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Updated: Aug 2, 2026

Drug-induced Sensitization of Adenylyl Cyclase: Assay Streamlining and Miniaturization for Small Molecule and siRNA Screening Applications
Published on: January 27, 2014
Pharmacological activity of adenine dinucleotides in the periphery: possible receptor classes and transmitter
1Department of Anatomy and Developmental Biology, University College London, U.K.
Abstract:
1. The pharmacological actions of adenine dinucleotides, in particular beta-nicotinamide adenine dinucleotide (NAD), beta-nicotinamide adenine dinucleotide phosphate (NADP) and a homologous series of alpha,omega-adenine dinucleotide polyphosphates has been reviewed. 2. It is apparent that many actions of NAD can be explained in terms of activation of P1-purinoceptors, but actions of NADP cannot be explained in terms of activation of P1- or P2-purinoceptors. 3. Similarly, pharmacological activities of P1,P3-diadenosine triphosphate and P1,P4-diadenosine tetraphosphate are not in keeping with activation of P1- or P2-purinoceptors. 4. In the vas deferens and urinary bladder, P1,P4-diadenosine tetraphosphate, P1,P5-diadenosine pentaphosphate and P1,P6-diadenosine hexaphosphate act on P2x-purinoceptors and can cause desensitization of these receptors. 5. It is suggested that classes of receptors for adenine dinucleotides exist which are distinct from either P1- or P2-purinoceptors. 6. It is also suggested that in view of the finding of high concentrations of alpha,omega-adenine dinucleotide polyphosphates in adrenal medullary chromaffin cells, and of the involvement of the P2x-purinoceptor in the vas deferens and urinary bladder with purinergic neuromuscular transmission, that alpha,omega-adenine dinucleotide polyphosphates may yet be discovered in autonomic neurones and serve as neurotransmitters.
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