Experimental Physiology最新文献

{"title":"Regeneration of the lizard heart after cryoinjury.","authors":"Martina Gregorovicova, Barbora Sankova, Martin Bartos, Bjarke Jensen, Tobias Wang, David Sedmera","doi":"10.1113/EP093688","DOIUrl":"https://doi.org/10.1113/EP093688","url":null,"abstract":"<p><p>Lizards are renowned for their tremendous potential to heal tissues and organs after injury, but little is known about myocardial regeneration in reptiles generally. Here, we study cardiac regeneration in the leopard gecko (Eublepharis macularius) to fill the knowledge gap between traditional models of poikilothermic (zebrafish) and homeothermic (neonatal mice) vertebrates commonly used in myocardial regenerative studies. We inflicted cryoinjury at the apex of the adult heart and used optical mapping, microCT, histology and immunohistochemistry to evaluate myocardial regeneration over the following 4 weeks. Optical mapping revealed epicardial electrical activation of the ventricle during the healing period after cryoinjury, and demonstrated that the cryoinjured area was devoid of electrical activation during the first 2 weeks. The functional recovery of signal spreading over the whole ventricular surface was completed in 21 days after cryoinjury. Morphologically, the first week was characterized by a loss of myocardial viability, the second week by a restoration of the myocardial tissue, the third week by continuation of the regenerative processes, and the fourth week by a completion of myocardial regeneration and a restoration of heart viability. In conclusion, geckos may provide novel insight into myocardial healing across the vertebrate lineages and thus help to reveal healing abilities between non-ischaemic regenerative and ischaemic reparative processes during cardiac regeneration.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Daily hot-water immersion preserves altitude-induced haemoglobin mass expansion following descent independent of erythropoietin.","authors":"Elliott J Jenkins, Jodie L Koep, Andrew J M Douglas, Lauren E Maier, Connor A Howe, Sarah Sheitelman, Liam D Corr, Christoph Siebenmann, Michael G Hughes, Joshua C Tremblay, Philip N Ainslie, Travis D Gibbons, Mike Stembridge","doi":"10.1113/EP093944","DOIUrl":"https://doi.org/10.1113/EP093944","url":null,"abstract":"<p><p>High-altitude exposure increases haemoglobin mass (Hb_mass), a key determinant of arterial oxygen-carrying capacity, but following descent this adaptation can regress toward baseline within 7 days. Long-term heat acclimation has emerged as an alternative stimulus for Hb_mass expansion; however, whether post-altitude passive-heat exposure can preserve altitude-induced increases in Hb_mass remains unclear. Furthermore, the extent to which any preservation of Hb_mass is supported by sustained erythropoietin (EPO) production, and whether this support is mediated by plasma volume expansion or acute alterations in renal haemodynamics, has yet to be explored. Twenty-one healthy adults (8F) sojourned at 3800 m for 14 days and, following descent to 1250 m, were allocated to either hot-water immersion (HWI; 45 min at 40°C for 4 days; n = 11) or control (CON; n = 10). Hb_mass, intravascular volumes (carbon monoxide rebreathing) and circulating EPO were measured on high-altitude day 1 (HA1), day 14 (HA14), and post-descent day 5 (P5). Renal-artery blood velocity (Doppler-ultrasound) was measured before and after HWI on the day of descent. Hb_mass increased by 24 g [95% CI: 8, 40] across all participants during the altitude sojourn (P = 0.005). Following descent, Hb_mass decreased in CON (∆ = -18 g [95% CI: -36, 0], P = 0.045) but was maintained in HWI (∆ = +9 g [95% CI: -8, 26], P = 0.285). Circulating EPO declined after descent (P < 0.001) with no between-condition difference at P5 (P = 0.239), despite a transient reduction in renal-artery blood velocity following HWI (P = 0.025) and similar plasma volume expansion across groups (time: P < 0.001). Hot-water immersion offers a practical, lower-impact alternative to exercise-heat methods for preserving altitude-derived Hb_mass expansion, although the mechanisms underlying this response remain elusive.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence in contact sports research: Promise and peril for predicting and preventing brain injury.","authors":"Danny W Walmsley, Damian M Bailey","doi":"10.1113/EP093659","DOIUrl":"https://doi.org/10.1113/EP093659","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inflammation, mechanical allodynia and an exaggerated exercise pressor reflex during disease progression in UCD-type 2 diabetes mellitus rats.","authors":"Michelle L Harrison, Richard K McCuller, Yu Huo, Amshula N Gajula, Kai Ybarbo, Mark J Van Ryzin, Kimber L Stanhope, Peter J Havel, Audrey J Stone","doi":"10.1113/EP093516","DOIUrl":"https://doi.org/10.1113/EP093516","url":null,"abstract":"<p><p>Chronic low-grade inflammation characterizes type 2 diabetes mellitus (T2DM) and underlies the development of peripheral neuropathy, symptoms of which include mechanical allodynia and an exaggerated exercise pressor reflex. The purpose of this study was to determine whether mechanical allodynia and/or specific concentrations of inflammatory mediators coincide with the presence of an exaggerated exercise pressor reflex. Haemoglobin A1c was assessed to detect diabetes onset (threshold ≥5.6%) in male University of California Davis (UCD)-T2DM rats (n = 18). Age-matched, healthy Sprague-Dawley rats (n = 18) served as controls. Monthly measurements assessed mechanical allodynia (via paw withdrawal threshold), insulin and inflammatory mediators (via ELISA and multiplex kits). Paw withdrawal threshold was not different between groups prior to diabetes onset. However, by 8 weeks post-onset, T2DM rats demonstrated a significant decrease in pain threshold compared to that before diabetes onset, which persisted for 8 weeks. This is the same period in diabetes progression as when the exercise pressor reflex is exaggerated. Prior to diabetes onset, UCD‑T2DM rats had significantly higher circulating levels of IL‑6 and IL‑1β, and these elevations persisted throughout disease progression, with only CRP showing a significant increase at 8 weeks post‑onset. These findings offer a useful foundation for further exploration into the assessments of mechanical allodynia and inflammation to determine when those with T2DM are at an increased risk for experiencing adverse cardiovascular events.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147835555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the mechanism of control of the pulse rate.","authors":"Mark I M Noble, Angela J Drake-Holland","doi":"10.1113/EP093308","DOIUrl":"10.1113/EP093308","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2423-2425"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131061/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145767466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The physiology of survival: Breath-hold shallow-water diving.","authors":"Andrew H Baker, Ashley Jones, Adrian Mayhew, Carlene McAvoy, Ross Macleod, Hugh Montgomery, Craig Robertson, Jo Talbot, Mike Tipton","doi":"10.1113/EP093322","DOIUrl":"10.1113/EP093322","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2403-2410"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131091/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145767518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimated exercise-induced maximal myocardial blood flow in untrained and endurance-trained men.","authors":"Ilkka Heinonen, Kari K Kalliokoski, Juhani Knuuti, Marko S Laaksonen","doi":"10.1113/EP093307","DOIUrl":"10.1113/EP093307","url":null,"abstract":"<p><p>The heart critically depends on a continuous supply of oxygen, provided by myocardial blood flow (MBF), but reliable quantification of MBF during maximal exercise is not feasible in humans. We measured MBF at rest and during similar absolute (150 W) and relative (70% of <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${{dot{V}}_{{{{mathrm{O}}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> ) cycling exercise workloads in seven healthy untrained (UT) and seven healthy endurance-trained (ET) men by positron emission tomography and [¹⁵O]H₂O-tracer. The maximum MBF was extrapolated using the linear relationship between cardiac work load and MBF. MBF was also measured during intravenous infusion of standard high dose adenosine known to cause maximal vasodilation in the myocardial vasculature. Maximal exercise-induced MBF was calculated to be 5.0 ± 1.5 mL/g/min in UT and 4.5 ± 1.7 mL/g/min in ET (p = 0.6), which was 6.9-fold and 6.5-fold higher from their respective resting values. Adenosine-induced MBF was 3.9 ± 1.4 mL/g/min in UT and 2.3 ± 0.9 mL/g/min in ET, being significantly lower than maximal exercise-induced MBF in both groups. In addition, MBF was lower in the ET than in the UT group in both conditions. Myocardial vascular resistance responses and conclusions depended on whether the estimated maximal exercise calculations were based on mean arterial or systolic blood pressure estimations. This study thus demonstrates that estimated maximal MBF during exercise exceeds that achieved with adenosine infusion, and its increase from rest in humans may be higher than previously considered. Endurance training appears, however, not to increase peak MBF per gram of myocardium.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2543-2552"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131079/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147431656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerebral blood flow response to dynamic resistance exercise.","authors":"Stephanie Korad, Toby Mündel, Blake G Perry","doi":"10.1113/EP093313","DOIUrl":"10.1113/EP093313","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2426-2429"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131076/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of low-dose dopamine on exercise in fibrosing interstitial lung disease.","authors":"Charlotte Chen, Jui-Lin Fan, Michael Plunkett, Thalia Babbage, John Kolbe, Julian F R Paton, James P Fisher","doi":"10.1113/EP093092","DOIUrl":"10.1113/EP093092","url":null,"abstract":"<p><p>Fibrotic interstitial lung disease (FILD) is associated with dyspnoea and exercise intolerance. In other cardiorespiratory conditions, heightened carotid body (CB) chemoreflex sensitivity is associated with reduced exercise capacity. We tested the hypothesis that CB chemoreflex inhibition would improve exercise endurance time (EET) and reduce dyspnoea in FILD. In this randomised, single-blind study, 10 FILD patients (four women, 64 ± 8 years) completed the experimental procedures. Low-dose dopamine infusion (2 µg/kg/min) was used to inhibit the CB chemoreflex, and its effectiveness verified by measuring the hypoxic ventilatory response. Participants performed two constant work rate cycle exercise tests (75% of peak work rate) to exhaustion with either dopamine or saline as control. Dopamine suppressed the CB chemoreflex sensitivity in seven of the ten participants. Overall, dopamine reduced chemoreflex sensitivity by 27% relative to control (-0.646 ± 0.344 vs. -0.472 ± 0.410 L/min/%, P = 0.103). EET (saline 460 ± 411 s vs. dopamine 363 ± 182 s, P = 0.305) and exertional dyspnoea scores were similar between the conditions. Among those displaying reduced CB sensitivity with dopamine, there was a positive correlation between the magnitude of reduction in sensitivity and improvement in EET (r_s = 0.943, P = 0.005). Dopamine was associated with reduced blood pressure and increased heart rate. Although low-dose dopamine did not improve exercise capacity or dyspnoea in the group overall, subset analysis of those who achieved CB chemoreflex suppression (n = 7/10) with dopamine demonstrated a strong positive correlation between the reduction in sensitivity and EET improvement. This could suggest that the CB chemoreflex restrains exercise capacity in FILD.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2682-2695"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131104/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147510780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the statistical interpretation of ultrasound-based models predicting skeletal muscle fat infiltration.","authors":"Saul Martin-Rodriguez","doi":"10.1113/EP093815","DOIUrl":"10.1113/EP093815","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":"2729-2730"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13131071/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147618634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}