title: Comparison of arterial occlusion and ischaemic exercise for the study of vasodilatation in the human calf.
abstract: 1. Calf blood flow was measured by venous occlusion plethysmography to compare two stimuli for eliciting maximal calf vascular conductance: (i) 10 min of arterial occlusion and (ii) isolated exhaustive calf exercise with ischaemic occlusion. The subjects were semi-supine with the calf in position for immediate blood flow measurements after release of the occluding cuff. Three groups of subjects were studied: young [35 years (SD 9, n = 9)], old [57 years (SD 5, n = 10)] and patients with congestive heart failure [63 years (SD 7, n = 7)]. 2. Occlusion and ischaemic exercise were equally effective in producing maximal calf vascular conductance in each of the subject groups. Maximal calf vascular conductance (ml min-1 100 ml-1 mmHg-1) was equivalent in the young [ischaemic exercise 0.54 (SEM 0.03), occlusion 0.54 (SEM 0.05)] and old [ischaemic exercise 0.47 (SEM 0.05), occlusion 0.48 (SEM 0.04)] subjects. However, patients with congestive heart failure exhibited significantly reduced maximal calf vascular conductance [ischaemic exercise 0.20 (SEM 0.02), occlusion 0.20 (SEM 0.01)]. 3. Analysis of the curves, generated by plotting serial calf vascular conductance values obtained immediately and every 15 s after occlusion cuff release for 165 s, revealed differences in the pattern of vasodilatation after occlusion and ischaemic exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, University of Wisconsin Medical School, Madison 53792-3248, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Rueckert
authors.forename: P
authors.initials: P
authors.lastname: Hanson
mesh_terms: D000328:Adult; D005080:Exercise Test; D005260:Female; D006333:Heart Failure / Q000503:physiopathology; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D010991:Plethysmography; D012039:Regional Blood Flow / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology; D014664:Vasodilation