Results 131 to 140 of about 38,036 (248)

Brain strain: Blood flow and metabolism in environmental extremes

Experimental Physiology, EarlyView.
Abstract This narrative review compares and contrasts the most commonly encountered environmental stressors on human cerebrovascular functioning. From high altitude and space, extreme apnoea, heat and cold stress, the impact of these stressors on the regulation of cerebral blood flow (CBF) and oxygen metabolism (CMRO2${\mathrm{CM}}{{\mathrm{R}}_ ...
Dario Vrdoljak, Damian M. Bailey, Travis D. Gibbons, Philip N. Ainslie   +3 more
wiley   +1 more source

The effect of hypercapnia on static cerebral autoregulation

, 2014
Hypercapnia impairs cerebrovascular control during rapid changes in blood pressure (BP); however, data concerning the effect of hypercapnia on steady state, nonpharmacological increases in BP is scarce. We recruited fifteen healthy volunteers (mean ± SD:
Thomas, Kate N, Perry, Blake G, Mündel, Toby, Lucas, Samuel J E; id_orcid, Cochrane, Darryl J   +4 more
core   +1 more source

Cerebral and peripheral haemodynamics at rest and in response to orthostasis during 3 days of simulated heatwave

Experimental Physiology, EarlyView.
Abstract Acute heat stress reduces cerebral haemodynamics and orthostatic tolerance. However, the haemodynamic response to orthostasis during prolonged heat stress typical of heatwaves is unknown. We hypothesised that thermoregulatory‐induced elevations in peripheral haemodynamics during 3 days of simulated heatwave would exacerbate orthostatic‐induced
Alexander T. Friend, Samuel J. Oliver, Lydia L. Simpson, Carmen Possnig, Gabriella M. K. Rossetti, Jason T. Fisher, Lydia Tsoutsoubi, Konstantinos Mantzios, Urša Ciuha, Leonidas G. Ioannou, Igor B. Mekjavic, Justin S. Lawley   +11 more
wiley   +1 more source

Splenic contraction associated with sudden, transient hypotension and sympathoexcitation in humans

Experimental Physiology, EarlyView.
Abstract The spleen is traditionally recognised for its roles in immunity and blood filtration, and it is known to contract and release stored erythrocytes in hypoxic conditions. Recent findings suggest that the spleen may also contribute to cardiovascular regulation.
Angelica Lodin‐Sundström, Gabriel Axelsson, Lisa Ljungberg, Mats H. Linér, Bodil Sjögreen, Johan P. A. Andersson   +5 more
wiley   +1 more source

ATP and mechanisms of central CO2 chemosensitivity [PDF]

ATP release from the surface of the ventro-lateral medulla (VLM) is integral to the hypercapnic response in vivo and can be seen in vitro. By employing horizontal slices of the ventral medulla containing the ventral chemosensitive nuclei, I have ...
Huckstepp, Robert T. R.
core  

Cerebral and peripheral vascular responses to hypercapnia

, 2022
During hypercapnia (elevated partial pressure of arterial CO₂; PaCO₂) cerebral blood flow (CBF) is elevated in order to maintain pH in the cerebral tissues; mean arterial pressure (MAP), minute ventilation (Vᴇ), and heart rate also increase. The shearing
Carr, Jordan Mark John Ramone
core  

Physiological and autonomic responses to intermittent low‐lung‐volume apnoea and pain sensitivity: A randomized controlled pilot trial

Experimental Physiology, EarlyView.
Abstract Intermittent apnoeas may induce hypoalgesia; however, the effects of low‐lung‐volume static apnoea have not been investigated. Eighty healthy participants were randomized to an apnoea group (AG) or a control group (CG). The AG performed a 6‐min protocol of intermittent static apnoea at low lung volume (passive exhalation), whereas the CG ...
Cristian Mendoza‐Arranz, Francisco De Asís‐Fernández, Guillermo Miravet‐Mingo, José Vicente León‐Hernández, José Fierro‐Marrero, Álvaro Reina‐Varona   +5 more
wiley   +1 more source

Mechanisms regulating cerebral perfusion during running exercise: Influence of foot strike‐induced pulsatility oscillations, CO2 reactivity and BP

The Journal of Physiology, EarlyView.
Abstract figure legend Young, healthy males and females completed an incremental running test, demonstrating a progressive increase in middle cerebral artery blood velocity (MCAv) up to maximal exercise despite reductions in end‐tidal CO2. To investigate the underlying mechanism, foot‐strike timing was synchronized to the diastolic phase of the cardiac
Lydia L. Simpson, Dean R. Perkins, Connor A. Howe, Christina D. Bruce, William K. Cornwell III, Justin S. Lawley   +5 more
wiley   +1 more source

The role of acid‐base balance in cerebrovascular and ventilatory responses to CO2 during 10 h normobaric hypoxia

The Journal of Physiology, EarlyView.
Abstract figure legend During 10 h exposures to normobaric hypoxia exposure there was a selective leftward shift in ventilatory response to hyperoxic hypercapnic rebreathing, but not the cerebrovascular response. The key findings are that the resetting of the central chemoreflex to lower PCO2${P_{{\mathrm{C}}{{\mathrm{O}}_2}}}$ during early hypoxic ...
Holly Barclay, Saptarshi Mukerji, Bengt Kayser, Jui‐Lin Fan   +3 more
wiley   +1 more source

Arterial–venous differences of brain‐derived neurotrophic factor isoforms across the brain and muscle after exercise at different intensities

The Journal of Physiology, EarlyView.
Abstract figure legend Exercise‐induced increases in forearm venous plasma and serum brain‐derived neurotrophic factor (BDNF) are often assumed to be indicative of release from the brain. Sixteen healthy and physically fit adults (20–40 years old) were recruited to investigate whether exercise‐induced changes in forearm venous mature BDNF (mBDNF) and ...
Olga Tarassova, Yiwen Jiang, Helena Wallin, Mats Jensen‐Urstad, Nikola Drca, Julia Röja, Marjan Pontén, Abram Katz, Jonna Nilsson, Maria M. Ekblom, Marcus Moberg   +10 more
wiley   +1 more source