Journal of applied physiology: respiratory, environmental and exercise physiology最新文献_第3页

Estimation of isogravimetric capillary pressure by a filtration method in skeletal muscle and lung. 用过滤法估计骨骼肌和肺等重毛细管压力。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1817

R J Korthuis, M I Townsley, B Rippe, A E Taylor

引用次数: 0

Surrounding structures affect pressure-diameter behavior of excised dog bronchi. 周围结构影响狗切除支气管的压力-直径行为。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1632

M Nakamura, D L Luchtel, Y Ikeda, H Sasaki, T Okubo, T Takishima, J Hildebrandt

{"title":"Surrounding structures affect pressure-diameter behavior of excised dog bronchi.","authors":"M Nakamura, D L Luchtel, Y Ikeda, H Sasaki, T Okubo, T Takishima, J Hildebrandt","doi":"10.1152/jappl.1984.57.6.1632","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1632","url":null,"abstract":"The effects of adjacent large blood vessels, fibroelastic membrane, and parenchyma on pressure-diameter (P-D) behavior of intrapulmonary bronchi were studied in five dog lung lobes. Central lobar airways were inflated separately by blocking all branches with beads and inflating the distal lobar air spaces via pleural capsules. After bronchial P-D curves were obtained at fixed pleural pressures (Ppl) of -30, -10, and -5 cmH2O, the P-D properties of the isolated bronchi were measured in each of four stages of dissection: 1) lobar artery and vein were left attached to the bronchus, but parenchyma was removed to within 1-2 mm of the limiting membranes; 2) all remaining parenchyma was carefully removed; 3) the large vessels were removed, leaving the bronchial fibroelastic membrane intact; and 4) the fibroelastic membrane was peeled from the bronchus. From stage 1 it was deduced that in the intact lobes, peak peribronchial parenchymal stress (Px) averaged -29.2 cmH2O at Ppl = -30 cmH2O). In stage 2 bronchial recoil was reduced only approximately 5%. The major decrease (approximately 35%) occurred in stage 3, indicating that interaction between vessels and bronchi contributed significantly to bronchial stiffness. A final decrease of approximately 10% was seen in stage 4. We conclude that Px in the intact state is similar to Ppl at a transpulmonary pressure of 30 cmH2O and that stages 1 or 2 may provide a better basis for estimating Px than the commonly employed bronchus free of vessels and tissue.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1632-9"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1632","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17567870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Effect of a 42.2-km footrace and subsequent rest or exercise on muscular strength and work capacity. 42.2公里的跑步和随后的休息或锻炼对肌肉力量和工作能力的影响。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1668

W M Sherman, L E Armstrong, T M Murray, F C Hagerman, D L Costill, R C Staron, J L Ivy

{"title":"Effect of a 42.2-km footrace and subsequent rest or exercise on muscular strength and work capacity.","authors":"W M Sherman, L E Armstrong, T M Murray, F C Hagerman, D L Costill, R C Staron, J L Ivy","doi":"10.1152/jappl.1984.57.6.1668","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1668","url":null,"abstract":"This study 1) quantitates the effect of a 42.2-km footrace (marathon) on leg extensor strength (maximal peak torque, MPT) and work capacity (WC, measured during a leg extensor fatigue test), and 2) describes the effect of either a rest or exercise regimen for 1 wk after the marathon on the recovery of MPT and WC. Ten trained male runners performed personal records in a marathon and were then randomly assigned to either a rest or exercise-recovery group. The rest group did not train, whereas the exercise group ran 20-45 min/day at their selected intensity of exercise [50-60% maximal O2 consumption (Vo2max)] during the recovery week. MPT was measured at 1.1, 3.2, and 5.3 rad X s-1. The total work generated during a 50-contraction active extension-passive flexion fatigue test conducted at 3.2 rad X s-1 was defined as WC. Reports of perceived soreness of the quadriceps were obtained before each strength-testing session. These measurements were obtained before the marathon and 15-20 min and 1, 3, 5, and 7 days postmarathon. A significant reduction in MPT and WC resulted and continued 1 day postmarathon. MPT of both groups improved through day 5 postmarathon at 1.1 and 3.2 rad X s-1. MPT of the rest group improved through day 7 postmarathon but remained less than premarathon MPT. Recovery of MPT was impaired in the exercise group through days 5-7 postmarathon after 40-45 min exercise at 60% Vo2max. WC was recovered 3 days postmarathon in the rest group but was still impaired 7 days postmarathon in the exercise group.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1668-73"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1668","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17567874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 105

Pharyngeal airway-stabilizing function of sternohyoid and sternothyroid muscles in the rabbit. 兔胸骨舌骨肌和胸骨甲状腺肌的咽道稳定功能。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1790

J L Roberts, W R Reed, B T Thach

{"title":"Pharyngeal airway-stabilizing function of sternohyoid and sternothyroid muscles in the rabbit.","authors":"J L Roberts, W R Reed, B T Thach","doi":"10.1152/jappl.1984.57.6.1790","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1790","url":null,"abstract":"The upper airway is vulnerable to collapse from negative intraluminal pressures during inspiration. The tongue muscles, the genioglossi and geniohyoids, by contracting during inspiration, appear to function to resist this collapse. This study supports the hypothesis that two cervical strap muscles, the sternohyoid and sternothyroid, have a similar function. First, phasic inspiratory electromyographic activity was recorded from the sternohyoid and sternothyroid muscles of nine anesthetized rabbits during tidal breathing. Furthermore, each muscle showed a progressive increase in electromyographic activity with airway occlusion. Second, in eight rabbits, by determining the amount of negative pressure required to collapse the upper airway (airway closing pressure determination), it was shown that upper airway stability improved with electrical stimulation of either the paired sternohyoid or sternothyroid muscles. In addition, in 12 freshly killed rabbits, mechanical tension, mimicking the contraction of either the sternohyoid or sternothyroid, improved airway stability. Finally, observations of the pharyngeal lumen utilizing a fiber-optic endoscope, revealed concentric narrowing of the oro- and nasopharynx when airway pressure was lowered and concentric widening when tension was increased in the sternohyoid or sternothyroid muscles. These findings support the hypothesis that phasic inspiratory contraction of the sternohyoid and sternothyroid muscles functions to resist pharyngeal airway collapse due to negative intraluminal pressures.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1790-5"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1790","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17569531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 66

Near-maximal voluntary hyperpnea and ventilatory muscle function. 接近最大的自主呼吸急促和通气肌功能。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1742

T R Bai, B J Rabinovitch, R L Pardy

{"title":"Near-maximal voluntary hyperpnea and ventilatory muscle function.","authors":"T R Bai, B J Rabinovitch, R L Pardy","doi":"10.1152/jappl.1984.57.6.1742","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1742","url":null,"abstract":"Because of its potential relevance to heavy exercise we studied the ventilatory muscle function of five normal subjects before, during, and after shortterm near-maximal voluntary normocapnic hyperpnea. Measurements of pleural and abdominal pressures and diaphragm electromyogram (EMG) during hyperpnea and of maximum respiratory pressures before and after hyperpnea were made at four levels of ventilation: 76, 79, and 86% maximal voluntary ventilation (MVV) and at MVV. Measurements of pleural and abdominal pressures and diaphragm electromyogram (EMG) during hyperpnea and of maximum respiratory pressures before and after hyperpnea were made. The pressure-stimulation frequency relationship of the diaphragm obtained by unilateral transcutaneous phrenic nerve stimulation was studied in two subjects before and after hyperpnea. Decreases in maximal inspiratory (PImax) and transdiaphragmatic (Pdimax) strength were recorded posthyperpnea at 76 and 79% MVV. Decreases in the pressure-frequency curves of the diaphragm and the ratio of high-to-low frequency power of the diaphragm EMG occurred in association with decreases in Pdimax. Analysis of the pressure-time product (P X dt) for the inspiratory and expiratory muscles individually indicated the increasing contribution of expiratory muscle force to the attainment of higher levels of ventilation. Demonstrable ventilatory muscle fatigue may limit endurance at high levels of ventilation.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1742-8"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1742","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17570738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 68

Time course of loss of adaptations after stopping prolonged intense endurance training. 停止长时间高强度耐力训练后适应性丧失的时间过程。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1857

E F Coyle, W H Martin, D R Sinacore, M J Joyner, J M Hagberg, J O Holloszy

{"title":"Time course of loss of adaptations after stopping prolonged intense endurance training.","authors":"E F Coyle, W H Martin, D R Sinacore, M J Joyner, J M Hagberg, J O Holloszy","doi":"10.1152/jappl.1984.57.6.1857","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1857","url":null,"abstract":"Seven endurance exercise-trained subjects were studied 12, 21, 56, and 84 days after cessation of training. Maximal O2 uptake (VO2 max) declined 7% (P less than 0.05) during the first 21 days of inactivity and stabilized after 56 days at a level 16% (P less than 0.05) below the initial trained value. After 84 days of detraining the experimental subjects still had a higher VO2 max than did eight sedentary control subjects who had never trained (50.8 vs. 43.3 ml X kg-1 X min-1), due primarily to a larger arterial-mixed venous O2 (a-vO2) difference. Stroke volume (SV) during exercise was high initially and declined during the early detraining period to a level not different from control. Skeletal muscle capillarization did not decline with inactivity and remained 50% above (P less than 0.05) sedentary control. Citrate synthase and succinate dehydrogenase activities in muscle declined with a half-time of 12 days and stabilized at levels 50% above sedentary control (P less than 0.05). The initial decline in VO2 max was related to a reduced SV and the later decline to a reduced a-vO2 difference. Muscle capillarization and oxidative enzyme activity remained above sedentary levels and this may help explain why a-vO2 difference and VO2 max after 84 days of detraining were still higher than in untrained subjects.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1857-64"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1857","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17567653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 384

Regional differences in expansion in excised dog lung lobes. 犬肺叶切除后扩张的区域差异。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1710

L E Olson, J R Rodarte

{"title":"Regional differences in expansion in excised dog lung lobes.","authors":"L E Olson, J R Rodarte","doi":"10.1152/jappl.1984.57.6.1710","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1710","url":null,"abstract":"The position of small metallic markers embedded within the lung parenchyma and glued to the pleural surface of four excised right caudal dog lobes were determined during stepwise deflation from an airway opening pressure of 25 cmH2O in air-filled suspended lobes and 8 cmH2O in saline-filled lobes submerged in saline. Changes in the volumes of tetrahedrons formed by four noncoplanar markers were taken as regional lung volume changes at the centroids of the tetrahedron. In both air- and saline-filled lobes at all volumes below total lobe capacity (TLC) there was considerable variability in regional volume. The variability occurred at the first step below TLC and increased with deflation. Regions behaved consistently; regions that were proportionally larger or smaller than the overall lobe at any step tended to be larger or smaller, respectively, at all steps. There was a significant correlation between the regional behavior of the air- and saline-filled lobes. The variability of regional volume did not follow any clear topographical orientation. These results indicate there is considerable variability of lung compliance within small regions. This heterogeneity of regional parenchymal properties may be the anatomical basis of the nonuniformity of regional ventilation known to occur in intact animals and excised lobes within small regions at the same vertical height.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1710-4"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1710","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17570734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 41

Predictability of skeletal muscle tension from architectural determinations in guinea pig hindlimbs. 豚鼠后肢结构决定对骨骼肌张力的可预测性。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1715

P L Powell, R R Roy, P Kanim, M A Bello, V R Edgerton

{"title":"Predictability of skeletal muscle tension from architectural determinations in guinea pig hindlimbs.","authors":"P L Powell, R R Roy, P Kanim, M A Bello, V R Edgerton","doi":"10.1152/jappl.1984.57.6.1715","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1715","url":null,"abstract":"The maximum tetanic tension (Po) generated by a skeletal muscle is determined by its functional cross-sectional area (CSA) and its specific tension (tension/CSA). Measurements of average fiber length (normalized to a sarcomere length of 2.2 micron), muscle mass, and approximate angle of pinnation of muscle fibers within a muscle were taken from 26 different guinea pig hindlimb muscles and were used to calculate CSA. The specific tension was assumed to be 22.5 N X cm-2 and was used to determine the estimated Po of each muscle studied. In a second group of guinea pigs the in situ Po of 11 selected hindlimb muscles and muscle groups were determined. Estimated and measured Po values were found to have a strong linear relationship (r = 0.99) for muscle and muscle groups tested. The specific tension of the soleus, a homogeneously slow-twitch muscle, was shown to be approximately 15.4 N X cm-2 (P less than 0.01). Therefore, in our hands a specific tension value of 22.5 N X cm-2 appears to be a reasonable value for all mixed muscles studied in the guinea pig hindlimb and can be used to estimate their Po.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1715-21"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1715","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17570735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 482

Circulation and acid-base balance in exercising goats at different body temperatures. 不同体温下运动山羊的循环及酸碱平衡。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1655

G Feistkorn, A Nagel, C Jessen

{"title":"Circulation and acid-base balance in exercising goats at different body temperatures.","authors":"G Feistkorn, A Nagel, C Jessen","doi":"10.1152/jappl.1984.57.6.1655","DOIUrl":"https://doi.org/10.1152/jappl.1984.57.6.1655","url":null,"abstract":"Thirty experiments were performed in two goats at an air temperature of +35 degrees C and a relative humidity of 33%. By means of heat exchangers, body core temperature (Tpaor) was adjusted to 39, 40.5, or 42 degrees C and maintained at these levels for 120 min. During the last 60 min the animals worked at a rate of 1.2 W/kg (treadmill, 3 km/h, 15%). Blood gases (arteriovenous O2 difference, Po2, Pco2), hemoglobin (Hb), blood lactate (LA), cardiac output (CO), blood pressure (MAP), heart rate (HR), metabolic rate (M), and respiratory evaporative heat loss (REHL) were determined. M, CO, HR, and Hb increased with exercise and were independent of Tpaor. At rest and exercise, REHL increased and Pco2 decreased at higher levels of Tpaor resulting in a respiratory alkalosis. During exercise this was accompanied by an increase in LA. At all instants, the concentrations of LA were higher at higher Tpaor. It is concluded that in a virtually nonsweating species like the goat the overall stress on the circulatory system caused by hyperthermia during exercise is relatively small while the behavior of blood LA is indicative of a temperature-dependent accumulation of LA also in the exercising muscle.","PeriodicalId":15258,"journal":{"name":"Journal of applied physiology: respiratory, environmental and exercise physiology","volume":"57 6","pages":"1655-61"},"PeriodicalIF":0.0,"publicationDate":"1984-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1152/jappl.1984.57.6.1655","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17497730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Hemodynamic and metabolic effects of exercise in Crotalaria-induced pulmonary hypertension in rats. 运动对大鼠肺动脉高压血流动力学和代谢的影响。

Journal of applied physiology: respiratory, environmental and exercise physiology Pub Date : 1984-12-01 DOI: 10.1152/jappl.1984.57.6.1829

L J McNabb, K M Baldwin

引用次数: 7