bluuebunny/crossref_metadata_2025_split huggingface dataset:
Renal Denervation Sensitizes Renal Resistance Arteries to L‐type Ca2+ Channel Activation
Authors: Grisk Olaf , Pfannkuch Saskia , Veltum Vanessa , Witte Jeannine 
Published: June 2021

We have shown that a depolarized vascular smooth muscle cell (VSMC) membrane potential sensitizes renal resistance arteries of sympathectomized rats to L‐type Ca2+‐channel activation. We tested if local renal denervation induces a similar alteration. Further, we investigated the contribution of ATP‐dependent potassium (KATP) channels for the regulation of renal resistance artery tone and tested if a depolarized VSMC membrane potential contributes to the increase in renal arterial norepinephrine (NE) sensitivity that develops after sympathectomy and renal denervation.Renal resistance arteries were obtained from rats that underwent neonatal sympathectomy, local renal denervation or respective sham‐treatments. In addition, interlobular and distal arcuate arteries were dissected from human kidney samples. Vessels were investigated by small vessel myography. Cumulative concentration‐response curves (CRCs) were obtained for the L‐type Ca2+ channel activator S‐(−)‐BayK8644 and NE in the absence or presence of glibenclamide (KATP channel blocker) and levcromakalim (KATP channel activator).Maximum S‐(−)‐BayK8644‐induced wall tension was 70% of maximum K+‐induced wall tension in arteries from sympathectomized and renal denervated rats vs. 30% of maximum K+‐induced wall tension in controls (p < 0.05). In human intrarenal arteries maximum S‐(−)‐BayK8644‐induced tension was 100% of K+‐induced tension. Levcromakalim (1 μM) abolished S‐(−)‐BayK8644 induced vasoconstrictions in rat and human arteries. Compared to respective controls, arteries from sympathectomized and renal denervated rats showed a leftward shift of the NE CRCs. Glibenclamide did not affect basal and NE‐induced wall tension in rat and human renal resistance arteries. Levcromakalim induced similar rightward shifts of the NE CRCs in vessels from sympathectomized, renal denervated and sham‐treated rats (DlogEC50 −0.58 – −0.27 M) and significantly blunted NE‐induced vasoconstrictions in human renal resistance arteries.L‐type Ca2+ channel activation is facilitated in renal resistance arteries of locally denervated kidneys suggesting that VSMC membrane potential is depolarized compared to VSMC from innervated kidneys. KATP channels are functional in rat and human renal resistance arteries. They play a minor role for the maintenance of basal tone but may mediate agonist‐induced vasodilation. The data further suggest that VSMC membrane potential depolarization does not significantly contribute to sympathectomy‐ and denervation‐induced NE supersensitivity in renal resistance arteries.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Effects of Sex and Histamine Receptor Blockade on Carotid Wave Intensity Before and After Exercise
Authors: Melendez ‐ Rosado Keyshla Marie , Yan Huimin 
Published: June 2021

Wave intensity analysis (WIA) is a hemodynamic index that assesses the working interaction between the heart and the arterial system. The first peak wave (W1) occurs during early systole and is associated with cardiac contractility. The second peak (W2) is associated with end systole/early diastole. A small backward‐traveling compression wave occurs after W1, referred as negative area (NA), caused by reflected waves from the peripheral (cerebral) vascular tone and resistance. There are two‐time components in WIA: R‐W1 corresponds to the pre‐ejection time and W1–W2 represents the ejection period. Recent evidence suggests that histamine receptor blockade may affect carotid arterial vessel vasodilation and arterial stiffness.PURPOSEThe purpose of this study was to explore the sex differences in carotid WIA at rest and following an acute bout of exercise both in the histamine receptor blockade and control conditions.METHODSForty‐nine healthy participants (males: n=23; females: n=26; 22 ± 1 years) were randomly assigned to either histamine receptor blockade or control placebo and underwent carotid WIA measurements at rest and at 30 (P30), 60 (P60), and 90 (P90) minutes following 45‐minute moderate intensity treadmill exercise. The effects of condition (blockade vs. control) and sex at rest were analyzed by two‐way repeated measures ANOVA. The effects of exercise, condition, and sex were analyzed by three‐way repeated measures ANOVA.RESULTSSee Table 1.CONCLUSIONSCardiac contractility is significantly increased in the histamine receptor blockade condition in men but not in women. Men also exhibit higher cerebral vascular resistance at rest. This may be associated with greater cardiovascular risk in young men compared to women, but requires further investigation.Support or Funding InformationAmerican Heart Association 12PRE9610007This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The influence of protease‐activated receptor 2 stimulation on cutaneous vascular and sweating responses during exercise in the heat in older males.
Authors: Meade Robert D. , Hatam Kion , Fujii Naoto , McGarr Gregory W. , Boulay Pierre , Sigal Ronald J. , Kenny Glen P. 
Published: June 2021

Stimulation of protease‐activated receptor 2 (PAR‐2), which is present on cutaneous epithelial cells and eccrine sweat glands, induces cutaneous vasodilation but not sweating in young adults during passive rest in a thermoneutral environment (~23°C). While recent data from our laboratory suggest that PAR‐2 activation does not influence these heat loss responses in young males during rest or exercise in a hot environment, it is unknown how stimulation of this receptor modulates cutaneous vasodilation and sweating in older males. Ten healthy older males (age: 61 ± 4 yrs) rested in a thermal chamber regulated to 25°C (baseline) while four microdialysis fibres were continuously perfused with 1) lactated Ringer's (Control) or the PAR‐2 receptor agonist SLIGKV‐NH2 at concentrations of 2) 0.05 mM, 3) 0.5 mM and 4) 5 mM. Chamber temperature was then increased to 40°C and, following ~60 min of passive heat exposure, participants performed 50‐min of moderate intensity cycling (200 W·m−2 of metabolic heat production). Local forearm cutaneous vascular conductance (CVC) and sweat rate were measured continuously at each treatment site. At baseline, CVC was elevated at the 5 mM SLIGKV‐NH2 skin site (40 ± 15%CVCmax) relative to Control (11 ± 4%CVCmax; P<0.01). By contrast, no differences were observed between treatment sites during passive exposure to 40°C (all P≥0.08) or at end‐exercise (all P≥0.22). Sweat rate was similar between treatment sites during both the baseline (all P≥0.53) and passive heat exposure (P≥0.28) periods. However, end‐exercise sweat rate was attenuated compared to Control (1.62 ± 0.30 mg·min−1·cm−2) with 0.05 mM (1.20 ± 0.29 mg·min−1·cm−2; P<0.01), 0.5 mM (1.12 ± 0.24 mg·min−1·cm−2; P<0.01) and 5 mM (1.15 ± 0.26 mg·min−1·cm−2; P=0.01) doses of SLIGKV‐NH2. These findings indicate that while PAR‐2 activation can cause cutaneous vasodilation during rest in thermoneutral conditions, its influence is diminished during both passive exposure and exercise in a hot environment. Further, in contrast to previous observations made in young adults, PAR‐2 activation diminished the sweating response in older males during exercise in the heat.Support or Funding InformationNatural Sciences and Engineering Research Council of Canada.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Discordant Vasomotor and Sudomotor Activity During Heat Stress in Persons with Spinal Cord Injury
Authors: Trbovich Michelle , Wu Yubo , Kellogg Dean 
Published: June 2021

ObjectivePersons with spinal cord injury (SCI) have compromised thermoregulatory vasomotor and sudomotor activity. During heat stress, impaired cutaneous vasodilation obviates skin blood flow (SkBF) increases and sweating responses (SR) are also impaired. Thus SCI persons have difficulty maintaining thermal homeostasis in heat stress. Our understanding of changes in the peripheral autonomic nervous system post SCI is incomplete. In non‐SCI persons, sympathetic cholinergic mechanisms effect increases in both SkBF and SR presumably through one set of nerves; however, definitive proof is lacking. Indeed, cholinergic vasodilator nerves and cholinergic sudomotor nerves could actually be anatomically separate. Interestingly, in the 1970s, it was reported that during heat stress, persons with complete SCI have skin regions where SkBF increases without concomitant SR increases and other regions where SR increases without concomitant SkBF increases. These results suggest that efferent cholinergic sympathetic vasomotor nerves and efferent cholinergic sympathetic sudomotor nerves are separate.MethodsThree persons (C4 AIS B/tetraplegia, T8 AIS A/paraplegia and able‐bodied) underwent indirect heat stress until core temperature (Tcore) rose 0.8°C. Areas 10 cm above and 20 cm below neurological level of injury (NLOI) of SCI persons were left uncovered so as to avoid local heating effects. After Tcore elevation, SkBF responses were measured by laser Doppler imaging (LDI) while SR were assessed via the starch iodine test.ResultsThe person with tetraplegia showed increases in SkBF as indexed by LDI both above and below the NLOI down to T2 dermatomal level but demonstrated no intact SR areas. The person with paraplegia demonstrated increased SR down to T9 and increases in SkBF down to T12 dermatomal levels. Finally, the able‐bodied (AB) person LDI scan from the T6 to T12 dermatomal levels demonstrated intact SkBF and intact SR throughout the entire area. In both SCI persons, the skin areas of preserved SkBF responses were discordant with those of SR during heat stress. The AB person demonstrated no discordant responses as SkBF and SR.ConclusionThis pilot data confirms discordant SkBF and SR responses in persons with tetraplegia and paraplegia and demonstrates that SCI persons can serve as a model to further investigate the neurological reflex controls of SkBF and SR during heat stress. Furthermore, these data suggests that cholinergic sympathetic vasomotor nerves and efferent cholinergic sympathetic sudomotor nerves may be separate.Support or Funding InformationVeteran's Affairs Rehabilitation Research and Development, Career Development AwardThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Weight maintenance diets prevent short‐term physical inactivity‐induced glycemic dysregulation in young healthy subjects
Authors: Winn Nathan C. , Pettit‐Mee Ryan , Walsh Lauren K. , Restaino Robert M. , Ready Sean T. , Padilla Jaume , Kanaley Jill A. 
Published: June 2021

BackgroundReduced physical activity is generally associated with disruptions in glucose metabolism and increased accumulation of adiposity. However, whether these adverse effects of physical inactivity manifest when individuals are maintained in energy balance is unknown. Thus, this study examined whether weight maintenance diets prevent physical inactivity‐induced metabolic dysfunction in healthy active adults.DesignTen lean young adults (24±1 year; 25±1 kg/m2) consumed a control (64% carbohydrate, 20% fat, 16% protein) and higher‐protein diet (50% carbohydrate, 20% fat, 30% protein) during ten days of reduced ambulatory activity (>10,000 → ~5,000 steps/day) in a randomized cross‐over design. To mimic the typical Western lifestyle, a subset of male subjects (n=5) completed a 3rd ten‐day physical inactivity trial while consuming 35% excess of their basal energy requirements.ResultsDuring inactivity, daily steps and activity‐associated energy expenditure were decreased by ~65% (P<0.05) and this led to a reduction in maximal aerobic capacity (−1.8±0.7 ml/kg/min, P=0.004), independent of diet conditions. Fat free mass tended to decrease following inactivity (P=0.06), despite no change in body fat percentage or fat mass. Fasting glucose, but not fasting insulin levels, were lowered by physical inactivity, with no differences between diet conditions. Both diets prevented physical inactivity‐induced disruptions in postprandial glucose, insulin, and nonesterified fatty acids in response to a 75‐g oral glucose load (AUC, P>0.05). Overfeeding + physical inactivity increased body weight, body fat percentage, and fat mass (P>0.05). Moreover, fasting glucose, insulin, and 2‐hour postprandial glucose and insulin levels were significantly elevated (P<0.05). Surrogate markers of insulin sensitivity (QUICKI) and insulin resistance (HOMA‐IR) were decreased and increased, respectively after overfeeding + inactivity, despite no changes in blood lipid concentrations.ConclusionsMetabolic disruptions associated with physical inactivity are absent in healthy subjects consuming weight maintenance diets. These findings suggest that small changes in feeding behavior aimed at preventing weight gain is a viable strategy to protect against inactivity‐induced metabolic dysfunction.Support or Funding InformationAmerican Egg Board (#00050021 to NCW; JAK, sponsor)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Impact of Chronic Omega‐3 Polyunsaturated Fatty Acids Supplementation and Aerobic Training on Oxidative Stress Markers in Obese Women
Authors: Koozehchian Majid S. , Abdi Ahmad , Mehrabani Javad , Maryam Kaveh B , Earnest Conrad P. 
Published: June 2021

PURPOSEIncreased intake of omega‐3 polyunsaturated fatty acids (n−3 PUFA) appear to have antioxidant properties. The purpose of this study was to examine the chronic effect of n−3 PUFA supplementation and aerobic training on oxidative stress markers in obese women.METHODSWe performed a randomized, placebo‐controlled, double‐blind design on 43 obese women (48.5±2y; 39.7±5% body fat, 33.8±3 kg/m2, Supplement [SUP] n=11, Aerobic Training [AT] n=12, Supplement‐Aerobic Training [SAT] n=11, and Placebo [PLA] n=9). Oxidative stress markers including total antioxidant capacity (TAC), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were measured at baseline and at week 8. All participants were asked to maintain their normal dietary intake throughout study. Participants in AT and SAT groups were required to follow an aerobic training program which was 45‐min running on the treadmill with 45–65% HRmax (3 d/wk) for an 8‐wk period, while the SUP and PLA groups did not perform any training program. Participants received either 4 g of fish oil (56% docosahexaenoic acid (DHA) and 28% eicosapentaenoic acid (EPA) or placebo (olive oil) in four divided doses per day for an 8‐week period. Data were analyzed by GLM and presented as mean (SD).RESULTSWe observed a significant increase in serum TAC in SUP and SAT groups, but not in AT and PLA groups (p<0.04). The level of CAT was significantly higher only in SAT, but not in any other groups (p<0.01). We did not observe any significant change in serum SOD and GPx levels among the groups (p>0.05).CONCLUSIONThe present findings suggest that 4 g/day of fish oil for an 8‐week period, increase the activity of TAC and antioxidant enzymes. Fish oil supplementation might be considered as a protective strategy to improve the status of antioxidant defense system in obese women.Support or Funding InformationThis study was not funded.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Exploring Perception and Acceptance of Edible Insects as a Protein Source
Authors: Atakan S. Sinem , Wansink Brian 
Published: June 2021

Edible insects are increasingly getting attention as an attractive source of protein due to their high protein quality and sustainability of their production compared to traditional sources of meat. However, consumers, especially Western consumers, may be aversive to eating insects (Tan et al., 2015). In order to encourage consumers towards sustainable sources of protein, it is crucial to examine the factors that shape consumers perception of edible insects.The goal of this research is to understand which factors affect acceptance of different protein sources, more specifically insect protein. In order to do so, we compared perceptions of protein bars with one of the three labels (insect, soy, or whey) in an exploratory experiment (N=78).The experiment was a 3 (protein type: whey vs. soy vs. insect) × 2 (order: evaluate‐taste vs. taste‐evaluate) between subjects design. In the experiment, one third of the participants were told that the protein bar sample they received had 10 grams of protein vs. soy protein vs. insect protein. All of the samples were from identical protein bars and had only regular whey protein. In addition, half of the participant first tasted the sample and then evaluated the sample (taste‐evaluate condition). The other half first evaluated the sample, then tasted it, and then evaluated the bar again (evaluate‐taste condition).In the taste‐evaluate condition, all the three samples had identical evaluations. Participants did not indicate any differences in terms of taste or texture among the three protein sources when they sampled the bar before they answered the questions. They all thought that they would enjoy the protein bar at similar levels. However, in the evaluate first and then taste condition, contradictory to what previous research suggests, the sample protein bar with the insect protein label had higher evaluations in terms of both expected and actual taste. Simply labeling the protein bar sample as having insect protein enhanced its evaluations.The results from our study challenge the common belief that Western consumers are likely to reject eating insects. Future studies will explore which specific factors encourage consumers to evaluate foods with insect protein as more favorable.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Role of Melanocortin‐4 Receptor Activation in Hypertension Induced by Chronic Intermittent Hypoxia
Authors: Maok Sydney P. , da Silva Alexandre A. , Hall John E. , do Carmo Jussara M. 
Published: June 2021

Obesity is often associated with chronic intermittent hypoxia (CIH), increased sympathetic nervous system (SNS) activity and hypertension (HT). We previously demonstrated that melanocortin 4 receptors (MC4R) play a key role in regulating blood pressure (BP) in obesity and other conditions associated with increased SNS activity. In this study we examined if activation of CNS MC4R contributes to CIH‐induced HT. Wild‐type (WT, n=6), obese MC4R knockout (MC4R‐KO, n=5) and lean pair‐weighted (PW) MC4R‐KO (n=5) rats were instrumented with telemetry probes for measurement of mean arterial pressure (MAP) and heart rate (HR) 24‐hrs/day. The rats were exposed to CIH (8 hrs/day from 8:00–16:00 hours for 7 consecutive days). CIH significantly reduced food intake in obese MC4R‐KO rats by 50% leading to net cumulative reduction of −108±13 g compared to a −33±3 g cumulative food intake reduction in control WT rats. Food intake was kept at baseline values and was not altered by CIH in PW‐MC4RKO rats. Body weight was reduced by 7.5, 12.0 and 3.5 % in obese MC4R‐KO, WT and lean PW‐MC4R‐KO rats, respectively. CIH did not significantly alter plasma glucose concentration in MC4R‐KO or WT rats. However, CIH reduced plasma leptin concentration in obese MC4R‐KO rats (12±2 vs. 18±2 ng/mL during control period) while increasing leptin concentration in WT rats (1.8±0.5 vs. 0.9±0.1 ng/mL). CIH reduced fasting insulin concentration in WT rats (7±2 vs. 15±3 mU/mL) but did not alter insulin in MC4R‐KO rats (67±7 vs. 71±14 mU/mL). Baseline MAP was higher in obese and lean PW‐MC4R‐KO compared to WT rats (114±4, 112±2 and 107±2 mmHg), and CIH significantly increased MAP by approximately 11, 6 and 9 mmHg, respectively. Baseline HR was not different in obese MC4R‐KO and control rats (314±3 and 321±5 bpm), but lean PW‐MC4R‐KO had significantly lower HR (291±8 bpm). These results suggest that obesity and CNS melanocortin system may interact in complex ways to elevate BP during CIH. (NHLBI‐PO1HL51971, NIGMS P20GM104357)Support or Funding InformationDepartment of Physiology and Biophysics and Mississippi Center for Obesity Research. University of Mississippi Medical Center, Jackson, MS.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Chronic Intermittent Hypoxia Causes Cellular Hypoxia in the Hippocampus
Authors: Khuu Maggie A. , Nallamothu Thara , Garcia Alfredo J. 
Published: June 2021

The hippocampus is a brain structure frequently affected in individuals suffering from sleep apnea. Although hypoxia is a well‐recognized environmental change that negatively impacts hippocampal neurophysiology, it is unclear whether brief periods of hypoxia experienced during sleep apnea are sufficient for producing cellular hypoxia. We conducted immunohistochemical studies in tissue harvested from mice (P30–P50) exposed to 0 or 10 days of intermittent hypoxia (IH) to address this issue. Staining for protein adducts of reductively activated 2‐nitroimidazoles was used as marker for cellular hypoxia. Our ongoing experiments indicate that IH causes an increase in the number of hypoxic cells restricted primarily to the granular cell layer and subgranular zone of the dentate gyrus. While these findings suggest that cellular hypoxia caused by IH exposure may not be widespread throughout the hippocampus, we propose that increased cellular hypoxia in the dentate gyrus may contribute to changes in adult neurogenesis and synaptic plasticity in this area critical to cognition.Support or Funding InformationFaculty Diversity Career Advancement GrantThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.