Inhibition of adenosine accumulation into guinea pig ventricle by benzodiazepines

Several benzodiazepines were compared with dipyridamole for their ability to inhibit the nucleoside transporter specific accumulation of [3H] adenosine into guinea pig ventricle. Diazepam inhibited adenosine accumulation but was considerably less potent than dipyridamole. Lorazepam and flurazepam also inhibited accumulation, but were less potent than diazepam. Coronary vasodilation by diazepam or by dipyridamole probably is mediated via potentiation of adenosine following inhibition of the nucleoside transport system.