Type:

Other

Description:

Danshen, a Chinese herb, reduces hypertension in Oriental medicine. We hypothesized that Danshen acts partially through endothelial nitric oxide synthase (eNOS) signaling mechanisms. We tested the hypothesis using tanshinone IIA, an active ingredient of Danshen, and the two-kidney, one-clip renovascular hypertension model in hamsters. Oral tanshinone (50 µg/100 g body wt) reduced mean arterial pressure (MAP) from 161.2 ± 6.9 to 130.0 ± 7.8 mmHg (mean ± SE; P < 0.05) in hypertensive hamsters. MAP in sham-operated hamsters was 114.3 ± 9.2 mmHg. Topical tanshinone at 1 µg/ml and 5 µg/ml increased normalized arteriolar diameter from 1.00 to 1.25 ± 0.08 and 1.57 ± 0.11, respectively, and increased periarteriolar nitric oxide concentration from 87.1 ± 11.3 to 146.9 ± 23.1 nM (P < 0.05) at 5 µg/ml in hamster cheek pouch. NG-monomethyl-L-arginine inhibited tanshinone-induced vasodilation. Hypertension reduced eNOS protein relative to sham-operated control. Tanshinone prevented the hypertension-induced reduction of eNOS and increased eNOS expression to levels higher than sham-operated control in hamster cheek pouch. Topical tanshinone increased normalized arteriolar diameter from 1.0 to 1.47 ± 0.08 in the cremaster muscle of control mice and to 1.12 ± 0.13 in cremasters of eNOS knockout mice. In ECV-304 cells transfected with eNOS-green fluorescent protein, tanshinone increased eNOS protein expression 1.35 ± 0.05- and 1.85 ± 0.07-fold above control after 5-min and 1-h application, respectively. Tanshinone also increased eNOS phosphorylation 1.19 ± 0.07- and 1.72 ± 0.20-fold relative to control after 5-min and 1-h application. Our data provide a basis to understand the action of a Chinese herb used in alternative medicine. We conclude that eNOS stimulation is one mechanism by which tanshinone induces vasodilation and reduces blood pressure.

Subjects:

  • Education > General

Education Levels:

    Keywords:

    Tutorial or self-directed instruction,NSDL,NSDL_SetSpec_BEN,Education,Hypertension,Life Science,Teacher-centered/traditional instruction,oai:nsdl.org:2200/20090420201222001T,Student-centered instruction

    Language:

    English

    Access Privileges:

    Public - Available to anyone

    License Deed:

    Creative Commons Attribution Non-Commercial Share Alike

    Collections:

    None
    This resource has not yet been aligned.
    Curriki Rating
    'NR' - This resource has not been rated
    NR
    'NR' - This resource has not been rated

    This resource has not yet been reviewed.

    Not Rated Yet.

    Non-profit Tax ID # 203478467