animal controlled study rat Animals 139 nonhuman 139 metabolism 123 Rats 119 priority journal 96 animal experiment 92 article 83 animal cell 78 physiology 71 Article 64 drug effect 58 female 57 animal tissue 55 unclassified drug 53 Rats, Sprague-Dawley 52 Sprague Dawley rat 52 Female 51 male 48 Male 44 protein expression 41 drug effects 38 Humans 35 Rats, Wistar 35 Wistar rat 35 animal model 35 human 35 chemistry 32