title: Influence of chronic aerobic exercise on microcirculatory flow and nitric oxide in humans.
abstract: In the present study we assessed the effect of physical training on Laser Doppler skin flux (LDF) and nitric oxide (NO) release, before and after 3 min of brachial artery occlusion. To this end we performed laser Doppler measurements and the venous plasma assay of nitrite/nitrate (NOx) on 10 sedentary healthy subjects and 10 endurance athletes. The sedentary control subjects had lower basal and post reperfusion levels of NOx as compared to athletes (mean +/- SE: 27.8 +/- 3.5 vs. 33.2 +/- 3.4, 48.6 +/- 7.9 vs. 60.1 +/- 10.1 micromol/L; p < 0.05). LDF at baseline was not significantly different in the two groups (157.5 +/- 7.9 and 176.64 +/- 26.7 PU for sedentary subjects and athletes, respectively) while post ischemic LDF was significantly lower in nonathletic subjects than in athletes (209.9 +/- 13 and 343.8 +/- 21.3 PU, p < 0.001). In both groups the hyperaemic stimulus significantly increased LDF and NOx levels (p < 0.01 and p < 0.05, respectively). The flow reserve, estimated as peak/basal LDF, was significantly lower in control subjects than in athletes (1.34 +/- 0.2 and 2.32 +/- 0.9, respectively, p < 0.01). In athletes, as opposed to sedentary subjects, a direct correlation was found between plasma NOx concentration and LDF both in basal conditions (r = 0.92; p < 0.001), and during hyperaemia (r = 0.84; p < 0.01). In conclusion, compared to sedentary subjects, athletes had an enhanced nitric oxide release. Hyperaemia increased LDF and nitric oxide levels both in sedentary subjects and in athletes.
authors.affiliation: CNR Institute of Clinical Physiology, Pisa, Italy. cristina.vassalle@ifc.cnr.it
authors.forename: C
authors.initials: C
authors.lastname: Vassalle
authors.forename: V
authors.initials: V
authors.lastname: Lubrano
authors.forename: C
authors.initials: C
authors.lastname: Domenici
authors.forename: A
authors.initials: A
authors.lastname: L'Abbate
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006940:Hyperemia / Q000097:blood; D017078:Laser-Doppler Flowmetry; D008019:Life Style; D008297:Male; D008833:Microcirculation / Q000502:physiology; D009569:Nitric Oxide / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology*; D010806:Physical Education and Training / Q000379:methods; D012016:Reference Values; D012867:Skin / Q000098:blood supply*; D013177:Sports / Q000502:physiology*
chemical_list: D009569:Nitric Oxide