タキキニン情報伝達と創薬の可能性

Abstract

The mammalian nervous system contains 3 main tachykinins, substance P (SP), neurokinin A (NKA), and neurokinin B (NKB), and 3 subtypes of tachykinin receptors, NK1, NK2 and NK3. There is persuasive evidence that SP and NKA act as neurotransmitters in mammalian central and peripheral nervous systems. The possibility of development of new drugs related to tachykininergic signalling will be discussed, comparing with the opioid peptide-mediated signalling. Concerning the opioid peptides, a large field of narcotic analgesics had been developed since long time ago, which was one of the hints leading to the recent discovery of opioid peptides and receptors. In contrast, tachykinins and their receptors were found recently, and attempts for the drug development are just starting. The amounts of tachykinins in mammalian CNS are comparable to those of opioid peptides, and 3 subtypes of receptors are known for both tachykinin and opioid systems, which suggests that the tachykininergic signalling in mammalian nervous system may be as important as the opiopid-mediated signalling. Therefore, we may expect that many useful drugs related to tachykinins may develop for therapeutics of pain, inflammation, central and visceral dysfunctions.