Clinical physiology (Oxford, England)最新文献_第2页

The separate and combined effect of leucine and insulin on muscle free amino acids. 亮氨酸和胰岛素对肌肉游离氨基酸的单独和联合作用。

Clinical physiology (Oxford, England) Pub Date : 1994-09-01 DOI: 10.1111/j.1475-097x.1994.tb00410.x

P Essén, S D Heys, P Garlick, J Wernerman

{"title":"The separate and combined effect of leucine and insulin on muscle free amino acids.","authors":"P Essén, S D Heys, P Garlick, J Wernerman","doi":"10.1111/j.1475-097x.1994.tb00410.x","DOIUrl":"https://doi.org/10.1111/j.1475-097x.1994.tb00410.x","url":null,"abstract":"The effect of insulin and leucine on amino acid and protein metabolism in muscle is not fully understood. To characterize their separate and combined effects on free amino acids in muscle and plasma, 11 volunteers received an infusion of either leucine (1 g h-1, Group 1) or glucose (20 g h-1, Group 2) for 2 h followed by a combination of the two infusions for an additional 2-h period. In muscle both the leucine infusion and the leucine plus glucose infusion increased the concentration of free leucine significantly, while the sum of the other branched chain amino acids (BCAA), of the aromatic amino acids and of the basic amino acids decreased. Glucose infusion alone decreased the sum of the essential amino acids, the BCAA and the aromatic amino acids. The combination of leucine and glucose augmented the decreases, while the concentrations of glutamate, glutamine and alanine were unaffected. In plasma the leucine infusion doubled the leucine concentration and decreased alanine, valine, methionine, tyrosine, phenylalanine and the sum of the aromatic amino acids. Glucose infusion decreased methionine, serine, isoleucine and the sum of the essential amino acids and of the BCAA. The combination of leucine infusion and hyperinsulinaemia augmented the decreases. The plasma concentrations of the keto acids of valine and isoleucine decreased by the leucine infusion while the concentrations of the keto acid of leucine and isoleucine decreased by glucose infusion. The combination of leucine and glucose had an additive effect. These effects are attributed to a specific effect of leucine on the other two BCAA and a depression of muscle proteolysis by both leucine and insulin, resulting from glucose infusion.","PeriodicalId":77071,"journal":{"name":"Clinical physiology (Oxford, England)","volume":"14 5","pages":"513-25"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1475-097x.1994.tb00410.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18819661","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: 9

Noninvasive study of left ventricular function and systemic haemodynamics during dipyridamole echocardiography stress test. 双嘧达莫超声心动图负荷试验中左心室功能和全身血流动力学的无创研究。

Clinical physiology (Oxford, England) Pub Date : 1994-09-01 DOI: 10.1111/j.1475-097x.1994.tb00416.x

S Aakhus, K Bjørnstad, L Hatle

{"title":"Noninvasive study of left ventricular function and systemic haemodynamics during dipyridamole echocardiography stress test.","authors":"S Aakhus, K Bjørnstad, L Hatle","doi":"10.1111/j.1475-097x.1994.tb00416.x","DOIUrl":"https://doi.org/10.1111/j.1475-097x.1994.tb00416.x","url":null,"abstract":"Left ventricular function and systemic haemodynamics were noninvasively assessed during cardiac stress testing with dipyridamole (0.84 mg kg-1 i.v.) in 10 subjects (44-61 years) with normal coronary arteries (group 1), and in 14 patients (46-77 years) with coronary artery disease either without (group 2, n = 6) or with (group 3, n = 8) echocardiographic evidence for myocardial ischaemia during test. Left ventricular wall motion and dimensions, and aortic root pressure and flow were obtained by Doppler echocardiography combined with an externally traced subclavian artery pulse calibrated with brachial artery pressures. Peripheral arterial resistance, total arterial compliance, and aortic characteristic impedance were estimated from aortic root pressure and flow, by use of a three-element windkessel model of the systemic circulation. Left ventricular ejection fraction improved from baseline to peak stress in group 1 (mean +/- SD: 62 +/- 6% vs. 65 +/- 6%, P = 0.05), whereas it was not significantly changed in group 2 (58 +/- 10% vs. 56 +/- 6%) and decreased in group 3 (53 +/- 10% vs. 43 +/- 10%, P < 0.05). Otherwise, the haemodynamic response was similar in the three groups: heart rate and cardiac index increased by at least 30% and 37%, respectively, whereas stroke index and arterial pressures were maintained at or slightly above baseline. Peripheral resistance decreased by at least 22%, and total arterial compliance and aortic characteristic impedance were not significantly altered during test. The worsening of wall motion abnormality at peak stress in group 3 was not significantly related to the change in systemic haemodynamics. Thus, dipyridamole acted predominantly on the arterioles without significantly influencing the large systemic arteries. Myocardial ischaemia during test impaired regional and global left ventricular function, but did not influence the systemic haemodynamic response.","PeriodicalId":77071,"journal":{"name":"Clinical physiology (Oxford, England)","volume":"14 5","pages":"581-94"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1475-097x.1994.tb00416.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18822901","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: 9

Growth hormone suppression and glutamine flux associated with cardiac surgery. 生长激素抑制和谷氨酰胺通量与心脏手术相关。

Clinical physiology (Oxford, England) Pub Date : 1994-09-01 DOI: 10.1111/j.1475-097x.1994.tb00415.x

H Powell, L M Castell, M Parry-Billings, J P Desborough, G M Hall, E A Newsholme

{"title":"Growth hormone suppression and glutamine flux associated with cardiac surgery.","authors":"H Powell, L M Castell, M Parry-Billings, J P Desborough, G M Hall, E A Newsholme","doi":"10.1111/j.1475-097x.1994.tb00415.x","DOIUrl":"https://doi.org/10.1111/j.1475-097x.1994.tb00415.x","url":null,"abstract":"Pharmacological doses of growth hormone (GH) in humans and rats increase plasma and muscle glutamine values. As major surgery results in a physiological rise in serum GH concentration, we investigated whether this physiological increase in GH altered glutamine metabolism. Eighteen patients undergoing coronary artery bypass graft (CABG) surgery were randomly assigned to receive somatostatin, 100 micrograms subcutaneously at induction of anaesthesia and 8 hourly for 48 h, or placebo. Somatostatin effectively blocked the physiological surge of GH following injury but did not affect plasma or muscle glutamine concentrations, which fell significantly in both groups. Plasma glutamine decreased by 31% (P < 0.01) and 28% (P < 0.01) in the control and somatostatin groups respectively. Muscle glutamine was reduced 45% (P < 0.001) in the control group and 50% (P < 0.001) in the somatostatin group. There was no difference in muscle or circulating glutamate, alanine or branched chain amino acid concentrations or in metabolite values between the somatostatin-treated patients and the control group. There was no relationship between the GH response to surgery and glutamine metabolism following major surgery.","PeriodicalId":77071,"journal":{"name":"Clinical physiology (Oxford, England)","volume":"14 5","pages":"569-80"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1475-097x.1994.tb00415.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18822900","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: 23

Cerebral vasodilation capacity: acute intracranial hypertension and supra- and infra-tentorial artery velocity recording. 脑血管舒张能力:急性颅内高压和幕上、幕下动脉速度记录。

Clinical physiology (Oxford, England) Pub Date : 1994-09-01 DOI: 10.1111/j.1475-097x.1994.tb00409.x

J M de Bray, F Tranquart, J L Saumet, M Berson, L Pourcelot

{"title":"Cerebral vasodilation capacity: acute intracranial hypertension and supra- and infra-tentorial artery velocity recording.","authors":"J M de Bray, F Tranquart, J L Saumet, M Berson, L Pourcelot","doi":"10.1111/j.1475-097x.1994.tb00409.x","DOIUrl":"https://doi.org/10.1111/j.1475-097x.1994.tb00409.x","url":null,"abstract":"This experiment is the first to compare cerebral vasomotor reactivity in the supra- and infra-tentorial regions in baseline conditions and during progressive acute intracranial hypertension. The increase in intracranial pressure was performed using liquid pressure transmission in two groups of 16 rabbits by elevating a saline infusion bottle connected to the subdural space. Cerebral microvessel dilation capacity was studied using acetazolamide arterial infusion during three stages of 20 min: at baseline conditions, with an intracranial pressure value equal to half the diastolic arterial pressure and with an intracranial pressure equal to the diastolic arterial pressure. The effects of acetazolamide in the basilar artery and in the carotid siphon were simultaneously monitored by transcranial Doppler sonography during all the experiments. The changes in cerebral vasomotor reactivity occurred with the same intensity and latency in both vascular compartments in baseline conditions. The maximum amplitude of changes happened 30 s later in the basilar artery than in the carotid siphon. When intracranial pressure was above half the diastolic arterial pressure, the vasomotor tone began to decrease in the carotid siphon which supplies a small region of the rabbit brain, whereas it was maintained in the basilar artery. This effect could be explained by brain tissue hypertension. Vasomotor reactivity had nearly disappeared in all the cerebral arteries investigated when intracranial hypertension was equal to the diastolic arterial pressure. These results show evidence of a direct and late effect of acute elevation of intracranial pressure on cerebral microvascular tone. This begins in the supra-tentorial region but there is an early local effect on the carotid siphon due to the brain tissue pressure.","PeriodicalId":77071,"journal":{"name":"Clinical physiology (Oxford, England)","volume":"14 5","pages":"501-12"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1475-097x.1994.tb00409.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18819660","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

Effect of propofol and thiopentone on regional blood flow in brain and peripheral tissues during normoxia and hypoxia in the dog. 异丙酚和硫喷妥酮对狗常氧和缺氧时脑和外周组织局部血流量的影响。

Clinical physiology (Oxford, England) Pub Date : 1993-12-01 DOI: 10.1097/00132586-199312000-00007

J. Haberer, G. Audibert, C. Saunier, C. Muller, M. Laxenaire, D. Hartemann

{"title":"Effect of propofol and thiopentone on regional blood flow in brain and peripheral tissues during normoxia and hypoxia in the dog.","authors":"J. Haberer, G. Audibert, C. Saunier, C. Muller, M. Laxenaire, D. Hartemann","doi":"10.1097/00132586-199312000-00007","DOIUrl":"https://doi.org/10.1097/00132586-199312000-00007","url":null,"abstract":"The effect of propofol and thiopentone on cerebral (CBF), myocardial (MBF), muscular, and arterial hepatic blood flow was assessed with radiolabelled microspheres in 12 chronically instrumented dogs, six given propofol and six thiopentone. Tissue blood flows were measured in the awake animal, after 30 min of normoxic anaesthesia (room air), and after 30 min of hypoxic anaesthesia using a mixture of 10% O2 and 3% CO2 in nitrogen. The decrease in CBF from awake to normoxic anaesthesia was similar with propofol and thiopentone (propofol: 77 +/- 8 to 38 +/- 3 ml min-1 100 g-1, P < 0.01; thiopentone: 66 +/- 3 to 33 +/- 2 ml min-1 100 g-1, P < 0.01). During hypoxia, CBF rose moderately in the two groups (respectively +19% and +28%, P < 0.05). The MBF increased in propofol and thiopentone groups after 30 min of anaesthesia with air (propofol: 97 +/- 23 to 137 +/- 15 ml min-1 100 g-1; thiopentone: 82 +/- 7 to 141 +/- 10 ml min-1 100 g-1) and increased still more during hypoxia. The increase in MBF was related to an increase in heart rate and blood pressure. The quadriceps blood flow decreased during anaesthesia in normoxia and in hypoxia. The diaphragmatic blood flow increased with thiopentone under hypoxia. The hepatic arterial blood flow was unchanged. It is concluded that the effects of propofol on regional blood flows are very similar to those of thiopentone.","PeriodicalId":77071,"journal":{"name":"Clinical physiology (Oxford, England)","volume":"1 1","pages":"197-207"},"PeriodicalIF":0.0,"publicationDate":"1993-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1097/00132586-199312000-00007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61642145","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: 17

8th Scandinavian Congress of Clinical Physiology. 14-15 June 1989, Helsinki, Sweden. Proceedings. 第八届斯堪的纳维亚临床生理学大会，1989年6月14-15日，赫尔辛基，瑞典。程序。

Clinical physiology (Oxford, England) Pub Date : 1990-05-01