC de ratos Wistar não anestesiados durante o sono e a vigília nas fases clara e escura. Nossos resultados demonstraram que a hipercapnia induz um aumento significativo da ventilação em todos os grupos comparado aos valores de ventilação na normocapnia. No entanto, na fase escura, a microinjeção do SB-334867 promoveu uma atenuação do quimiorreflexo hipercápnico durante a vigília, mas não durante o sono devido à diminuição do volume corrente VT. Adicionalmente, a microinjeção do SB-334867 diminui o tempo que os animais passam acordados em normocapnia na fase escura. Portanto, nossos dados sugerem que as projeções orexinérgicas para o LC atuando em OXR-1 exercem uma modulação excitatória na resposta ventilatória ao CO2 durante a vigília na fase escura. / 2014/00330-3

Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-23T12:35:49Z No. of bitstreams: 1 DissJMIM.pdf: 1160970 bytes, checksum: 5d770f3bd6013be1ec19d00de0a6da90 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T17:59:57Z (GMT) No. of bitstreams: 1 DissJMIM.pdf: 1160970 bytes, checksum: 5d770f3bd6013be1ec19d00de0a6da90 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:00:03Z (GMT) No. of bitstreams: 1 DissJMIM.pdf: 1160970 bytes, checksum: 5d770f3bd6013be1ec19d00de0a6da90 (MD5) / Made available in DSpace on 2016-10-04T18:00:10Z (GMT). No. of bitstreams: 1 DissJMIM.pdf: 1160970 bytes, checksum: 5d770f3bd6013be1ec19d00de0a6da90 (MD5) Previous issue date: 2015-09-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Locus coeruleus (LC) is a pontine noradrenergic group that acts as a central chemoreceptor to CO2/pH and it is involved in the cognitive aspects of stress response and it is associated with a large number of physiological and behavioral processes, including sleepwake cycle, feeding, cardiovascular and respiratory control, nociception, thermoregulation and learning. The LC has also been implicated in the cognitive aspects of stress responses, in part through the action of corticotropin releasing factor (CRF), which when released in these situations increases the firing frequency of LC noradrenergic neurons. CRF is the largest stimulator of the pituitary secretion of ACTH (adrenocorticotropic hormone) and their receptors (types 1 and 2) are widely distributed in the central nervous system, including the LC. Thus, we tested the involvement of CRF1 receptors (CRF1) located in the LC in the ventilatory and thermal responses induced by hypercapnia (7%CO2) in rats. To this end, we injected antalarmin (a CRF1 antagonist, 0.05 and 0,1 μg/0.1 μL) into the LC of male Wistar rats. Pulmonary ventilation (VE) and body temperature (Tb, dataloggers) were measured in air and followed by 7% CO2 in unanesthetized rats. There were no differences in body temperature between groups under normocapnia and hypercapnia. We observed an increased ventilation in normocapnia, at 5 to 15 minutes after microinjection of antalarmin (dose 0.1 μg / 0.1 μL) compared to the control, due to an increase in tidal volume. The hypercapnic response in antalarmine treated animals was higher compared to control groups. The dose of 0.05 μg / 0.1 μL caused an increase in ventilation 15 min after CO2 exposure and this response increased further with the dose of 0.1 μg / 0.1 μL at 30 minutes after hypercapnia, due to an increased tidal volume. Our results suggest that CRF1 receptors in the LC exert a tonic inhibitory role in the ventilation and the inhibitory modulation of the respiratory response to CO2. / O locus coeruleus (LC) é um grupamento noradrenérgico pontino que atua como um quimiorreceptor central a CO2/pH e está associado a um grande número de processos fisiológicos e comportamentais, entre eles, ciclo sono-vigília, alimentação, controle respiratório e cardiovascular, nocicepção, termorregulação e aprendizado. O LC tem sido também implicado nos aspectos cognitivos na resposta ao stress, em parte por meio da ação do fator liberador de corticotrofina (CRF) que, ao ser liberado nessas situações, aumenta a frequência de disparo dos neurônios noradrenérgicos do LC. O CRF é o maior estimulador da secreção hipofisária de ACTH (hormônio adrenocorticotrófico), sendo que seus receptores (tipos 1 e 2) estão difusamente distribuídos no sistema nervoso central (SNC), incluindo o LC. Neste contexto, nós testamos o envolvimento dos receptores CRF1 no LC na resposta respiratória ao CO2 em ratos adultos não anestesiados, por meio da microinjeção de antalarmina (antagonista de CRF1) no LC (0,05 e 0,1 μg / 0,1 μL). A ventilação pulmonar (VE) e a temperatura corporal (Tc, dataloggers) foram medidas no ar e seguido de 7% CO2 em ratos não anestesiados. Não houve alteração na Tc entre os grupos em normocapnia e hipercapnia. Observamos aumento da ventilação em normocapnia, nos tempos de 5 a 15 minutos após a microinjeção de antalarmina (dose 0,1 μg / 0,1 μL) em comparação ao controle, devido a um aumento do volume corrente. A resposta hipercápnica de animais tratados com o antagonista de CRF1 foi maior em ambas as doses administradas, a dose de 0,05 μg / 0,1 μL provocou um aumento da ventilação em 15 min após a exposição CO2, e essa resposta aumentou ainda mais na dose de 0,1 μg / 0,1 μL em 30 minutos após a exposição CO2 em comparação com animais tratados com veículos, devido a um aumento do volume corrente. Nossos resultados sugerem que os receptores CRF1 no LC exercem um papel inibitório tônico na ventilação e a modulação inibitória na resposta respiratória ao CO2.

 Keywords: Lung Tx, EVLP, NHBD, IR injury, ROS, hypercapnia, gender differences This dissertation thesis deals with a very topical issue of the lack of donor organs for lung transplants. As with other organs, the number of patients on waiting lists in terminal stages of their diseases is also constantly rising but there is not an adequate increase in donor organs. We focused our experimental work on the development of research concerning the solution which is most successful in a long-term perspective, i.e. organ transplants from non- heart-beating donors (NHBDs), in an ex vivo lung transplant protocol (EVLP) on an animal model (Wistar rats). This is a method which is clinically established worldwide (in the Czech Republic only experimentally) and is constantly subject to further research. Based on earlier studies, we focused the first experimental part of this work on the potential protective effect of hypercapnic ventilation on ischemia-reperfusion (IR) lung injury in EVLP. The study proved that the hypercapnic ventilation has a protective effect on the generation of reactive oxygen species (ROS) in IR lung injury, but only when used in the period of reperfusion. In the second experimental study, we followed up a very topical issue of the effect of gender on IR lung injury in EVLP in...

Goldfish undergo an adaptive morphological change in their gills involving the reversible growth and loss of a mass of cells (interlamellar cell mass, ILCM) in between the lamellae depending on oxygen demand, which can be altered by the environment or metabolic demands of the individual. The ILCM contributes to decreased passive Na+ efflux across the gill. Active uptake is maintained by the re-distribution of the ionocytes expressing Na+-uptake relevant genes (NHEs and H+-ATPase) to the outer edge of the ILCM where they can establish contact with the external environment and/or lamellar epithelium. This adaptation is thought to be partly responsible for the extreme anoxia tolerance demonstrated by goldfish, which they experience on a seasonal basis living in a pond environment. Hypoxia and hypercapnia are frequently encountered in such freshwater environments and as such, the effect of the ILCM on the capacity for acid-base regulation was evaluated. Differences in the time course of acid excretion to the environment without effect on systemic pH regulation were likely the result of the ILCM.

No description available.

Title: Prolonged apnea: monitoring brain activity in freedivers Objectives: The aim of this study is to monitor the brain electrical activity during the prolonged apnea in freedivers. Prolonged apnea in the water and prolonged dry apnea were compared to each other and also to a resting state before the apnea, all states with the eyes closed. Brain activity was obtained from the scalp EEG and evaluated using the sLORETA program. Methods: The research was conducted in 11 healthy men at the age of 23 - 51. The data was obtained from the scalp EEG. The record was first taken at a resting state before the apneas with eyes closed, then at maximum prolonged dry apnea with eyes closed and finally at maximum prolonged apnea in the water with eyes closed. The lenghts of the prolonged apneas ranged from 2:15 minutes to 5:30 minutes in idividual probands. There were pauses of at least three minutes between each apnea as by the proband's needs. The compared pair groups were following: prolonged apnea in the water against prolonged dry apnea, prolonged apnea in the water against resting state before the apnea and finally prolonged dry apnea against resting state before the apnea, all with the eyes closed. Selected sections of EEG record without artefacts were processed by sLORETA program. In the statistical...