HTR5A and Anxiety: Although preliminary studies employing animal models of anxiety have, in general, demonstrated that a reduction in 5-HT neurotransmission plays a role in the effects of novel non-benzodiazepine anxiolytics3, equivocal results for the effects of 5-HT subreceptor ligands have been reported, particularly in studies using the elevated plus-maze paradigm (EPM)4.