Funding for this research was provided by:
National Institute on Drug Abuse (R21 DA040228, T32 DA017637)
Received: 29 September 2019
Accepted: 19 February 2020
First Online: 5 March 2020
Ethics approval and consent to participate
: All animal housing conditions and experimental procedures were reviewed and pre-authorized by the Institutional Animal Care and Utilization Committee at the University of Colorado Boulder.
: Not applicable.
: The authors declare that they have no competing interests.