PAEONIFLORIN REVERSES GUANETHIDINE‐INDUCED HYPOTENSION VIA ACTIVATION OF CENTRAL ADENOSINE A1 RECEPTORS IN WISTAR RATS

Abstract
SUMMARY 1. Intravenous injection of paeoniflorin, a glycoside purified from the root of Paeonia lactiflora, reversed guanethidine‐induced hypotension in Wistar rats. 2. Pretreatment with the adenosine A1 receptor antagonist 8‐cyclopentyl‐1,3‐dipropylxanthine inhibited this effect of paeoniflorin in a dose‐dependent manner. 3. The action of paeoniflorin was not modified by 8‐(p‐ sulfophenyl)theophylline, the polar antagonist of the adenosine A1 receptor, which is not able to enter the central nervous system. 4. We conclude that paeoniflorin can reverse guanethidine‐induced hypotension via activation of adenosine A1 receptors in the brain of Wistar rats.