Enhanced Vasoconstriction Mediated by α₁-Adrenergic Mechanisms in Small Femoral Arteries in Newborn Llama and Sheep Gestated at Low and High Altitudes.

ABSTRACT: The authors previously demonstrated that newborn llama (NBLL) express high levels of α₁ adrenergic receptors, which provide a potent vasoconstriction response when compared with newborn sheep (NBSH) gestated at sea level. However, data regarding the impact of chronic gestational hypobaric hypoxia on α-adrenergic vasoconstriction in the neonatal life has not been studied. We evaluated if gestation under chronic hypobaric hypoxia modifies α₁-adrenergic vasoconstrictor function in NBLL and NBSH. We compared the vasoconstrictor response induced by potassium and α-adrenergic stimuli in isolated small femoral arteries of NBLL and NBSH gestated at high altitude (HA; 3,600 m) or low altitude (LA; 580 m). The maximal contraction (R _MAX) and potency (EC₅₀

SUBMITTER: Moraga FA 

PROVIDER: S-EPMC8371382 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature