scholarly journals Sex differences in postsynaptic sweating and cutaneous vasodilation

2013 ◽  
Vol 114 (3) ◽  
pp. 394-401 ◽  
Author(s):  
Daniel Gagnon ◽  
Craig G. Crandall ◽  
Glen P. Kenny
Keyword(s):  
Sex Differences ◽  
Body Temperature ◽  
Dose Response ◽  
Direct Evidence ◽  
Passive Heating ◽  
Mean Body Temperature ◽  
Cutaneous Vasodilation ◽  
Males And Females ◽  
Sudomotor Activity ◽  
Change In Mean

The current study aimed to determine whether a peripheral modulation of sweating contributes to the lower sudomotor thermosensitivity previously observed in females during exercise. We examined dose-response relationships in 12 males and 12 females to incremental doses of acetylcholine (ACh) and methylcholine (MCh) for sweating (ventilated capsule), as well as to ACh and sodium nitroprusside (SNP) for cutaneous vasodilation (laser-Doppler). All drugs were infused using intradermal microdialysis. On a separate day, potential sex differences in the onset threshold and/or thermosensitivity of heat loss responses were assessed during progressive increases in mean body temperature elicited by passive heating. Increases in sweating as a function of increasing concentration of ACh ( P = 0.008) and MCh ( P = 0.046) significantly differed between males and females. Although the concentration eliciting 50% of the maximal sweating response did not differ between sexes for either agonist ( P > 0.1), maximum values were lower in females in response to ACh (0.34 ± 0.12 vs. 0.59 ± 0.19 mg·min−1·cm−2, P = 0.04) and MCh (0.48 ± 0.12 vs. 0.78 ± 0.26 mg·min−1·cm−2, P = 0.05). This observation was paralleled by a lower thermosensitivity of sudomotor activity in females during passive heating (1.29 ± 0.34 vs. 1.83 ± 0.33 mg·min−1·cm−2·°C−1, P = 0.03), with no significant differences in the change in mean body temperature at which onset of sweating occurred (0.85 ± 0.19 vs. 0.67 ± 0.13°C, P = 0.10). No sex differences in cutaneous vasodilation were observed in response to ACh and SNP, as well as during passive heating (all P > 0.1). These findings provide direct evidence for a peripheral modulation of sudomotor activity in females. In contrast, sex does not modulate cutaneous vasodilation.

Body cooling and response to heat

1961 ◽  
Vol 16 (2) ◽  
pp. 235-238 ◽  
Author(s):  
J. H. Veghte ◽  
Paul Webb
Keyword(s):  
Body Temperature ◽  
Water Immersion ◽  
Heat Exposure ◽  
The Body ◽  
Central Control ◽  
Mean Body Temperature ◽  
Gradient Effect ◽  
Sudomotor Activity ◽  
Body Cooling ◽  
High Level

Prior body cooling with cold air or water immersion increased human tolerance to a high level of heat stress. The lower the body temperature at the onset of the heat exposure, the greater the increase in tolerance times over the control values. Mean body temperature was the only discriminating criterion which successfully correlated with tolerance time in these experiments. Sudomotor activity in heat was inhibited by prior body cooling. It is postulated that the onset of sweating is due to a gradient effect, not to either peripheral or central control. Submitted on October 5, 1960

Disturbance of thermal homeostasis following dynamic exercise

2007 ◽  
Vol 32 (4) ◽  
pp. 818-831 ◽  
Author(s):  
Glen P. Kenny ◽  
Ollie Jay ◽  
W. Shane Journeay
Keyword(s):  
Body Temperature ◽  
Heat Loss ◽  
Core Body Temperature ◽  
Dynamic Exercise ◽  
Hemodynamic Changes ◽  
Post Exercise ◽  
Cutaneous Vasodilation ◽  
Baseline Values ◽  
Sudomotor Activity ◽  
Core Body

Recovery from dynamic exercise results in significant perturbations of thermoregulatory control. These perturbations evoke a prolonged elevation in core body temperature and a concomitant decrease in sweating, skin blood flow, and skin temperature to pre-exercise baseline values within the early stages of recovery. Cutaneous vasodilation and sweating are critical responses necessary for effective thermoregulation during heat stress in humans. The ability to modulate the rate of heat loss through adjustments in vasomotor and sudomotor activity is a fundamental mechanism of thermoregulatory homeostasis. There is a growing body of evidence in support of a possible relationship between hemodynamic changes postexercise and heat loss responses. Specifically, nonthermoregulatory factors, such as baroreceptors, associated with hemodynamic changes, influence the regulation of core body temperature during exercise recovery. The following review will examine the etiology of the post-exercise disturbance in thermal homeostasis and evaluate possible thermal and nonthermal factors associated with a prolonged hyperthermic state following exercise.

Influence of menstrual cycle on shivering, skin blood flow, and sweating responses measured at night

1985 ◽  
Vol 59 (6) ◽  
pp. 1902-1910 ◽  
Author(s):  
V. Hessemer ◽  
K. Bruck
Keyword(s):  
Blood Flow ◽  
Menstrual Cycle ◽  
Body Temperature ◽  
Sweat Rate ◽  
Serum Progesterone ◽  
Mean Body Temperature ◽  
Cutaneous Vasodilation ◽  
Threshold Temperatures ◽  
Early Follicular Phase ◽  
Heat Clearance

In 10 women, external cold and heat exposures were performed both in the middle of luteal phase (L) and in the early follicular phase (F) of the menstrual cycle. Serum progesterone concentrations in L and F averaged 46.0 and 0.9 nmol X l-1, respectively. The experiments took place between 3:00 and 4:30 A.M., when the L-F core temperature difference is maximal. At neutral ambient temperature, esophageal (Tes), tympanic (Tty), rectal (Tre), and mean skin (Tsk) temperatures averaged 0.59 degrees C higher in L than in F. The thresholds for shivering, chest sweating, and cutaneous vasodilation (heat clearance technique) at the thumb and forearm were increased in L by an average of 0.47 degrees C, related to mean body temperature [Tb(es) = 0.87Tes + 0.13 Tsk] and to Tes, Tty, Tre, or Tsk. The above-threshold chest sweat rate and cutaneous heat clearances at the thumb and forearm were also enhanced in L, when related to Tb(es) or time. The metabolic rate, arm blood flow, and heart rate at thermoneutral conditions were increased in L by 5.0%, 1.1 ml X 100 ml-1 X min-1, and 4.6 beats X min-1, respectively. The concomitant increase in threshold temperatures for all autonomic thermoregulatory responses in L supports the concept of a resetting of the set point underlying the basal body temperature elevation in L. The effects of the increased threshold temperatures are counteracted by enhanced heat loss responses.

Acetylcholine released from cholinergic nerves contributes to cutaneous vasodilation during heat stress

2002 ◽  
Vol 93 (6) ◽  
pp. 1947-1951 ◽  
Author(s):  
Manabu Shibasaki ◽  
Thad E. Wilson ◽  
Jian Cui ◽  
Craig G. Crandall
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
No Synthase ◽  
The Other ◽  
Whole Body ◽  
Cholinergic Nerves ◽  
Mean Body Temperature ◽  
Cutaneous Vasodilation ◽  
And Control ◽  
Treated Site

Nitric oxide (NO) contributes to active cutaneous vasodilation during a heat stress in humans. Given that acetylcholine is released from cholinergic nerves during whole body heating, coupled with evidence that acetylcholine causes vasodilation via NO mechanisms, it is possible that release of acetylcholine in the dermal space contributes to cutaneous vasodilation during a heat stress. To test this hypothesis, in seven subjects skin blood flow (SkBF) and sweat rate were simultaneously monitored over three microdialysis membranes placed in the dermal space of dorsal forearm skin. One membrane was perfused with the acetylcholinesterase inhibitor neostigmine (10 μM), the second membrane was perfused with the NO synthase inhibitor N G-nitro-l-arginine methyl ester (l-NAME; 10 mM) dissolved in the aforementioned neostigmine solution (l-NAMENeo), and the third membrane was perfused with Ringer solution as a control site. Each subject was exposed to ∼20 min of whole body heating via a water-perfused suit, which increased mean body temperature from 36.4 ± 0.1 to 37.5 ± 0.1°C ( P < 0.05). After the heat stress, SkBF at each site was normalized to its maximum value, identified by administration of 28 mM sodium nitroprusside. Mean body temperature threshold for cutaneous vasodilation was significantly lower at the neostigmine-treated site relative to the other sites (neostigmine: 36.6 ± 0.1°C, l-NAMENeo: 37.1 ± 0.1°C, control: 36.9 ± 0.1°C), whereas no significant threshold difference was observed between thel-NAMENeo-treated and control sites. At the end of the heat stress, SkBF was not different between the neostigmine-treated and control sites, whereas SkBF at thel-NAMENeo-treated site was significantly lower than the other sites. These results suggest that acetylcholine released from cholinergic nerves is capable of modulating cutaneous vasodilation via NO synthase mechanisms early in the heat stress but not after substantial cutaneous vasodilation.

scholarly journals Sex Difference in Self-Reported Sexual Functioning Among Frail Older Adults

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 313-313
Author(s):  
Brianne Olivieri-Mui ◽  
Sandra Shi ◽  
Ellen McCarthy ◽  
Dae Kim
Keyword(s):  
Older Adults ◽  
Logistic Regression ◽  
Sex Differences ◽  
Sexual Function ◽  
Older Adult ◽  
Sexual Functioning ◽  
Social Life ◽  
Well Being ◽  
Adult Males ◽  
Males And Females

Abstract Frailty may differentially impact how older adult males and females perceive sexual functioning, an important part of well-being. We assessed the level of frailty (robust, pre-frail, frail) for anyone with data on 11 sexual functioning questions asked in wave 2 of the National Social Life, Health, and Aging Project, 2010-2011 (n=2060). Questions covered five domains: overall sexual function (OSF), sexual function anxiety (SFA), changes in sexual function (CSF), erectile/vaginal dysfunction (EVD), and masturbation. Logistic regression identified sex differences in frailty and reporting worse sexual functioning. Linear regression predicted the number of domains reported as worse. Among males (n=1057), pre-frailty meant higher odds of reporting SFA (OR 1.8 95%CI 1.2-6.6), CSF (OR 1.7 95%CI 1.1-2.7), and EVD (OR 1.5 95%CI 1.0-2.2). Among females (n=1003), there was no difference in reporting by frailty. Females were more likely to report worse OSF (Robust: OR 7.4, 95%CI 4.8-11.4; Pre-frail: OR 6.2, 95%CI 3.9-9.9; Frail: OR 3.4 95%CI 1.7-6.6), but less likely to report SFA (Robust OR .3, 95%CI .2-.5; Pre-frail OR .2, 95%CI .1-.3; Frail OR .2 95%CI .1-.3). Pre-frail and frail females reported fewer domains as worse (Pre-frail coefficient -0.21 SE 0.09, Frail -0.43 SE 0.14). As frailty worsened, males reported more domains as worse (Pre-frail 0.24 SE 0.07, Frail 0.29 SE 0.08). Self-reported sexual functioning differs by sex at all levels of frailty, and reporting by males, but not females, changes with frailty. Providers should be aware that sexual functioning is of importance to both sexes despite varying degrees of frailty.

scholarly journals Stem cell treatment improves post stroke neurological outcomes: a comparative study in male and female rats

2021 ◽  
pp. svn-2020-000834
Author(s):  
Koteswara Rao Nalamolu ◽  
Bharath Chelluboina ◽  
Casimir A Fornal ◽  
Siva Reddy Challa ◽  
David M Pinson ◽  
...  
Keyword(s):  
Stem Cells ◽  
Sex Differences ◽  
Motor Function ◽  
Infarct Volume ◽  
Female Rats ◽  
Human Umbilical Cord ◽  
Male And Female ◽  
Post Stroke ◽  
Male And Female Rats ◽  
Males And Females

Background and purposeThe therapeutic potential of different stem cells for ischaemic stroke treatment is intriguing and somewhat controversial. Recent results from our laboratory have demonstrated the potential benefits of human umbilical cord blood-derived mesenchymal stem cells (MSC) in a rodent stroke model. We hypothesised that MSC treatment would effectively promote the recovery of sensory and motor function in both males and females, despite any apparent sex differences in post stroke brain injury.MethodsTransient focal cerebral ischaemia was induced in adult Sprague-Dawley rats by occlusion of the middle cerebral artery. Following the procedure, male and female rats of the untreated group were euthanised 1 day after reperfusion and their brains were used to estimate the resulting infarct volume and tissue swelling. Additional groups of stroke-induced male and female rats were treated with MSC or vehicle and were subsequently subjected to a battery of standard neurological/neurobehavioral tests (Modified Neurological Severity Score assessment, adhesive tape removal, beam walk and rotarod). The tests were administered at regular intervals (at days 1, 3, 5, 7 and 14) after reperfusion to determine the time course of neurological and functional recovery after stroke.ResultsThe infarct volume and extent of swelling of the ischaemic brain were similar in males and females. Despite similar pathological stroke lesions, the clinical manifestations of stroke were more pronounced in males than females, as indicated by the neurological scores and other tests. MSC treatment significantly improved the recovery of sensory and motor function in both sexes, and it demonstrated efficacy in both moderate stroke (females) and severe stroke (males).ConclusionsDespite sex differences in the severity of post stroke outcomes, MSC treatment promoted the recovery of sensory and motor function in male and female rats, suggesting that it may be a promising treatment for stroke.

scholarly journals OP0013 SEX DIFFERENCES IN AUTOIMMUNE DISEASE SUSCEPTIBILITY; A MULTI-OMIC APPROACH

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 8.1-8
Author(s):  
G. Robinson ◽  
K. Waddington ◽  
J. Peng ◽  
A. Radziszewska ◽  
H. Peckham ◽  
...  
Keyword(s):  
Sex Differences ◽  
Lipid Metabolism ◽  
Sex Hormones ◽  
Cell Function ◽  
Immune Cell ◽  
Density Lipoprotein ◽  
Hormone Treatment ◽  
Immune Cell Function ◽  
Immune Cell Subsets ◽  
Males And Females

Background:Males and females have altered immune responses resulting in variation in autoimmune and cardiovascular disease risk (CVR). Recently, these differences have played a role in the inflammatory response to COVID-19. Sex differences exist in the frequency and activity of immune-cell subsets but mechanisms underlying sexual dimorphism remain unknown. Juvenile-onset systemic lupus erythematosus (JSLE) is an autoimmune disorder that commonly emerges during puberty, has a strong female prevalence (female:male ratio, 4.5:1) and results in an increased CVR. JSLE is characterised by chronic inflammation and dyslipidaemia, where cardiovascular disease is a leading cause of mortality for patients. Our previous work identified a link between immune cell function and lipid metabolism in adult-onset SLE. We hypothesised that sex hormones could influence both lipid metabolism and immune cell function and this could determine sex-specific susceptibility to JSLE and associated CVR.Objectives:We investigated the role of sex hormones in modifying systemic lipid metabolism and inflammation.Methods:Nuclear magnetic resonance spectroscopy based serum metabolomics measuring over 130 lipoproteins (14-subsets with lipid compositions), flow cytometry measuring immune-cells, and RNA-sequencing were used to assess the metabolic and immune profile in young, pre/post-pubertal males (n=10/17) and females (n=10/23) and in individuals with gender-dysphoria (GD) under cross-hormone treatment (trans-male/female, n=26/25). This analysis was also performed on a cohort of post-pubertal male (n=12) and female (n=23) JSLE patients. Data was analysed by logistic regression, balanced random forest machine learning (BRF-ML), differential gene expression (DEG) and pathway analysis.Results:Post-pubertal males had significantly reduced cardio-protective high-density lipoprotein (HDL) subsets (p<0.0001) and increased cardio-pathogenic very-low-density lipoprotein subsets (p<0.0001) compared to females. These differences were not observed pre-puberty and were reversed significantly by cross-hormone treatment in GD individuals, suggesting that sex hormones regulate lipid metabolism in-vivo.BRF-ML (28 immune-cell subsets) identified an increased frequency of anti-inflammatory regulatory T-cells (Tregs) in post-pubertal males compared to females (p=0.0097). These Tregs were also more suppressive in males compared to females. Differences in Treg frequency were seen pre-puberty and were not altered by sex hormone treatment in GD individuals. However, Treg DEGs and functional transcriptomic pathways altered between post-pubertal males and females, including those involved in inflammatory signalling, overlapped with those altered by hormones in GD, suggesting hormones may also drive Treg functional changes. In addition, HDL metabolites modified by hormones showed differential associations with Treg phenotypes between post-pubertal males and females.Strikingly, sex differences in lipoproteins and Tregs were lost in JSLE, suggesting hormone signalling could be dysregulated in the pathogenesis of autoimmunity and could increase CVR for patients.Conclusion:Sex hormones drive altered lipoprotein metabolism and functional transcriptomic pathways in Tregs. Males have a lipoprotein profile associated with increased CVR, but a more anti-inflammatory immune profile compared to females. Together, this could explain sex differences in inflammatory disease susceptibilities and inform future sex-specific therapeutic strategies for the management of both JSLE and CVR.Acknowledgements:Lupus UKRosetrees TrustVersus ArthritisNIHR UCLH Biomedical Research CentreDisclosure of Interests:None declared

scholarly journals Sex differences in outcomes after arthroscopic bankart repair

2020 ◽  
Vol 6 (1) ◽  
pp. e000965
Author(s):  
Natalie A Lowenstein ◽  
Peter J Ostergaard ◽  
Daniel B Haber ◽  
Kirsten D Garvey ◽  
Elizabeth G Matzkin
Keyword(s):  
Mental Health ◽  
Sex Differences ◽  
Patient Reported Outcomes ◽  
Strength Function ◽  
Bankart Repair ◽  
Level Of Evidence ◽  
Arthroscopic Bankart Repair ◽  
Patient Reported ◽  
Males And Females

ObjectivesRisk factors for anterior shoulder dislocation include young age, contact activities and male sex. The influence of sex on patient-reported outcomes of arthroscopic Bankart repair (ABR) is unclear, with few studies reporting potential differences. This study’s purpose was to compare patient-reported outcomes of males and females following ABR.MethodsProspectively collected data was analysed for 281 patients (males: 206, females: 75) after ABR with preoperative, 1-year and 2-year follow-up responses. The Wilcoxon signed-rank and χ2 tests, preoperative, 1 year and 2 year follow-up results were examined to determine differences of scores in males versus females.ResultsNo statistically significant sex differences were observed in Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES), Visual Analogue Scale (VAS) or Single Assessment Numerical Evaluation (SANE) Scores at 1-year or 2-year follow-up. Females had lower Veterans RAND 12-item health survey (VR-12) mental health subscores at 2-year follow-up (females: 52.3±9.0, males: 55.8±7.6, p=0.0016). Females were more likely to report that treatment had ‘exceeded expectations’ at 2-year follow-up regarding motion, strength, function and normal sports activities.ConclusionResults of study demonstrate that ABR has similar outcomes for both males and females. There were no statistically significant sex-related differences in SST, ASES, VAS or SANE scores following ABR. VR-12 mental health subscores showed a minimal difference at 2-year follow-up, with lower scores in females.Level of evidenceRetrospective cohort study; level II.

scholarly journals No sex differences in learning in wild bumblebees

2021 ◽  
Author(s):  
Felicity Muth ◽  
Amber D Tripodi ◽  
Rene Bonilla ◽  
James P Strange ◽  
Anne S Leonard
Keyword(s):  
Sex Differences ◽  
Associative Learning ◽  
Sierra Nevada ◽  
Comparative Cognition ◽  
Natural Populations ◽  
Interspecific Variation ◽  
Learning Task ◽  
Learning Ability ◽  
Learning Performance ◽  
Males And Females

Abstract Females and males often face different sources of selection, resulting in dimorphism in morphological, physiological, and even cognitive traits. Sex differences are often studied in respect to spatial cognition, yet the different ecological roles of males and females might shape cognition in multiple ways. For example, in dietary generalist bumblebees (Bombus), the ability to learn associations is critical to female workers, who face informationally rich foraging scenarios as they collect nectar and pollen from thousands of flowers over a period of weeks to months to feed the colony. While male bumblebees likely need to learn associations as well, they only forage for themselves while searching for potential mates. It is thus less clear whether foraging males would benefit from the same associative learning performance as foraging females. In this system, as in others, cognitive performance is typically studied in lab-reared animals under captive conditions, which may not be representative of patterns in the wild. In the first test of sex and species differences in cognition using wild bumblebees, we compared the performance of Bombus vancouverensis nearcticus (formerly bifarius) and Bombus vosnesenskii of both sexes on an associative learning task at Sierra Nevada (CA) field sites. Across both species, we found that males and females did not differ in their ability to learn, although males were slower to respond to the sucrose reward. These results offer the first evidence from natural populations that male bumblebees may be equally as able to learn associations as females, supporting findings from captive colonies of commercial bees. The observed interspecific variation in learning ability opens the door to using the Bombus system to test hypotheses about comparative cognition.

Sign in / Sign up

Export Citation Format

Share Document