The Journal of Physiology

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Propionate, a gut microbiota-derived short-chain fatty acid, influences fetal development and postnatal metabolic programming. Although the fetus lacks microbiota and endogenous propionate production, human pregnancies show a fetal-to-maternal propionate concentration ratio greater than unity, suggesting concentrative transport across the placenta. However, its underlying mechanism remains undefi…

Exercise at altitude is performed by a spectrum of individuals ranging from healthy to those with cardiovascular and pulmonary diseases. Reduced atmospheric oxygen pressure at increased altitude reduces oxygen availability and poses unique challenges during exercise. This review explores the physiological responses to exercise under acute and subacute exposure to hypoxia within the autonomic, pul…

Muscle-tendon vibration (MTV) has long been employed in both experimental and clinical settings, and its interest as a neurorehabilitation tool continues to grow. Yet, two primary physiological responses elicited by MTV, the tonic vibration reflex (TVR) and the kinaesthetic illusion (KI), remain inconsistently described across studies. This raises a fundamental limitation: how can vibration-induc…

Immune cells are critical for modulating inflammation and extracellular matrix remodelling for effective muscle regrowth following disuse atrophy. However, disrupted macrophage function and accumulation of cellular senescence may limit muscle recovery in ageing. The present study aimed to compare changes in the cellular dynamics of muscle macrophages, cellular senescence and collagen content duri…

Gestational diabetes mellitus (GDM) has traditionally been regarded as a transient metabolic disorder limited to pregnancy, with management directed primarily towards reducing obstetric and perinatal complications. Yet a growing body of evidence over the past two decades compels a fundamental redefinition. Two emerging paradigms expand the physiological and clinical understanding of GDM. The firs…

Fructose consumption has increased markedly over recent decades and has been consistently associated with the development of non-communicable chronic diseases, including impaired glycaemic homeostasis, type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD). Although the liver has historically been viewed as the primary organ mediating these effects, more recent evide…

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Brain injury in preterm infants is common but often difficult to detect in the early stages. The present study investigated whether evolving preterm brain injury after exposure to hypoxia-ischaemia (HI) is associated with dynamic changes in arterial blood pressure variability (BPV) and tested the hypothesis that it was mediated by alpha-adrenoreceptor activity. Chronically instrumented 0.7 gestat…

As a result of the electrotonic effect, under gap junction coupling, a critical number of excited cells is needed to elicit electrical conduction in cardiac tissue, a phenomenon called the source-sink effect. However, it is unclear how ephaptic coupling affects the source-sink effect. To address this issue, we carry out computer simulations to investigate the effects of ephaptic coupling and its …

Cardiac electrophysiology and mechanics are intrinsically linked via excitation–contraction coupling (ECC) on the one hand and mechano-electric coupling (MEC) on the other (Quinn & Kohl, 2021). Yet, despite numerous studies, there remain many open fundamental questions, especially at the whole organ level, regarding the role of electro-mechanical cross-talk in cardiac autoregulation, in arrhythmo…

Vascular cells continuously remodel the arterial wall (micro)structure in response to changes in their biomechanical/biochemical environment. Although the functional effects of arterial remodelling can be easily measured, assessing the underlying microstructural mechanisms is complex in vivo. Constitutive modelling is a computational technique that allows for linking whole-organ function to tissu…

Every physiology textbook and course teaches about homeostasis as a fundamental theory or organizing principle of physiology, and the predominating emphasis in teaching physiology is on the maintenance of a ‘stable internal milieu’ as originally articulated by Claude Bernard (1885). Despite the extraordinary impact of the theory of homeostasis, there are transformative life-cycle events that cann…

Transition of the fetus to extrauterine life requires increased cardiac workload and skeletal muscle activity, yet little is known about microvasculature growth during the perinatal period. We collected hindlimb skeletal muscles and cardiac left (LV) and right ventricles (RV) from fetal (135 days of gestational age; 135D) and neonatal (postnatal days 1 and 5; PD1 and PD5) lambs to measure vascula…

Calmodulin (CaM) is the principal calcium (Ca²⁺) sensor in eukaryotic cells, orchestrating hundreds of signalling pathways that regulate excitability, contraction, secretion, gene expression and many other essential processes. This small, highly conserved protein binds four Ca²⁺ ions and undergoes conformational changes that enable versatile interactions with a wide range of…

Delivery and utilisation of oxygen are critical determinants of skeletal muscle function, and therefore aerobic performance. Angiogenesis, the process of microvascular bed expansion, may be initiated by several tissue-level stimuli (e.g. of haemodynamic, myogenic or metabolic origin), which are typically present during dynamic exercise. Understanding the relative contribution of these distinct ph…

As the need to mobilize fuel from adipose tissue changes across a day, such as during the transition from the postprandial to postabsorptive state, the rate of lipolysis is accelerated to mobilize triacylglycerol from adipose tissue in the form of free fatty acids (FFAs) and glycerol. Following export of FFAs from the cell, these hydrophobic molecules face an aqueous environment in blood, where F…

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Muscle vibration alters both perceived limb position and velocity by increasing muscle spindle afferent firing rates. In particular the type Ia afferents are affected, which mainly encode muscle stretch velocity. Predictive frameworks of sensorimotor control, such as Active Inference and Optimal Feedback Control, suggest that velocity signals should inform position estimates. Such a function woul…

Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.