Transformation of μ-opioid receptor agonists into biologically potent μ-opioid receptor antagonists
作者:Tingyou Li、Yunden Jinsmaa、Masahiro Nedachi、Anna Miyazaki、Yuko Tsuda、Akihiro Ambo、Yusuke Sasaki、Sharon D. Bryant、Ewa Marczak、Qiang Li
DOI:10.1016/j.bmc.2006.11.019
日期:2007.2.1
N-Allylation (-CH2-CH=CH2) of [Dmt(1)]endomorphins yielded the following: (i) [N-allyl-Dmt(1)]endomorphin-2 (Dmt = 2',6'-dimethyl-L-tyrosine) (12) and [N-allyl-Dmt(1)]endomorphin-1 (15) (K-i mu = 0.45 and 0.26 nM, respectively) became p-antagonists (pA(2) = 8.59 and 8.18, respectively) with weak delta-antagonism (pA(2) = 6.32 and 7.32, respectively); (ii) intracerebroventricularly administered 12 inhibited morphine-induced CNS-mediated antinociception in mice [AD(50) (0.148 ng/mouse) was 16-fold more potent than naloxone], but not spinal antinociception, and (iii) 15 reversed the alcohol-elevated frequency in spontaneous inhibitory post-synaptic currents (IPSC) in hippocampal CA1 pyramidal cells in rat brain slices (P = 0.0055). Similarly, N-allylation of the potent mu-opioidmimetic agonists, 1,6-bis-[H-Dmt-NH]-hexane and 3,6-bis-[Dmt-NH-propyl]-2(1H)-pyrazinone, converted them into p-antagonists (pA(2) = 7.23 and 7.17 for the N-allyl-derivatives 17 and 19, respectively), and exhibited weak delta-antagonism. Thus, N-allylation of Dmt containing opioid peptides or opioidmimetics; continues to provide a facile means to convert selective mu-opioid agonists into potent mu-opioid antagonists. (c) 2006 Elsevier Ltd. All rights reserved.