AVPR1A and autism: Hiroyama et al. (2007) demonstrated the role of V1aR in lipolysis regulation as an antilipolytic agent. V1aR is also associated with autism and induces impaired social behavior, anxiety, and memory. V1aR null mice and microinjections of a V1aR antagonist in rats reduced memory and anxiety, respectively. These results strongly suggest a role for AVP in social behavior (Heinrichs et al., 2009).