INVESTIGADORES
LORES ARNAIZ Silvia
congresos y reuniones científicas
Título:
Effect of endurance training on nitric oxide synthase activity and expression in human placenta.
Autor/es:
LORES ARNAIZ, S.; RAMÍREZ-VELEZ, R.; AGUILAR DE PLATA, A.C.; CZERNIZYNIEC, A.; BUSTAMANTE, J.
Lugar:
San Francisco
Reunión:
Congreso; 59th Annual Meeting and 3rd World Congress on Exercise in Medicine; 2012
Resumen:
Effect of endurance training on nitric oxide synthase activity and
expression in human placenta.
Lores Arnaiz S**, Ramírez-Vélez
R*, Aguilar de Plata AC*, Czerniczyniec A,** and Bustamante J**
*School of Medicine, University of Valle, Street 4B No. 36-00. Cali
Colombia
**Laboratory of Free Radical Biology, School of Pharmacy and
Biochemistry,
University of Buenos Aires, Junin 956, C1113AAD. Buenos Aires Argentina
Introduction: Many studies have
documented that placental development is altered by a variety of environmental
factors such as aerobic exercise training which alter placental bed blood flow
and/or oxygen delivery. The placenta lacks innervation, thus vascular tone
regulation depends on endothelial release of vasoactive molecules such as nitric
oxide (NO). Although exercise-induced increases in blood flow and in endothelial
nitric oxide synthase (eNOS) expression have been reported; it is not known if
exercise produces the same effect in human placenta.
Objectives: To determine the effects
of aerobic exercise training in the second half of pregnancy on eNOS expression
and on NO production in human placenta.
Methods: This was a randomized,
double-blinded, controlled clinical trial of 20 healthy primigravid women between
16 and 20 weeks' gestation. The training group (n=10) took part in aerobic
exercise at an intensity of 50-65% of their maximum heart rate for 60 min,
three times a week for 16 weeks. The control group (n=10) undertook their usual
physical activity. A spectrophotometric assay was used to measure NOS activity in
cytosolic samples from placental tissue and Western Blot technique was used to determine
endothelial NOS expression.
Results: The ratio eNOS/b actin expression was
4-fold increased in cytosolic samples from exercised women. A 2-fold increase
in NOS activity was observed in cytosolic samples from exercised women.
Conclusion:
Training during
pregnancy leads to an increase in eNOS expression and in total NO production in
placental cytosol. Greater eNOS expression may also underlie the
effects of exercise in the protection of gestational disorders associated to
endothelial dysfunction.Trial registration. NCT00741312.