title: Skeletal muscle metaboreflex in patients with chronic renal failure.
abstract: The sympathetic nervous system is affected in patients with chronic renal failure (CRF). This study tested the hypothesis that patients with CRF have an altered skeletal muscle metaboreflex. Twenty patients with CRF and 18 healthy subjects of similar age participated in the study. The muscle metaboreflex was determined based on heart rate (HR), mean arterial pressure, calf blood flow and calf vascular resistance (CVR) in response to handgrip exercise. The control of vascular resistance in the calf muscle mediated by the metaboreflex was estimated by subtracting the area under the curve with circulatory occlusion from that without occlusion. Arterial pressure and HR responses during exercise and recovery were similar in two groups of subjects. In the control group, CVR increased during exercise and remained elevated during circulatory occlusion, whereas no significant change was seen in the patients. Thus, the index of the metaboreflex was 7·82 ± 9·57 in the patients versus16·52 ± 14 units in the controls. The findings demonstrate that patients with CRF have a decreased vascular resistance response in the calf during the handgrip exercise, which suggests that CRF condition attenuates this reflex.
authors: Exercise Pathophysiology Research Laboratory, Hospital de Clinicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors: Paulo J C
authors: PJ
authors: Vieira
authors: Physical Therapy Division, Serra Gaucha College and Public Health Research Group, Caxias do Sul, Brazil.
authors: Leonardo R
authors: LR
authors: Silva
authors: Physical Therapy Department, University of Brasilia, Brasilia, Brazil.
authors: Vinicius Z
authors: VZ
authors: Maldamer
authors: Physical Therapy Department, University of Brasilia, Brasilia, Brazil.
authors: Gerson
authors: G
authors: Cipriano
authors: Physical Therapy Service, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil.
authors: Adriana M G
authors: AM
authors: Chiappa
authors: Physical Therapy Division, Serra Gaucha College and Public Health Research Group, Caxias do Sul, Brazil.
authors: Rodrigo
authors: R
authors: Schuster
authors: Biomedicine Division, Serra Gaucha College, Caxias do Sul, Brazil.
authors: Victor H F
authors: VH
authors: Boni
authors: Physical Therapy Division, Serra Gaucha College and Public Health Research Group, Caxias do Sul, Brazil.
authors: Tatiani
authors: T
authors: Grandi
authors: Physical Therapy Division, Serra Gaucha College and Public Health Research Group, Caxias do Sul, Brazil.
authors: Andiara
authors: A
authors: Wolpat
authors: Exercise Pathophysiology Research Laboratory, Hospital de Clinicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors: Bruno T
authors: BT
authors: Roseguini
authors: Exercise Pathophysiology Research Laboratory, Hospital de Clinicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors: Gaspar R
authors: GR
authors: Chiappa
mesh_terms: D000328:Adult; D062186:Arterial Pressure; D016022:Case-Control Studies; D015444:Exercise; D005080:Exercise Test; D018737:Hand Strength; D006339:Heart Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology*; D007866:Leg; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000294:innervation* / Q000378:metabolism; D020127:Recovery of Function; D012021:Reflex, Abnormal; D013997:Time Factors; D014655:Vascular Resistance
keywords: autonomic nervous system; blood flow; static exercise; sympathetic activity; vasoconstriction