peoniflorin and Hypotension

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.

Topics: Adrenergic Agents; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoates; Blood Pressure; Bridged-Ring Compounds; Dose-Response Relationship, Drug; Glucosides; Guanethidine; Hypotension; Male; Monoterpenes; Plants, Medicinal; Purinergic P1 Receptor Antagonists; Rats; Rats, Wistar; Receptors, Purinergic P1; Xanthines