Animals rat Rats 795 nonhuman 717 article 650 controlled study 557 priority journal 510 animal experiment 465 animal cell 348 Female 336 Male 328 Rats, Sprague-Dawley 322 animal tissue 321 female 276 male 262 animal 260 unclassified drug 200 metabolism 197 Rats, Wistar 196 protein expression 177 animal model 167 Animalia 137 Humans 129 drug effect 121 enzyme activity 120 physiology 118 human 110 in vitro study 93 mouse 92 Mice 91