Stereospecific binding sites for [3H]nicotinamide adenine dinucleotide in the rat brain

NAD is a potent inhibitor of electrical activity in the dentate gyrus of the guinea pig hippocampus. NAD is rapidly degraded by an NADase enzyme present on synaptosomal membranes that we have recently found to be inhibited by nicotinamide mononucleotide. In this report we have characterised the binding sites present on brain membranes for [3H]NAD in the presence of this inhibitor. We have demonstrated two binding sites of KdS 49 nM and 4.26 …