title: Exercise training alters the balance between vasoactive compounds in skeletal muscle of individuals with essential hypertension.
abstract: The effects of physical training on the formation of vasodilating and vasoconstricting compounds, as well as on related proteins important for vascular function, were examined in skeletal muscle of individuals with essential hypertension (n=10). Muscle microdialysis samples were obtained from subjects with hypertension before and after 16 weeks of physical training. Muscle dialysates were analyzed for thromboxane A(2), prostacyclin, nucleotides, and nitrite/nitrate. Protein levels of thromboxane synthase, prostacyclin synthase, cyclooxygenase 1 and 2, endothelial nitric oxide synthase (eNOS), cystathionine-γ-lyase, cytochrome P450 4A and 2C9, and the purinergic receptors P2X1 and P2Y2 were determined in skeletal muscle. The protein levels were compared with those of normotensive control subjects (n=12). Resting muscle dialysate thromboxane A(2) and prostacyclin concentrations were lower (P<0.05) after training compared with before training. Before training, dialysate thromboxane A(2) decreased with acute exercise, whereas after training, no changes were found. Before training, dialysate prostacyclin levels did not increase with acute exercise, whereas after training there was an 82% (P<0.05) increase from rest to exercise. The exercise-induced increase in ATP and ADP was markedly reduced after training (P<0.05). The amount of eNOS protein in the hypertensive subjects was 40% lower (P<0.05) than in the normotensive control subjects, whereas cystathionine-γ-lyase levels were 25% higher (P<0.05), potentially compensating for the lower eNOS level. We conclude that exercise training alters the balance between vasodilating and vasoconstricting compounds as evidenced by a decrease in the level of thromboxane, reduction in the exercise-induced increase in ATP and a greater exercise-induced increase in prostacyclin.
authors: Copenhagen Muscle Research Centre, University of Copenhagen, Department of Exercise and Sports Sciences, Universitetsparken 13, DK-2100 Copenhagen Ø, Denmark.
authors: Ane H
authors: AH
authors: Hansen
authors: Michael
authors: M
authors: Nyberg
authors: Jens
authors: J
authors: Bangsbo
authors: Bengt
authors: B
authors: Saltin
authors: Ylva
authors: Y
authors: Hellsten
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood* / Q000378:metabolism; D001795:Blood Pressure Determination; D015153:Blotting, Western; D016022:Case-Control Studies; D011464:Epoprostenol / Q000378:metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D006973:Hypertension / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*; D010806:Physical Education and Training / Q000379:methods*; D012016:Reference Values; D013931:Thromboxanes / Q000378:metabolism
chemical_list: D015415:Biomarkers; D013931:Thromboxanes; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D011464:Epoprostenol