... decline cannot be ascribed to failure of the baroreflex-buffering capacity with increasing age. Age-related differences in the laboratory presentation of a vasovagal episode depend on the magnitude of the underlying bradycardic response. age baroreflex sensitivity blood pressure head-up tilt...

... with muscle tensing during 70° head-up tilt. Healthy subjects ( n =13) were monitored for 10 min in the supine position followed by 10 min in 70° head-up tilt and, finally, for 2 min of leg crossing with muscle tensing in 70° head-up tilt. MAP (mean arterial BP), heart rate, stroke volume, cardiac output...

... of carotid baroreceptors by application of pressures of -30 and +30mmHg to a chamber fitted over the neck. Responses were determined after 20min of supine rest and after 10min of head-up tilt at 60°. Responses of cardiac interval were not significantly different between the three groups, and they were...

... contribute to nocturnal postural hypotension in the elderly. We therefore studied haemodynamic responses to head-up tilt in healthy elderly and young subjects, with and without passive heating induced by covering with blankets. 2. Nine young (28.7 ± 1.5 years; mean ± S.E.M.) and nine elderly (71.9 ± 1.8...

...Erling Bo Andersen; Finn Boesen; Ole Henriksen; Michael Sonne 1. Relative changes in blood flow and vascular resistance in arm and leg muscle during head-up tilt at 45° were studied in eight patients with complete cervical spinal cord transection and in 13 healthy volunteers. 2. Muscle blood flow...

...C. Borst; J. F. M. Van Brederode; W. Wieling; G. A. Van Montfrans; A. J. Dunning 1. The influence of supine rest on the blood pressure response to standing and 70° head-up tilt was studied in detail for the first 30 s after the change of posture. 2. Following 20 min of supine rest, the active...

... not affected in the acute phase of myocardial infarction. 5. Passive head-up tilt (30°) induced vasoconstriction in skeletal muscle tissue. There were no differences in this response at any time during the course of acute myocardial infarction. 6. The abolition of the vasoconstrictor response to increase...

...K. Skagen; K. Jensen; O. Henriksen; L. Knudsen 1. The effect of head-up tilt upon subcutaneous blood flow in the distal arm and leg was studied in 12 patients with complete traumatic spinal cord transection at the cervical level. 2. Blood flow was measured by the local 133 Xe washout technique. 3...

...B. Ricciardelli; M. Volpe; B. Trimarco; M. Chiariello; F. Rengo; Mario Condorelli 1. The reflex control of arginine-vasopressin release was studied in 12 essential established hypertensive patients and in 12 age-matched normal subjects by comparing the effects of head-up tilt and a variable...

... on day 1 after coronary occlusion but gradually recurred during days 2, 3 and 7. 4. Passive 30° head-up tilt induced a vasoconstriction in subcutaneous tissue. There was no difference in this response at any time during the course of acute myocardial infarction. The vasoconstriction could be blocked...

..., renin activity, aldosterone, cortisol and serum potassium in 15 sodium-repleted hypertensive patients in supine position and during 30 min of 65° head-up tilt before and during treatment with SQ 14 225. 2. SQ 14 225 produced significant decreases in supine blood pressure and plasma aldosterone...

...M. D. Esler; P. J. Nestel 1. The effect of 25° head-up tilt on blood pressure, urinary catecholamines, and creatinine clearance has been studied in untreated essential hypertensive patients and normotensive subjects. 2. The mean rise in diastolic pressure for all subjects with hypertension was 4.9...