Multispectral brain connectivity during visual attention distinguishes controlled from uncontrolled hypertension
J Physiol. 2024 Mar 22. doi: 10.1113/JP285568. Online ahead of print.ABSTRACTHypertension-related changes in brain function place individuals at higher risk for cognitive impairment and Alzheimer's disease. The existing functional neuroimaging literature has identified important neural and behavioural differences between normotensive and hypertensive individuals. However, previously-used methods (i.e. magnetic resonance imaging, functional near-infrared spectroscopy) rely on neurovascular coupling, which is a useful but indirect measure of neuronal activity. Furthermore, most studies fail to distinguish between controlled ...
Source: The Journal of Physiology - March 22, 2024 Category: Physiology Authors: Jake J Son Yasra Arif Davina Oludipe Lucas Weyrich Abraham D Killanin Alex I Wiesman Hannah J Okelberry Madelyn P Willett Hallie J Johnson Tony W Wilson Source Type: research
The neurorehabilitation of post-stroke dysphagia: Physiology and pathophysiology
J Physiol. 2024 Mar 22. doi: 10.1113/JP285564. Online ahead of print.ABSTRACTSwallowing is a complex process involving the precise contractions of numerous muscles of the head and neck, which act to process and shepherd ingested material from the oral cavity to its eventual destination, the stomach. Over the past five decades, information from animal and human studies has laid bare the complex network of neurones in the brainstem, cortex and cerebellum that are responsible for orchestrating each normal swallow. Amidst this complexity, problems can and often do occur that result in dysphagia, defined as impaired or disorder...
Source: The Journal of Physiology - March 22, 2024 Category: Physiology Authors: Ayodele Sasegbon Ivy Cheng Shaheen Hamdy Source Type: research
Multispectral brain connectivity during visual attention distinguishes controlled from uncontrolled hypertension
J Physiol. 2024 Mar 22. doi: 10.1113/JP285568. Online ahead of print.ABSTRACTHypertension-related changes in brain function place individuals at higher risk for cognitive impairment and Alzheimer's disease. The existing functional neuroimaging literature has identified important neural and behavioural differences between normotensive and hypertensive individuals. However, previously-used methods (i.e. magnetic resonance imaging, functional near-infrared spectroscopy) rely on neurovascular coupling, which is a useful but indirect measure of neuronal activity. Furthermore, most studies fail to distinguish between controlled ...
Source: The Journal of Physiology - March 22, 2024 Category: Physiology Authors: Jake J Son Yasra Arif Davina Oludipe Lucas Weyrich Abraham D Killanin Alex I Wiesman Hannah J Okelberry Madelyn P Willett Hallie J Johnson Tony W Wilson Source Type: research
The neurorehabilitation of post-stroke dysphagia: Physiology and pathophysiology
J Physiol. 2024 Mar 22. doi: 10.1113/JP285564. Online ahead of print.ABSTRACTSwallowing is a complex process involving the precise contractions of numerous muscles of the head and neck, which act to process and shepherd ingested material from the oral cavity to its eventual destination, the stomach. Over the past five decades, information from animal and human studies has laid bare the complex network of neurones in the brainstem, cortex and cerebellum that are responsible for orchestrating each normal swallow. Amidst this complexity, problems can and often do occur that result in dysphagia, defined as impaired or disorder...
Source: The Journal of Physiology - March 22, 2024 Category: Physiology Authors: Ayodele Sasegbon Ivy Cheng Shaheen Hamdy Source Type: research
The vascular geometry of the choriocapillaris is associated with spatially heterogeneous molecular exchange with the outer retina
J Physiol. 2024 Mar 21. doi: 10.1113/JP285050. Online ahead of print.ABSTRACTVision relies on the continuous exchange of material between the photoreceptors, retinal pigment epithelium and choriocapillaris, a dense microvascular bed located underneath the outer retina. The anatomy and physiology of the choriocapillaris and their association with retinal homeostasis have proven difficult to characterize, mainly because of the unusual geometry of this vascular bed. By analysing tissue dissected from 81 human eyes, we show that the thickness of the choriocapillaris does not vary significantly over large portions of the macula...
Source: The Journal of Physiology - March 21, 2024 Category: Physiology Authors: Caitlin D Faust Christian A Klettner Marc Toso Gregory S Hageman Ian Eames Philip J Luthert Moussa A Zouache Source Type: research
Motor unit modes in the calf muscles during a submaximal isometric contraction are changed by brief stretches
J Physiol. 2024 Mar 21. doi: 10.1113/JP285437. Online ahead of print.ABSTRACTThe purpose of our study was to investigate the influence of a stretch intervention on the common modulation of discharge rate among motor units in the calf muscles during a submaximal isometric contraction. The current report comprises a computational analysis of a motor unit dataset that we published previously (Mazzo et al., 2021). Motor unit activity was recorded from the three main plantar flexor muscles while participants performed an isometric contraction at 10% of the maximal voluntary contraction force before and after each of two interve...
Source: The Journal of Physiology - March 21, 2024 Category: Physiology Authors: Logan E Weinman Alessandro Del Vecchio Melissa R Mazzo Roger M Enoka Source Type: research
Monocarboxylate transporter 4 deficiency enhances high-intensity interval training-induced metabolic adaptations in skeletal muscle
In this study, our objective was to elucidate the effects of increased intramuscular lactate accumulation on skeletal muscle adaptation to training. To achieve this, we developed MCT4 knockout mice and confirmed that a lack of MCT4 indeed results in pronounced lactate accumulation in skeletal muscle during high-intensity exercise. A key finding was the significant enhancement in endurance exercise capacity at high intensities when MCT4 deficiency was paired with high-intensity interval training (HIIT). Furthermore, metabolic adaptations supportive of this enhanced exercise capacity were evident with the combination of MCT4...
Source: The Journal of Physiology - March 21, 2024 Category: Physiology Authors: Yuki Tamura Eunbin Jee Karina Kouzaki Takaya Kotani Koichi Nakazato Source Type: research
Systemic histone deacetylase inhibition ameliorates the aberrant responses to acute stress in socially isolated male mice
J Physiol. 2024 Mar 18. doi: 10.1113/JP285875. Online ahead of print.ABSTRACTAdverse experiences in early life can induce maladaptive responses to acute stress in later life. Chronic social isolation during adolescence is an early life adversity that can precipitate stress-related psychiatric disorders. We found that male mice after 8 weeks of adolescent social isolation (SI) have markedly increased aggression after being exposed to 2 h of restraint stress (RS), which was accompanied by a significant increase of AMPA receptor- and NMDA receptor-mediated synaptic transmission in prefrontal cortex (PFC) pyramidal neurons of ...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Luis Gustavo Hernandez Carballo Pei Li Rachel Senek Zhen Yan Source Type: research
Differential utilisation of subcellular skeletal muscle glycogen pools: a comparative analysis between 1 and 15 min of maximal exercise
In conclusion, distinct subcellular glycogen pools were differentially utilised during 1-min and 15-min maximal cycling exercise. Additionally, lowered carbohydrate and energy consumption after glycogen-depleting exercise altered glycogen storage by reducing particle size and numerical density, depending on subcellular localisation. KEY POINTS: In human skeletal muscle, glycogen particles are localised in distinct subcellular compartments, referred to as intermyofibrillar, intramyofibrillar and subsarcolemmal pools. The intermyofibrillar and subsarcolemmal pools are close to mitochondria, while the intramyofibrillar pool i...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Camilla Tvede Schytz Niels Ørtenblad Kasper Degn Gejl Joachim Nielsen Source Type: research
Antagonism of 5-HT < sub > 2 < /sub > receptors attenuates self-sustained firing of human motor units
J Physiol. 2024 Mar 19. doi: 10.1113/JP285867. Online ahead of print.ABSTRACT5-HT2 receptors on motoneurones play a critical role in facilitating persistent inward currents (PICs). Although facilitation of PICs can enhance self-sustained firing after periods of excitation, the relationship between 5-HT2 receptor activity and self-sustained firing in human motor units (MUs) has not been resolved. MU activity was assessed from the tibialis anterior of 10 healthy adults (24.9 ± 2.8 years) during two contraction protocols. Both protocols featured steady-state isometric contractions with constant descending drive to the motone...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Benjamin I Goodlich Gregory E P Pearcey Alessandro Del Vecchio Sean A Horan Justin J Kavanagh Source Type: research
Systemic histone deacetylase inhibition ameliorates the aberrant responses to acute stress in socially isolated male mice
J Physiol. 2024 Mar 18. doi: 10.1113/JP285875. Online ahead of print.ABSTRACTAdverse experiences in early life can induce maladaptive responses to acute stress in later life. Chronic social isolation during adolescence is an early life adversity that can precipitate stress-related psychiatric disorders. We found that male mice after 8 weeks of adolescent social isolation (SI) have markedly increased aggression after being exposed to 2 h of restraint stress (RS), which was accompanied by a significant increase of AMPA receptor- and NMDA receptor-mediated synaptic transmission in prefrontal cortex (PFC) pyramidal neurons of ...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Luis Gustavo Hernandez Carballo Pei Li Rachel Senek Zhen Yan Source Type: research
Differential utilisation of subcellular skeletal muscle glycogen pools: a comparative analysis between 1 and 15 min of maximal exercise
In conclusion, distinct subcellular glycogen pools were differentially utilised during 1-min and 15-min maximal cycling exercise. Additionally, lowered carbohydrate and energy consumption after glycogen-depleting exercise altered glycogen storage by reducing particle size and numerical density, depending on subcellular localisation. KEY POINTS: In human skeletal muscle, glycogen particles are localised in distinct subcellular compartments, referred to as intermyofibrillar, intramyofibrillar and subsarcolemmal pools. The intermyofibrillar and subsarcolemmal pools are close to mitochondria, while the intramyofibrillar pool i...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Camilla Tvede Schytz Niels Ørtenblad Kasper Degn Gejl Joachim Nielsen Source Type: research
Antagonism of 5-HT < sub > 2 < /sub > receptors attenuates self-sustained firing of human motor units
J Physiol. 2024 Mar 19. doi: 10.1113/JP285867. Online ahead of print.ABSTRACT5-HT2 receptors on motoneurones play a critical role in facilitating persistent inward currents (PICs). Although facilitation of PICs can enhance self-sustained firing after periods of excitation, the relationship between 5-HT2 receptor activity and self-sustained firing in human motor units (MUs) has not been resolved. MU activity was assessed from the tibialis anterior of 10 healthy adults (24.9 ± 2.8 years) during two contraction protocols. Both protocols featured steady-state isometric contractions with constant descending drive to the motone...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Benjamin I Goodlich Gregory E P Pearcey Alessandro Del Vecchio Sean A Horan Justin J Kavanagh Source Type: research
Systemic histone deacetylase inhibition ameliorates the aberrant responses to acute stress in socially isolated male mice
J Physiol. 2024 Mar 18. doi: 10.1113/JP285875. Online ahead of print.ABSTRACTAdverse experiences in early life can induce maladaptive responses to acute stress in later life. Chronic social isolation during adolescence is an early life adversity that can precipitate stress-related psychiatric disorders. We found that male mice after 8 weeks of adolescent social isolation (SI) have markedly increased aggression after being exposed to 2 h of restraint stress (RS), which was accompanied by a significant increase of AMPA receptor- and NMDA receptor-mediated synaptic transmission in prefrontal cortex (PFC) pyramidal neurons of ...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Luis Gustavo Hernandez Carballo Pei Li Rachel Senek Zhen Yan Source Type: research
Differential utilisation of subcellular skeletal muscle glycogen pools: a comparative analysis between 1 and 15 min of maximal exercise
In conclusion, distinct subcellular glycogen pools were differentially utilised during 1-min and 15-min maximal cycling exercise. Additionally, lowered carbohydrate and energy consumption after glycogen-depleting exercise altered glycogen storage by reducing particle size and numerical density, depending on subcellular localisation. KEY POINTS: In human skeletal muscle, glycogen particles are localised in distinct subcellular compartments, referred to as intermyofibrillar, intramyofibrillar and subsarcolemmal pools. The intermyofibrillar and subsarcolemmal pools are close to mitochondria, while the intramyofibrillar pool i...
Source: The Journal of Physiology - March 19, 2024 Category: Physiology Authors: Camilla Tvede Schytz Niels Ørtenblad Kasper Degn Gejl Joachim Nielsen Source Type: research
