Animals

All animal experiments were performed according to the guidelines for Animal Experiment of Kyoto University, the guidelines for the Care and Use of Laboratory Animals of the Institute of Laboratory Animal Resources (ILAR; Washington, DC, USA) and the guideline for the Animals in Research: Reporting in vivo Experiments (ARRIVE). Sixteen week-old female nude rats (F344/NJcl-rnu/rnu) were obtained from CLEA Japan, Inc. (Tokyo, Japan). Nine week-old male mice (C57BL/6NCrSlc) and pregnant female mice (C57BL/6NCrSlc and C57BL/6 6-Tg) were obtained from Shimizu Laboratory Supplies Company Limited (Kyoto, Japan). All animals were housed under diurnal lighting conditions (12 h light/12 h dark) and given standard food and water ad libitum.