Funding for this research was provided by:
Received: 18 April 2017
Accepted: 10 January 2018
First Online: 29 January 2018
: The animal study was conducted in accordance with the Guide for the Care and Use of Laboratory Animals. The protocol was approved by the Norwegian State Board of Biological Experiments with Living Animals (Project no. 5071).
: Not applicable
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.