[Association of nitric oxide and eNOS with the pathogenesis of vasovagal syncope].
OBJECTIVE
To investigate the roles of nitric oxide (NO) and eNOS in the pathogenesis of vasovagal syncope (VVS).


METHODS
Fourteen children with VVS (group A), 10 children with syncope other than vasovagal (group B) and 20 healthy volunteers (group C) were enrolled. Plasma NO levels in groups A and B were determined before and at the termination of the head-up tilt table test (HUT). The G894T polymorphism within the eNOS gene was determined in the three groups.


RESULTS
Plasma NO levels in group A increased significantly when syncope attacked from 76.7+/-9.6 micromol/L (before HUT) to 90.0+/-11.4 micromol/L (P<0.05). After the syncope attack was improved, plasma NO level in group A was significantly reduced. There were no statistical differences in plasma NO levels before and after the HUT in group B. Determining the G894T polymorphism within the eNOS gene showed that group A was associated with a higher incidence of the GT gene type as compared to groups B and C (42.9% vs 10%; P<0.05).


CONCLUSIONS
Plasma NO may be involved in the pathogenesis of VVS. The increased plasma NO level may be associated with the G894T polymorphism of the eNOS gene.
Shi
Yun
Y
Children's Hospital, Fudan University, Shanghai 200032, China.
Tian
Hong
H
Gui
Yong-Hao
YH
He
Lan
L
D002648:Child; D006801:Humans; D009569:Nitric Oxide / Q000097:blood / Q000502:physiology*; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000502:physiology*; D011110:Polymorphism, Genetic; D019462:Syncope, Vasovagal / Q000209:etiology*
D009569:Nitric Oxide; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III