The Effects of Clonidine and Idazoxan on Cerebral Blood Flow in Rats Studied by Arterial Spin Labeling Magnetic Resonance Perfusion Imaging
Du X, Lei H
Wuhan Institute of Physics & Mathematics, Chinese Academy of Sciences
Clonidine is a widely used anti-hypertension drug. In this study, we investigated the effects of clonidine and its antagonist idazoxan on CBF in rat using MR perfusion imaging. It is shown that clonidine induces global CBF reduction in the idazoxan-naive rats, which can be reversed, in a region-dependent manner however, by the subsequent idazoxan administration. Pretreatment with idazoxan diminishes the effects of clonidine on CBF in the cortex and hypothalamus/septal region, but not in the striatum. Such observation might be related to the fact that clonidine can affect local CBF through its direct effect on central &[alpha]2-adrenergic and imidazoline receptors.