|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1994 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1993 : ¥1,000,000 (Direct Cost : ¥1,000,000)
1)Intrathecal (i.t.) injection of substance P (SP) in mice produced a series of scratching, bitting and licking (SBL) behavioral response.
2)I.t.injection of SP (1-7), an N-terminal SP fragment, reduced SP-induced SBL response.
3)Similar effects were observed by SP (1-7) analogues, [D-Arg^1]SP (1-7), [D-Arg^1, D-Pr^2] SP (1-7), [D-Arg^1, D-Trp^7] SP (1-7) and [Tyr^0, D-Arg^1, D-Pro^<2,4>] SP (1-7).
4)I.t.SP (1-7) and its analogues produced antinociceptive effects as assayd by the capsaicin test.
5)SP (1-7) was also effective on N-methyl-D-aspartate (NMDA)-induced SBL behavioral response, which was reduced by i.t.methylene blue (MB), but not by pretreatment with L-arginine.
6)The effect of MB on the NMDA-induced response was reserved by co-injection of cyclic-GMP.These results suggest that the inhibitory effect of SP (1-7) on the NMDA respose may be involved in increased amount of cyclic-GMP,which is not mediated through nitric oxide system in the mouse spinal cord.