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

ABSTRACT

To compare the serum levels of inflammatory mediators in high altitude [HA] native rats, and to search for the possible underlying mechanism[s]. The 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. The study was carried out in 2 stages. In the first stage, serum levels of inflammatory markers, adhesive molecules, lipid profiles, catecholamines, magnesium [Mg[+2]], and lipid peroxidation were compared between theses 2 groups. In the second stages, inflammatory response and lipid peroxidation were analyzed in HA native rats after treatment with either alpha [Prazosin] or beta [propranolol] adrenergic blockage. The HA native rats showed significant increases in the serum levels of inflammatory cytokines, lipid profiles, as well as a significant increase in the urinary norepinephrine with a concomitant decrease in the serum levels of Mg[+2] and increased lipid peroxidation. Blockage of the beta and alpha adrenergic receptors of the HA rats caused partial or complete decreases in both inflammatory and oxidative stress mediators. Living under HA conditions results in an increased systemic inflammatory reaction; an effect that is mediated through the sympathetic nervous system mainly via alpha-adrenergic receptors and could be attributed to low Mg[+2] levels