Microvascular reactivity in lean, overweight, and obese hypertensive adolescents.
The microvascular responses to endothelium-dependent vasodilators (e.g., acetylcholine), endothelium-independent vasodilators (e.g., sodium nitroprusside), and to local heating were studied (for the first time) in adolescents with essential hypertension, grouped according to their body mass index. The forearm microvascular reactivities of thirty-three hypertensive adolescents (ten lean, 13 overweight, and ten obese) and 19 healthy controls were assessed by means of laser Doppler flowmetry. Blood levels of enzymatic and nonenzymatic antioxidants and malondialdehyde were determined. The perfusion increments in response to acetylcholine iontophoresis were not significantly attenuated in the patient groups as compared with the controls. Sodium nitroprusside (SNP) iontophoresis resulted in significantly smaller perfusion increments in the lean and obese hypertensives than in the controls (both p < 0.05). Similar responses to local heating (44°C) performed after either acetylcholine or SNP iontophoresis were observed at the respective measurement sites. As compared with the controls, we found elevated ratios of the whole blood oxidized and reduced glutathione in all the patient groups (all p < 0.001), increased erythrocyte catalase activities in the overweight hypertensives (p < 0.05), and decreased ratios of the plasma alpha-tocopherol and triglycerides in the obese hypertensive group (p < 0.05).


CONCLUSIONS
The endothelium-dependent microvascular reactivity was not significantly attenuated in the hypertensive adolescents in contrast with the impaired endothelium-independent vasorelaxation in the lean and obese hypertensives.
Monostori
Péter
P
Department of Paediatrics, University of Szeged, Korányi fasor 14-15, Szeged, Hungary. monostoripeter@gmail.com
Baráth
Akos
A
Fazekas
Ildikó
I
Hódi
Eszter
E
Máté
Adrienn
A
Farkas
Ildikó
I
Hracskó
Zsuzsanna
Z
Varga
Ilona S
IS
Sümegi
Viktória
V
Gellén
Balázs
B
Bereczki
Csaba
C
Túri
Sándor
S
D000293:Adolescent; D001794:Blood Pressure; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D017078:Laser-Doppler Flowmetry; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008833:Microcirculation / Q000502:physiology*; D009765:Obesity / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D050177:Overweight / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D018384:Oxidative Stress; D011379:Prognosis; D012307:Risk Factors; D013851:Thinness / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult
D008315:Malondialdehyde