Contribution of endogenous nitric oxide to basal vasomotor tone of peripheral vessels and plasma B-type natriuretic peptide levels in patients with congestive heart failure.
OBJECTIVE
We examined whether a relationship exists between the vasoconstrictive response to endogenous nitric oxide (NO) synthesis inhibition and the severity of heart failure in patients with congestive heart failure (CHF).


BACKGROUND
Controversy exists as to whether the vasoconstrictive response to NO synthesis inhibition in patients with CHF is comparable to that in normal subjects or is enhanced.


METHODS
Forearm blood flow (FBF) and calculated forearm vascular conductance (FVC) were obtained using plethysmography before and after administration of the NO synthesis inhibitor L-NMMA (NG-monomethyl-L-arginine) in 40 patients with CHF due to dilated cardiomyopathy and in 16 normal control subjects. Basal plasma B-type natriuretic peptide (BNP) and nitric oxide concentrations were measured in all subjects.


RESULTS
Plasma BNP and nitrite/nitrate (NOx) levels in the patients group were significantly greater and baseline FBF was significantly less. Administration of L-NMMA significantly decreased FBF and FVC in both groups. The percent changes in FBF (%FBF) and FVC (%FVC) from the baseline after L-NMMA correlated significantly with plasma BNP level (%FBF: r = 0.72; %FVC: r = 0.76; both p < 0.001). Percent changes in both FBF and FVC were greater in patients with BNP > or = 100 pg/ml than in normal subjects; however, in patients with BNP < 100 pg/ml they were comparable to those in normal subjects.


CONCLUSIONS
Vasoconstrictive response to L-NMMA in patients with CHF was preserved or enhanced in proportion to the basal plasma BNP level, indicating a close relationship between the contribution of endogenous NO to basal vasomotor tone and the severity of heart failure.
Ishibashi
Y
Y
Fourth Department of Internal Medicine, Shimane Medical University, Izumo, Japan. yuyu@shimane-med.ac.jp
Shimada
T
T
Sakane
T
T
Takahashi
N
N
Sugamori
T
T
Ohhata
S
S
Inoue
S
S
Katoh
H
H
Sano
K
K
Murakami
Y
Y
Hashimoto
M
M
D000328:Adult; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009129:Muscle Tonus / Q000187:drug effects / Q000502:physiology*; D020097:Natriuretic Peptide, Brain; D009569:Nitric Oxide / Q000502:physiology*; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D012720:Severity of Illness Index; D014666:Vasomotor System / Q000187:drug effects / Q000503:physiopathology*; D019323:omega-N-Methylarginine / Q000494:pharmacology
D004791:Enzyme Inhibitors; D020097:Natriuretic Peptide, Brain; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D009320:Atrial Natriuretic Factor