Increased systemic low-grade infammation in high altitude native rats mediated by adrenergic receptors

Objectives: To compare the serum levels of infammatory mediators in high altitude (HA) native rats, and to search for the possible underlying mechanism(s). Methods: Te study was carried out between January and April 2013. Fifty male rats from the same genetic pool were bred at either a HA or low altitude (LA) area. Te study was carried out in 2 stages. In the first stage, serum levels of infammatory markers, adhesive molecules, lipid profles, catecholamines, magnesium (Mg⁺²), and lipid peroxidation were compared between theses 2 groups. In the second stages, infammatory response and lipid peroxidation were analyzed in HA native rats after treatment with either α (Prazosin) or ß (propranolol) adrenergic blockage. Results: Te HA native rats showed signifcant increases in the serum levels of infammatory cytokines, lipid profles, as well as a signifcant increase in the urinary norepinephrine with a concomitant decrease in the serum levels of Mg⁺² and increased lipid peroxidation. Blockage of the ß and α adrenergic receptors of the HA rats caused partial or complete decreases in both infammatory and oxidative stress mediators. Conclusion: Living under HA conditions results in an increased systemic infammatory reaction; an effect that is mediated through the sympathetic nervous system mainly via α-adrenergic receptors and could be attributed to low Mg⁺² levels.