low cns exposure

ELN-441958是一种B1受体拮抗剂，能够抑制B1激动剂配体[3H] DAKD 与IMR-90细胞结合(Ki:0.26 nM)，相较于B2受体，它对B1受体的抑制作用具有更高的选择性，且比抑制μ阿片受体选择性高500多倍，比抑制δ阿片受体选择性高2000多倍。

AM-3189 is a potent and selective GPR40 Agonist with minimal CNS penetration, superior pharmacokinetic properties and in vivo efficacy comparable to AMG 837. AM-3189 maintains the in vivo efficacy of AMG 837 while displaying a superior pharmacokinetic profile and minimal CNS exposure. Similar to AMG 837, while highly potent on GPR40, AM-3189 was highly selective over the closely related GPCRs, GPR41 and GPR43. 13kdemonstrated low clearance, moderate volume of distribution, and good oral bioavailability. AM-3189 does not penetrate the rat CNS as indicated by a rat brain to plasma ratio of 0.04 at 3 h after an oral dose of 5 mg kg.