title: A3 adenosine receptor inhibition improves the efficacy of hypertonic saline resuscitation.
abstract: We reported previously that hypertonic saline (HS) treatment can prevent or upregulate the function of polymorphonuclear neutrophils (PMNs) via A2a-type adenosine receptors or A3-type adenosine receptors (A3R), respectively. A3R translocate to the cell surface upon PMN stimulation, and thus, HS promotes PMN responses under conditions of delayed HS treatment. Here we investigated if inhibition of A3R improves the protective effects of HS resuscitation in a mouse sepsis model. We found that HS nearly triples extracellular adenosine concentrations in whole blood and that inhibition of A3R with the selective antagonist MRS-1191 dose dependently improves the inhibitory effect of HS. MRS-1191 at a concentration of 1 nM enhanced the inhibitory effect of HS and reduced stimulatory effects of delayed HS treatment. Using a mouse model of cecal ligation and puncture (CLP)-induced sepsis, we found that MRS-1191 reduces acute lung injury and PMN accumulation in lung tissue. Whereas delayed HS treatment (4 mL/kg of 7.5% NaCl) of mice 1 h after CLP aggravated PMN accumulation, lung tissue damage, and mortality 24 h after CLP, infusion of MRS-1191 (2 ng/kg body weight) combined with HS reduced these detrimental effects of delayed HS treatment. Our data thus show that A3 receptor antagonists can strengthen the beneficial effects of HS resuscitation by avoiding stimulatory adverse effects that result from delayed HS administration.
authors.affiliation: Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Inoue
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sumi
authors.forename: Tobias
authors.initials: T
authors.lastname: Woehrle
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Mark I
authors.initials: MI
authors.lastname: Hirsh
authors.forename: Wolfgang G
authors.initials: WG
authors.lastname: Junger
mesh_terms: D058918:Adenosine A3 Receptor Antagonists / Q000494:pharmacology*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D004095:Dihydropyridines / Q000494:pharmacology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008168:Lung / Q000378:metabolism; D008297:Male; D051379:Mice; D020556:Neutrophil Infiltration / Q000187:drug effects; D009504:Neutrophils / Q000378:metabolism*; D043684:Receptor, Adenosine A3 / Q000378:metabolism*; D012151:Resuscitation; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*; D018805:Sepsis / Q000378:metabolism / Q000628:therapy*; D013997:Time Factors
chemical_list: D058918:Adenosine A3 Receptor Antagonists; D004095:Dihydropyridines; C107728:MRS 1191; D043684:Receptor, Adenosine A3; D012462:Saline Solution, Hypertonic