Format

Send to

Choose Destination
See comment in PubMed Commons below
Microcirculation. 2002 Apr;9(2):91-7.

Decreased arteriolar sensitivity to shear stress in adult rats is reversed by chronic exercise activity.

Author information

1
Department of Physiology, New York Medical College, Valhalla, NY 10595, USA. Dong_Sun@nymc.edu

Abstract

OBJECTIVE:

We tested the hypothesis that the decline in endothelium-dependent arteriolar dilation in adult rats is reversed by chronic exercise activity.

METHODS:

Rats were divided into young (8-10 weeks)-sedentary (SED(Y)), adult (29-32 weeks)-sedentary (SED(A)), and adult-exercised (EX(A), treadmill exercise for 18-20 weeks) groups. Responses of isolated arterioles ( approximately 50 microm at 80 mm Hg) of gracilis muscle were assessed to increases in perfusate flow and vasoactive agents.

RESULTS:

With no differences in basal tone, maximal flow-induced dilations were not different between arterioles of SED(Y) and SED(A) rats (71 +/- 2 and 72 +/- 2% of passive diameter, respectively), yet the sensitivity of arterioles to shear stress (WSS(50)) was significantly less in SED(A) than in SED(Y) rats (35 +/- 4 vs. 23 +/- 3 dyne/cm(2), respectively). In vessels of EX(A) rats, maximal flow-induced dilation was significantly augmented (88 +/- 2% of passive diameter) and WSS(50) (15 +/- 1 dyn/cm(2)) was significantly reduced. Dilation to acetylcholine was enhanced in arterioles of EX(A), whereas dilation to sodium nitroprusside was not different in vessels of the three groups.

CONCLUSION:

Chronic exercise activity reverses age related reduction in sensitivity of arterioles to increases in wall shear stress.

PMID:
11932776
DOI:
10.1038/sj/mn/7800124
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center