ADORA2A and Hypertension: Further support for this model is that inhibition of α2-AR signaling with pertussis toxin, a toxin that blocks Gi-mediated signaling [54], normalizes renovascular responses to angiotensin II in SHR kidneys and chronically reverses hypertension in SHR [55, 56], despite the fact that pertussis toxin activates renin release [57].