CNR1 and Anxiety: However, SR-141716A, in contrast to AM-251, affected various functions in CB1-KO mice (including anxiety), suggesting that this antagonist also affects the putative novel receptor (Jarai et al., 1999; Breivogel et al., 2001; Hájos et al., 2001; Haller et al., 2002; Kõfalvi et al., 2003).