Both arginine (Arg) and its precursor citrulline (Cit) have received much interest during the past two decades because of their potential effects on whole‐body nitric oxide (NO) production and augmentation of NO‐dependent signaling pathways. However, the usefulness of Arg supplementation for NO production is questionable due to its high splanchnic first‐pass metabolism (FPM), which limits its systemic

Mitochondria are multifaceted organelles representing the “powerhouse of cells” for their function as bioenergetics and biosynthetic hubs. In addition, they play an essential role in the regulation of innate and adaptive immune responses, including host defenses against viruses, as well as in inflammatory responses 1. This peculiar role of mitochondria is principally due to the activation of adaptor

Chromogranin A (CgA), a 439‐residue long protein, is an important cardiovascular regulator and a precursor of various bio‐active fragments. Under stressful/pathological conditions, CgA cleavage generates the CgA1‐373 proangiogenic fragment. The present work investigated the possibility that human CgA1‐373 influences the mammalian cardiac performance, evaluating the role of its C‐terminal sequence.

Kidney research has been one major focus of publications of recent articles published in Acta physiologica. A number of articles deal with the elucidation of kidney disease models 1‐12 and the role of oxygen regulation in the kidney 13‐16. This contribution focusses on articles that deal with kidney disease models and in the second part on articles that are related to the topic hypoxia and oxygen regulation

Metabolic sources switch from carbohydrates in utero, to fatty acids after birth and then a mix once adults. O‐GlcNAcylation (O‐GlcNAc) is a post‐translational modification considered as a nutrient sensor. The purpose of this work was to assess changes in protein O‐GlcNAc levels, regulatory enzymes and metabolites during the first periods of life and decipher the impact of O‐GlcNAcylation on cardiac

MOG1 is a small protein that can bind to small GTPase RAN and regulate transport of RNA and proteins between the cytoplasm and nucleus. However, the in vivo physiological role of mog1 in the heart needs to be fully defined.

The importance of diagnostic imaging is undisputable for those practicing medicine or those experiencing medical practice as patients or their families. Who could ever imagine modern clinical medicine without imaging techniques such as X‐ray radiography, computed tomography, ultrasound and magnetic resonance imaging? Even microscopy is widely known as an indispensable tool for diagnostic histopathology

1 INTRODUCTION In the current issue of Acta Physiologica, Guessoum et al.1 address a question that has intrigued investigators for decades within kidney and blood pressure research fields. In conditions where the renin‐angiotensin aldosterone system (RAAS) is chronically challenged, the renin‐producing cells increase significantly in number and their localization expands from a juxtaglomerular position

In the presence of a metabolic acid‐base disorder, the kidney is called upon to compensate appropriately, altering the net acid excretion in urine. Metabolic acidosis is normally associated with urine acidification. This process can be appreciated through two different explanatory models. On the one hand, according to the widely adopted approach, pH regulation is achieved with proton (H+) removal through

Glycogen particles are found in different subcellular localizations, which are utilized heterogeneously in different fibre types during endurance exercise. Although resistance exercise typically involves only a moderate use of mixed muscle glycogen, the hypothesis of the present study was that high‐volume heavy‐load resistance exercise would mediate a pattern of substantial glycogen depletion in specific

Natriuretic peptides, BNP and ANP increase renal blood flow in experimental animals. The signaling pathway in human kidney vasculature is unknown. It was hypothesized that BNP and ANP cause endothelium‐independent relaxation of human intrarenal arteries by vascular natriuretic peptide receptor‐A, but not ‐B and ‐C, which is mimicked by agonists of soluble guanylyl cyclase sGC.

A growing body of evidence pointed correlation between insulin‐resistance, testosterone level and infertility, but there is scarce information about mechanisms. The aim of this study was to identify the possible mechanism linking the insulin‐resistance with testosterone‐producing‐Leydig‐cells functionality.

There is an increasing awareness of the impact of age and sex on cardiovascular diseases. Differences in physiology are suspected. Beta‐adrenoceptors (beta‐AR) are an important drug target in cardiovascular disease and potential differences might have significant impact on the treatment of many patients. To investigate whether age and sex affects beta‐AR function, we analyzed a large data set on beta‐AR‐induced

Abnormally activated vascular smooth muscle cells are key factors in pulmonary artery remodelling (PAR) and pulmonary artery hypertension (PAH). Keratin 1 is involved in inflammatory diseases; however, its role in PAH is unknown. We speculated that keratin 1 could regulate PASMCs and prevent PAH.

Reichmann et al. (this issue, 2020)1 show that histamine H3 receptor (Hrh3) antagonism or knockout (hrh3‐/‐) in zebrafish (Danio rerio) reduce aggressive behavior. With their projections all over the central nervous system in vertebrates, histaminergic neurons attract increasing attention in the pharmaceutical industry, especially for their inhibitory H3 receptors, coupled to Gi/o‐type proteins, autoreceptors

NG2 cells in the brain are comprised of pericytes and NG2 glia and play an important role in the execution of cerebral hypoxia responses, including the induction of erythropoietin (EPO) in pericytes. Oxygen‐dependent angiogenic responses are regulated by hypoxia‐inducible factor (HIF), the activity of which is controlled by prolyl 4‐hydroxylase domain (PHD) dioxygenases and the von Hippel‐Lindau (VHL)

Nicotinamide adenine dinucleotide (NAD) is an abundant cofactor that plays crucial roles in several cellular processes. NAD can be synthesized de novo starting with tryptophan, or from salvage pathways starting with NAD precursors like nicotinic acid (NA), nicotinamide (NAM) or nicotinamide riboside (NR), referred to as niacin/B3 vitamins, arising from dietary supply or from cellular NAD catabolism

Skeletal muscles of Body Builders (BB) represent an interesting model to study muscle mass gains in response to high volume resistance training. It is debated whether muscle contractile performance improves in proportion to mass. Here, we aim to assess whether muscle hypertrophy does not occur at the expense of performance.

By activating prostacyclin receptors (IP receptors), prostacyclin (PGI2) exerts cardiovascular protective effects such as vasodilation and inhibition of vascular smooth muscle cell (VSMC) proliferation. However, IP receptors are dysfunctional under pathological conditions, and PGI2 produces detrimental effects that are opposite to its physiological protective effects via thromboxane‐prostanoid (TP)

A long‐standing culinary practice is to sprinkle a little salt on fruits such as watermelon, tomatoes or cantaloupe to make them taste sweeter. In the current issue of Acta Physiologica, Yasumatsu et al. 1 describe a likely mechanism for this phenomenon. They report for the first time that the sodium‐glucose cotransporter 1 (SGLT1) is expressed in the apical membrane of sweet‐sensitive taste cells

Skeletal muscles are distributed throughout the body, presenting a variety of sizes, shapes and functions. Here, we examined whether muscle regeneration and atrophy occurred homogeneously throughout the body in mouse models.

In the pathogenesis of several diseases, neo‐angiogenesis is increased (e.g. tumour growth). The peptide L‐glutamyl‐L‐tryptophan (EW/IM862) has been claimed to exhibit inhibitory effects on tumour growth in vivo. However, the potential role of natural peptides with respect to anti‐angiogenic properties is unsettled. The current study explores anti‐angiogenic effects of the dipeptides WL, EW, IW and

The pathogenesis of obesity has been associated with high intake of dietary fat, and some recent studies have explored the cellular mechanisms of oro‐sensory detection of dietary fatty acids. We further assessed the role of transient receptor potential canonical (TRPC) channels in oro‐sensory perception of dietary lipids.

Small‐conductance Ca2+‐activated potassium (SK) channels are activated exclusively by increases in intracellular Ca2+ that binds to calmodulin constitutively associated with the channel. Wild‐type SK2 channels are activated by Ca2+ with an EC50 value of ~0.3 μmol/L. Here, we investigate hydrophobic interactions between the HA helix and the S4‐S5 linker as a major determinant of channel apparent Ca2+

Humans and other mammalian species possess an endogenous circadian clock system that has evolved in adaptation to periodically reoccurring environmental changes and drives rhythmic biological functions, as well as behavioural outputs with an approximately 24‐hour period. In mammals, body clocks are hierarchically organized, encompassing a so‐called pacemaker clock in the hypothalamic suprachiasmatic

Nature is full of miracles. One such phenomenon is the existence of enantiomers, molecules that are mirror images of each other. Chirality is widespread and stereoisomers exhibit similar physical and chemical properties, however, are not identical and may have strikingly different physiological effects. One example is Thalidomide, a sedative marketed as Contergan® from 1957 to 1961 by the German company

Loading‐induced tension development is often assumed to constitute an independent cue to initiate muscle protein synthesis following resistance exercise. However, with traditional physiological models of resistance exercise, changes in loading‐induced tension development also reflect changes in neural activation patterns, and direct evidence for a mechanosensitive mechanism is therefore limited. Here

This review examines kinetic properties and distribution of the 11 isoforms of myosin heavy chain (MyHC) expressed in extraocular muscle (EOM) fibre types and the regulation and function of these MyHCs. Although recruitment and discharge characteristics of ocular motoneurons during fixation and eye movements are well documented, work directly linking these properties with motor unit contractile speed

ATP‐binding cassette (ABC) transporters constitute a large group of plasma membrane proteins in mammals. In humans, ABC superfamily includes 48 members encoded by seven families of genes from ABCA to ABCG. Over the last two decades, ABC proteins have attracted considerable attention in pharmacological research as a result of the crucial role of some of them in the lack of response to chemotherapy and

Altered organization of the transverse‐tubular network is an early pathological event occurring even prior to the onset of heart failure. Such t‐tubular remodelling disturbs the synchrony and signalling between membranous and intracellular ion channels, exchangers, receptors and ATPases essential in the dynamics of excitation‐contraction coupling, leading to ionic abnormality and mechanical dysfunction

Aggression is a behavioural trait characterized by the intention to harm others for offensive or defensive purposes. Neurotransmitters such as serotonin and dopamine are important mediators of aggression. However, the physiological role of the histaminergic system during this behaviour is currently unclear. Here, we aimed to better understand histaminergic signalling during aggression by characterizing

Grasping physiology of intestinal electrolyte transport is the key to understand intestinal health, as shown by the article “Slc26a3 deletion alters pH‐microclimate, mucin biosynthesis, microbiome composition and increases Tnfα expression in murine colon” in this issue of Acta Physiologica1. The highlighted study is exemplary in showing that a variety of carriers and ion channels mediate intestinal

Currently, the Covid‐19 pandemic forces almost every country to take drastic measures to stop the spread of the virus. These include the avoidance of close contact with other humans, staying at home whenever possible and the closure of gyms or sport clubs. Now that people are more or less bound to their home, it is even more important to stay physically active. The occasional walks between sofa and

Citations to Acta Physiologica increase dramatically, reflecting the quality of the studies published. The build‐up of citations to Acta Physiologica since 2008 is seen in Figure 1. The 2019 ranking of Acta Physiologica remains constant, topping the list of those journals that publish articles from the entire field of physiology. When adding review journals and specialized journals in physiology (eg

We are confronted with the most dramatic pandemic world‐wide in the past 100 years. We are armed “to‐the‐teeth” compared to 1918, we know the agent, the genomic sequence, the bodily entry, the proliferation rate, the damage pathogenesis and the very nature of our enemy. We can identify its bodily presence and our resistance to it in terms of neutralizing antibody production. Nonetheless, the disease

Based on clinical and epidemiological investigations conducted so far, gender disparity exists in outcomes regarding Coronavirus disease 2019 (COVID‐19) affected patients as men show more serious forms and higher lethality than women.1 At present, mechanisms underlying the observed difference are not clear enough. The SARS‐CoV‐2 virus, responsible for COVID‐19, belongs to Coronavirus family and has

In the current issue of Acta Physiologica , Fan et al report that light activation enhances and prolongs the regenerative properties of adipose‐derived stromal/stem cells in a murine hindlimb ischaemia model through mechanisms involving secretion of angiogenic and vasculogenic factors.1 To understand why this finding merits a highlight, it helps to take a flashlight into the tunnels of time and get

It has long been known that cardiac myocytes release ATP, and that the release of ATP is increased in response to hypoxia and ischaemia.1 The mechanisms underlying that release and its regulation, however, remain unclear. In this issue of Acta Physiologica , Wang and colleagues from the Ballard laboratory present intriguing new evidence of a role for the cystic fibrosis transmembrane conductance regulator

The aim of the study was to investigate the role of cytochrome P450 (CYP) epoxygenase‐derived epoxyeicosatrienoic acids (EETs) in sustained hypoxic pulmonary vasoconstriction (HPV).

Despite advancements in management of acute myocardial infarction, this disease remains one of the leading causes of death. Timely reestablishment of epicardial coronary blood flow is the cornerstone of therapy; however, substantial amount of damage can occur as a consequence of cardiac ischaemia/reperfusion (I/R) injury. It has been previously proposed that the pathway leading to major cell death

The involvement of Septate Junctions (SJs) in critical cellular functions that extend beyond their role as diffusion barriers in the epithelia and the nervous system has made the fruit fly an ideal model for the study of human diseases associated with impaired Tight Junction (TJ) function. In this study, we summarized current knowledge of the Drosophila melanogaster SJ‐related proteins, focusing on

Hypomagnesaemia is a common feature of renal Na+ wasting disorders such as Gitelman and EAST/SeSAME syndrome. These genetic defects specifically affect Na+ reabsorption in the distal convoluted tubule, where Mg2+ reabsorption is tightly regulated. Apical uptake via TRPM6 Mg2+ channels and basolateral Mg2+ extrusion via a putative Na+‐Mg2+ exchanger determines Mg2+ reabsorption in the distal convoluted

The voltage‐gated sodium (NaV) channel is essential for cardiomyocyte function. It is responsible for generating the rising phase of the cardiac action potential. The channel consists of a pore‐forming, α‐subunit, whose main cardiac isoform is NaV1.5, and one or two associated β‐subunits. Moreover, it is part of a macromolecular complex including a diverse set of interacting proteins, some of which

Low skeletal muscle mass is highly prevalent in older cancer patients and affects 5% to 89% depending on the type and stage of cancer. Low skeletal muscle mass is associated with poor clinical outcomes such as post‐operative complications, chemotherapy toxicity and mortality in older cancer patients. Little is known about the mediating pathophysiological mechanisms. In this review, we summarize proposed

We investigated potential neuron types that code sugar information and how sodium‐glucose cotransporters (SGLTs) and T1Rs are involved.

The tools that have been used to assess the function of the vagus nerve lack specificity. This could explain discrepancies about the role of vagal gut‐brain signalling in long‐term control of energy balance. Here we use a validated approach to selectively ablate sensory vagal neurones that innervate the gut to determine the role of vagal gut‐brain signalling in the control of food intake, energy expenditure

Over the last two decades, an abundance of research has explored the impact of fatiguing locomotor exercise on the neuromuscular system. Neurostimulation techniques have been implemented prior to and following locomotor exercise tasks of a wide variety of intensities, durations, and modes. These techniques have allowed for the assessment of alterations occurring within the central nervous system and

Obesity has become a pandemic that affects all populations of all ages living in countries of all income levels.1 Attributed to sedentary lifestyle and energy dense diet, obesity is a risk factor for cardiovascular disease, insulin resistance, type 2 diabetes and even some types of cancer.2 These comorbidities also affect the immune system adversely and can exacerbate infectious diseases as observed

The new coronavirus SARS‐COV‐2 is currently impacting life around the globe.1 The rapid spread of this viral disease might be highly challenging for health care systems. This was seen in Northern Italy and in New York City for example.2 Governments reacted with different measures such as shutdown of all schools, universities and up to a general curfew. All of those measures have a huge impact on the

Tian and colleagues highlight the importance of right and left ventricular interdependence in their article in this issue of Acta Physiologica. The role of the right ventricle is often underestimated in health and disease. In comparison with the left ventricle, the right ventricle is triangular shaped, whereas the left ventricle is conical. Right ventricular function has been shown to be an important

In this issue of Acta Physiologia , Pallubinsky et al1 report that repeated moderate heat exposure has beneficial effects on blood glucose levels and insulin sensitivity in overweight, but otherwise healthy subjects, suggesting ambient temperature‐driven responses as efficient approach to the treatment of early diabetes symptoms. The obesity pandemic—and with it the rise of metabolic disorders such

Renin cells are essential for regulation of blood pressure and fluid‐electrolyte homeostasis. During homeostatic threat, the number of renin cells in the kidney increases, a process termed as recruitment. It has been proposed that recruitment occurs by proliferation, yet no systematic studies have been performed. We sought to determine the extent to which proliferation contributes to the recruitment

Exercise is a key component of a healthy lifestyle as it helps maintain a healthy body weight and reduces the risk of various morbidities and co‐morbidities. Exercise is an acute physiological stress that initiates a multitude of processes that attempt to restore physiological homeostasis and promote adaptation. A component of the stress response to exercise is the rapid release of hormones from the

Hypertension is the primary cause of cardiovascular mortality. Despite multiple existing treatments, only half of those with the disease achieve adequate control. Therefore, understanding the mechanisms causing hypertension is essential for the development of novel therapies. Many studies demonstrate that immune cell infiltration of the vessel wall, kidney and central nervous system, as well as their

Several Na+‐dependent phosphate cotransporters, namely NaPi‐IIb/SLC34A2, Pit‐1/SLC20A1 and Pit‐2/SLC20A2, are expressed at the apical membrane of enterocytes but their contribution to active absorption of phosphate is unclear. The aim of this study was to compare their pattern of mRNA expression along the small and large intestine and to analyse the effect of intestinal depletion of Pit‐2 on phosphate

The renin angiotensin system (RAS) plays an important role in the pathogenesis of variety of diseases. Targeting the formation and action of angiotensin II (Ang II), the main RAS peptide, has been the key therapeutic target for last three decades. ACE‐related carboxypeptidase (ACE2), a monocarboxypeptidase that had been discovered 20 years ago, is one of the catalytically most potent enzymes known

MRP2 is an intestinal ABC transporter that prevents the absorption of dietary xenobiotics. The aims of this work were: (1) to evaluate whether a short‐term regulation of intestinal MRP2 barrier function takes place in vivo after luminal incorporation of nutrients and (2) to explore the underlying mechanism.

Finally, I (PBP) discovered the right book for me. After starting a few other ones, putting them down, forcing myself to read on, taking another break, I abandoned the book pile with a bad conscious. After weeks of search, this is my page‐turner, keeping me up at night. It seems the book is rather special, being the story of a journalist's parents who meet in Norway during the Nazi occupation.1 What

FMS‐like receptor tyrosine kinase 3 (Flt3) has been reported to be increased in cardiomyocytes responding to ischaemic stress. This study was to determine whether Flt3 activation could ameliorate pressure overload‐induced heart hypertrophy and fibrosis, and to elucidate the mechanisms of action.