Correlation between endothelial function measured by finger plethysmography in children and HDL-mediated eNOS activation -- a preliminary study.

BACKGROUND

The noninvasive measurement of endothelial function is a very powerful tool to assess cardiovascular disease. Especially in children this is not an easy task, and therefore an easy method like the Endo-Pat device is helpful. Due to the still existing uncertainties of the validity of endothelial measurement by the Endo-PAT device in children, we thought to analyze the correlation between endothelial functional measurement by Endo-PAT, and the capability of HDL to modify nitric oxide (NO) production by phosphorylation of endothelial nitric oxide synthase at the stimulatory site (Ser(1177)) and the inhibitory site (Thr(495)).

METHODS

The reactive hyperemic index (RHI) was measured in 11 school children by the Endo-PAT device. HDL was isolated by ultracentrifugation, and the capability to stimulate eNOS phosphorylation was assessed in cell culture.

RESULTS

A close correlation between the RHI and the eNOS-Ser(1177) phosphorylation (r=0.66, p=0.02) and the eNOS-Thr(495) phosphorylation (r=-0.60, p=0.04) was detected.

CONCLUSION

The results obtained in our limited study performed in healthy children supports the validity of endothelial function measurement in children using the Endo-PAT device. Nevertheless, studies measuring FMD and the RHI index need to confirm the strength of the Endo-Pat device also in children.