Adenosine is a purine nucleoside involved in many biochemical processes including energy storage, regulation of gene expression and function, and metabolism. Adenosine signals via four G protein-coupled adenosine receptors (ARs): A1AR (Adora1), A2AAR (Adora2a), A2BAR(Adora2B) and A3AR (Adora3). Generally, A1AR and A3AR are coupled to Gi, reducing cAMP and considered inhibitory. A2AAR, A2BAR are typically coupled to Gs/Gq and are stimulatory, increasing cAMP/Ca2+. Adora QKO mice are homozygous for knock-out alleles of the four adenosine receptors A1AR, A2AAR, A2BAR and A3AR. Mice are viable and fertile up to about two months, although by five months breeders produce smaller litter sizes. These mice are bred using&nbsp; females heterozygous for Adora1 and homozygous for the other 3 alleles crossed to males homozygous for all four alleles. Please note that the Adora1-/- allele is underrepresented in the progeny (as expected by Mendelian ratios). Homozygous QKO mice exhibit decreased survival starting at about 15 weeks of age (similar to the Adora1-/- mice). Mice also develop some eye infection and dermatitis (similar to the Adora2a-/- mice). &nbsp;QKO mice develop slightly lower body weight, improved glucose tolerance, lower serum free fatty acid, lower cholesterol and lower levels of insulin-like growth factor. Monocytes and polymorphonuclear leukocyte counts are reduced. Survival from surgery involving carotid ligation (an ischemic event) is reduced. Adenosine-induced hypothermia, bradycardia and hypotension is absent in Adora QKO mice. QKO mice demonstrate that adenosine receptors are not required for growth, metabolism, breeding or body temperature regulation (diurnal variation, response to stress and torpor).&nbsp;

Adora QKO mice are homozygous for knock-out alleles of the four adenosine receptors A1AR, A2AAR, A2BAR and A3AR. Adora QKO mice may be useful for studying adenosine as a signal of stress, damage, and/or danger, as well as epigenetic mechanisms of adenosine in the absence of adenosine receptors.

This strain is hosted by NIH's MMRRC, which partners with JAX for the distribution of this and other strains. For additional information and to purchase, please visit the MMRRC site.