Artículo de revista
Fetal and postnatal pulmonary circulation in the Alto Andino
Fecha
2011Registro en:
Placenta 32, Supplement B, Trophoblast Research, Vol. 25 (2011) S100-S103
doi:10.1016/j.placenta.2011.01.001
Autor
Llanos Mansilla, Jorge
Ebensperger Darrouy, Germán
Herrera Videla, Emilio
Reyes, R. V.
Pulgar, V. M.
Serón Ferré, María
Díaz Beneventi, Mauricio
Parer, J. T.
Giussani, Dino A.
Moraga, F. A.
Riquelme González, Raquel
Institución
Resumen
Lowland mammals at high altitude constrict the pulmonary vessels, augmenting vascular resistance and
developing pulmonary arterial hypertension. In contrast, highland mammals, like the llama, do not
present pulmonary arterial hypertension. Using wire myography, we studied the sensitivity to norepinephrine
(NE) and NO of small pulmonary arteries of fetal llamas and sheep at high altitudes. The
sensitivity of the contractile responses to NE was decreased whereas the relaxation sensitivity to NO was
augmented in the llama fetus compared to the sheep fetus. Altogether these data show that the fetal
llama has a lower sensitivity to a vasoconstrictor (NE) and a higher sensitivity to a vasodilator (NO), than
the fetal sheep, consistent with a lower pulmonary arterial pressure found in the neonatal llama in the
Andean altiplano. Additionally, we investigated carbon monoxide (CO) in the pulmonary circulation in
lowland and highland newborn sheep and llamas. Pulmonary arterial pressure was augmented in
neonatal sheep but not in llamas. These sheep had reduced soluble guanylate cyclase and heme oxygenase
expression and CO production than at lowland. In contrast, neonatal llamas increased markedly
pulmonary CO production and HO expression at high altitude. Thus, enhanced pulmonary CO protects
against pulmonary hypertension in the highland neonate. Further, we compared pulmonary vascular
responses to acute hypoxia in the adult llama versus the adult sheep. The rise in pulmonary arterial
pressure was more marked in the sheep than in the llama. The llama pulmonary dilator strategy may
provide insights into new treatments for pulmonary arterial hypertension of the neonate and adult.